https://plumbmatemastery.co.uk/landing.html 2026-06-24 weekly 1.0 https://plumbmatemastery.co.uk/college.html 2026-06-24 monthly 0.9 https://plumbmatemastery.co.uk/subscribe.html 2026-06-03 monthly 0.8 https://plumbmatemastery.co.uk/college-signup.html 2026-06-24 monthly 0.8 https://plumbmatemastery.co.uk/login.html 2026-04-25 yearly 0.7 https://plumbmatemastery.co.uk/how-to-use.html 2026-06-03 monthly 0.8 https://plumbmatemastery.co.uk/glossary.html 2026-06-09 monthly 0.8 https://plumbmatemastery.co.uk/level-3/glossary.html 2026-09-20 monthly 0.7 https://plumbmatemastery.co.uk/about-the-author.html 2026-09-21 yearly 0.6 https://plumbmatemastery.co.uk/blog.html 2026-06-09 weekly 0.9 https://plumbmatemastery.co.uk/trust.html 2026-05-13 monthly 0.7 https://plumbmatemastery.co.uk/leaderboard.html 2026-06-24 weekly 0.6 https://plumbmatemastery.co.uk/certificates.html 2026-05-13 monthly 0.5 https://plumbmatemastery.co.uk/terms.html 2026-04-25 yearly 0.3 https://plumbmatemastery.co.uk/privacy.html 2026-05-13 yearly 0.3 https://plumbmatemastery.co.uk/delete-account.html 2026-08-26 yearly 0.3 https://plumbmatemastery.co.uk/dpa.html 2026-04-24 yearly 0.3 https://plumbmatemastery.co.uk/retention.html 2026-09-25 yearly 0.3 https://plumbmatemastery.co.uk/subscription-agreement.html 2026-04-24 yearly 0.3 https://plumbmatemastery.co.uk/accessibility.html 2026-04-19 yearly 0.3 https://plumbmatemastery.co.uk/blog/how-to-pass-level-2-plumbing.html 2026-06-09 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-safe-isolation.svg The six steps of safe isolation Learn this sequence cold. It is asked every year. https://plumbmatemastery.co.uk/blog/spaced-repetition-plumbing-revision.html 2026-06-09 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-spaced-repetition.svg How to use spaced repetition when revising Test yourself, get it wrong, correct it, and space the repeats out. https://plumbmatemastery.co.uk/blog/level-2-plumbing-exam-mistakes.html 2026-06-09 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-safe-isolation.svg The six steps of safe isolation Out of order is marked wrong, even when every step is there. https://plumbmatemastery.co.uk/blog/plumber-salary-uk-2026.html 2026-06-09 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-career.svg The plumbing qualification and registration pathway Pay follows the qualification and the card, in that order. https://plumbmatemastery.co.uk/blog/level-2-vs-level-3-plumbing.html 2026-06-09 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-career.svg The plumbing qualification and registration pathway One is knowledge, the other is on-site competence. https://plumbmatemastery.co.uk/blog/how-to-become-a-plumber-uk.html 2026-06-09 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-career.svg The plumbing qualification and registration pathway The Diploma and the NVQ are different things. https://plumbmatemastery.co.uk/blog/how-to-get-gas-safe-registered.html 2026-06-09 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-career.svg The plumbing qualification and registration pathway ACS sits on top of a plumbing qualification, not instead of one. https://plumbmatemastery.co.uk/blog/level-2-plumbing-health-safety-revision-guide.html 2026-06-27 monthly 0.8 https://plumbmatemastery.co.uk/images/ppe-task-multiple.png Plumber working on an exposed roof using a power tool while wearing hi-vis, hard hat, ear defenders and a harness https://plumbmatemastery.co.uk/images/hierarchy-of-controls.png Inverted pyramid showing the five-level hierarchy of risk control measures, from elimination at the top to PPE at the bottom https://plumbmatemastery.co.uk/blog/safety-legislation-enforcement-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-legislation-force.svg Which health and safety documents carry legal force Only the top three are law. Guidance shows you how to meet them. https://plumbmatemastery.co.uk/images/harmful-irritant-symbol.jpg The GHS harmful or irritant pictogram Harmful or irritant. The commonest pictogram on a plumbing van, and the one most ignored. https://plumbmatemastery.co.uk/blog/risk-assessment-accidents-first-aid-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/excavation-trench.png Open trench excavation with vertical earth walls, the kind of high-risk work activity that triggers a written risk assessment and method statement https://plumbmatemastery.co.uk/images/hierarchy-of-controls.png Hierarchy of risk control measures shown as an inverted pyramid: elimination, substitution, engineering controls, administrative controls, PPE https://plumbmatemastery.co.uk/images/damaged-hard-hat.png Hard hat with a visible crack across the shell, an example of damaged PPE that should be reported and replaced rather than reused https://plumbmatemastery.co.uk/blog/ppe-safety-signs-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/ppe-task-multiple.png Worker on an exposed roof wearing multiple items of PPE: hi-vis, hard hat, ear defenders and a fall-arrest harness https://plumbmatemastery.co.uk/images/hi-vis-clothing.png Two workers in orange high-visibility jackets and trousers on a railway worksite https://plumbmatemastery.co.uk/images/warning-sign.jpg Yellow triangular warning sign alerting workers to a hazard or risk https://plumbmatemastery.co.uk/images/prohibition-sign.jpg Red circular prohibition sign with a diagonal line, forbidding a specific action https://plumbmatemastery.co.uk/images/mandatory-sign.jpg Blue circular mandatory sign requiring an action to be taken, such as wearing specific PPE https://plumbmatemastery.co.uk/images/information-sign.jpg Green rectangular information / safe condition sign indicating an emergency exit or safe route https://plumbmatemastery.co.uk/images/asbestos-warning.jpg Asbestos warning sign indicating that asbestos-containing materials are present https://plumbmatemastery.co.uk/images/coshh-flammable.png Red diamond CLP pictogram showing a flame, indicating a flammable substance https://plumbmatemastery.co.uk/images/coshh-toxic.png Red diamond CLP pictogram showing a skull and crossbones, indicating a toxic substance https://plumbmatemastery.co.uk/images/coshh-explosive.png Red diamond CLP pictogram showing an exploding bomb, indicating an explosive substance https://plumbmatemastery.co.uk/images/coshh-oxidising.png Red diamond CLP pictogram showing a flame above a circle, indicating an oxidising substance https://plumbmatemastery.co.uk/blog/hazardous-substances-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/coshh-toxic.png Red diamond CLP pictogram showing a skull and crossbones, the toxic hazard symbol used on labelled containers under COSHH https://plumbmatemastery.co.uk/images/corrosive.jpg Yellow warning triangle for a corrosive substance: liquid from two test tubes eating into a bar and a hand https://plumbmatemastery.co.uk/images/asbestos-warning.jpg Asbestos warning sign indicating that the area or material contains asbestos https://plumbmatemastery.co.uk/blog/working-at-height-access-equipment-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/extension-ladder.jpg An extension ladder with two sliding sections, used for higher-level access https://plumbmatemastery.co.uk/images/step-ladder.jpg An A-frame step ladder used for low-level access work https://plumbmatemastery.co.uk/images/roof-ladder.jpg A roof ladder with rollers and a ridge hook used for working safely on pitched roofs https://plumbmatemastery.co.uk/images/ladder-safety-angle.png Ladder leaning against a wall at the correct 75-degree angle with the top extending past the working level https://plumbmatemastery.co.uk/images/cherry-picker-mewp.png Cherry picker boom-lift MEWP with the basket extended on an articulated arm https://plumbmatemastery.co.uk/images/scissor-lift.png Mobile scissor lift with the platform raised on extending criss-cross supports https://plumbmatemastery.co.uk/blog/excavations-confined-spaces-plumbers.html 2026-08-17 monthly 0.7 https://plumbmatemastery.co.uk/images/excavation-trench.png Cross-section of a supported trench showing trench sheets, bracing, spoil set back from the edge, and a secured ladder for access https://plumbmatemastery.co.uk/images/confined-space-entry.png Worker in hi-vis and hard hat climbing down into a manhole, illustrating confined space entry https://plumbmatemastery.co.uk/blog/fire-manual-handling-noise-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/hearing-protection.png Three types of hearing protection: helmet-mounted ear defenders, foam earplugs and over-the-ear headphone-style defenders https://plumbmatemastery.co.uk/images/damaged-extension-cable.png Photograph of an orange extension cable with a damaged plug and frayed sheath, an example of the damage to look for during pre-use checks https://plumbmatemastery.co.uk/blog/gases-hot-work-plumbers.html 2026-08-15 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-gases.svg The four gases a plumber handles and how each behaves Two are heavier than air, one is unstable under pressure, and one is not a fuel at all. https://plumbmatemastery.co.uk/images/coshh-oxidising-unlabelled.jpg The GHS oxidising pictogram Oxidising. Oxygen is not a fuel — it makes everything else burn far more fiercely. https://plumbmatemastery.co.uk/images/flammable.gif A flammable warning sign Flammable. On the cylinder, on the store, and on the risk assessment. https://plumbmatemastery.co.uk/blog/level-2-plumbing-electrical-principles-revision-guide.html 2026-06-27 monthly 0.8 https://plumbmatemastery.co.uk/images/consumer-unit.jpg Domestic consumer unit with main switch and miniature circuit breakers protecting individual final circuits https://plumbmatemastery.co.uk/images/domestic-supply-layout.png Diagram of an incoming domestic electrical supply showing main cable, supplier's fuse, meter, consumer unit and final circuits https://plumbmatemastery.co.uk/blog/ohms-law-power-law-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/VIR.jpeg Ohm's Law formula triangle with V at the top and I multiplied by R at the bottom, used to rearrange V = I × R https://plumbmatemastery.co.uk/images/PIV.jpeg Power Law formula triangle with P at the top and I multiplied by V at the bottom, used to rearrange P = I × V https://plumbmatemastery.co.uk/blog/earthing-bonding-plumbers-level-2.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/domestic-supply-layout.png Diagram of an incoming domestic electrical supply showing the path from supplier's cut-out through the meter to the consumer unit https://plumbmatemastery.co.uk/images/component-x-suppliers-fuse.jpg Supplier's cut-out unit, the sealed enclosure that houses the supplier's main fuse where the public supply enters the property https://plumbmatemastery.co.uk/images/main-earth-bonding.png Main earth and bonding diagram showing the 16mm² main earth conductor and 10mm² main protective bonding conductors to incoming services https://plumbmatemastery.co.uk/images/bathroom-supplementary-bonding.png Bathroom with basin and bath, all metal pipes interconnected by yellow and green supplementary bonding cables https://plumbmatemastery.co.uk/images/supplementary-bonding-clamps.png Close-up of three earth bonding clamps on metal pipes connected by a 4mm² supplementary bonding conductor https://plumbmatemastery.co.uk/images/connector-block.jpg A strip of connector block A connector block is not a temporary continuity bond. The bond is a rated clamped conductor. https://plumbmatemastery.co.uk/images/Temporary-Continuity-Bond.jpg A temporary continuity bond fitted across a cut metal pipe to maintain earth continuity while the pipe is disconnected https://plumbmatemastery.co.uk/images/suppliers-cut-out.png Diagram of a supply intake with the cut-out, meter and bonding The intake: cut-out, meter, main switch — and the bonding that has to be there before you work. https://plumbmatemastery.co.uk/blog/safe-isolation-procedure-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/safe-isolation.webp The three pieces of kit needed for safe isolation: a proving unit, an approved voltage indicator, and a lock-off device fitted with a 'Do not operate — electrician working' warning label https://plumbmatemastery.co.uk/images/voltage-indicator.webp An approved GS38 voltage indicator with two insulated probes and indicator lights for standard voltage levels https://plumbmatemastery.co.uk/images/electrical-lock-off.png A lock-off device with a brass padlock securing a circuit breaker in the off position, preventing it from being switched back on while work is carried out https://plumbmatemastery.co.uk/images/consumer-unit.jpg A domestic consumer unit with a main switch, RCDs and a row of MCBs — the board isolated at the main switch when working inside the unit itself https://plumbmatemastery.co.uk/blog/circuits-and-cables-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/switched-socket-outlet.jpg A twin switched socket outlet A ring final circuit serves sockets from both ends, which is why the cable can be smaller. https://plumbmatemastery.co.uk/images/ring-main.jpg Domestic ring final circuit diagram showing the consumer unit fed from the meter and supplier's main fuse, with main earth bonding to the gas and water supply pipes, and a ring of socket outlets returning to the consumer unit https://plumbmatemastery.co.uk/images/radial-circuit-diagram.png Radial circuit diagram showing a consumer unit feeding a series of sockets in a single line, ending at the last outlet https://plumbmatemastery.co.uk/images/unswitched-fused-spur.jpeg An unswitched fused connection unit An unswitched fused spur at 3 A is the standard supply to heating controls. https://plumbmatemastery.co.uk/images/spur.jpg A spur taken from a ring final circuit, supplying a single additional socket outlet from an existing one https://plumbmatemastery.co.uk/images/double-pole-pullcord.jpeg A double pole pull cord switch Double pole, so both line and neutral are broken — required where there is a bath or shower. https://plumbmatemastery.co.uk/images/Single-gang-socket.jpg A single-gang 13A switched socket outlet of the type used for kitchen appliances https://plumbmatemastery.co.uk/images/twin-and-earth-cable.jpg PVC twin and earth cable, the most common domestic fixed-wiring cable https://plumbmatemastery.co.uk/images/3-core-flex.jpg Heat-resisting 3-core flexible cable used for boiler and immersion connections https://plumbmatemastery.co.uk/images/swa-cable.jpeg A steel wire armoured (SWA) cable cutaway showing the blue outer sheath, the braided steel wire armour beneath it, and three insulated cores (black, grey and red) https://plumbmatemastery.co.uk/images/junction-box.jpg A maintenance free junction box fixed to a joist A maintenance free box may be buried. A screw terminal box must stay accessible. https://plumbmatemastery.co.uk/images/cable-safe-zones.png Diagram showing the safe zones in a room for hidden cables, including the 150mm zones around walls and ceilings and the 50mm depth rule https://plumbmatemastery.co.uk/blog/circuit-protective-devices-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/rewireable-fuse.jpeg Rewireable fuse carriers BS 3036 rewireable carriers. Colour coded by rating, and easily fitted with the wrong wire. https://plumbmatemastery.co.uk/images/High-breaking-capacity-fuse.jpg A high breaking capacity (HBC) cartridge fuse — a heavy-duty cartridge fuse able to interrupt very large fault currents safely HBC fuse https://plumbmatemastery.co.uk/images/b32-circuit-breaker.jpg A type B 32 amp miniature circuit breaker A B32: type B curve, 32 A. The type sets how fast it trips on a fault current. https://plumbmatemastery.co.uk/images/mcb-miniature-circuit-breaker.jpg A miniature circuit breaker (MCB) of the type fitted in a domestic consumer unit, providing overcurrent protection that can be reset rather than replaced Miniature circuit breaker (MCB) https://plumbmatemastery.co.uk/images/bathroom-zones.jpg Bathroom zones diagram showing Zone 0 inside the bath and shower, Zone 1 directly above and adjacent, Zone 2 around the perimeter to 0.6m, and the outside zones beyond Bathroom zones (BS 7671:2018) https://plumbmatemastery.co.uk/images/hcb-fuse.jpeg A high breaking capacity cartridge fuse An HBC cartridge fuse — the one in the supplier cut-out, and in a multimeter lead. https://plumbmatemastery.co.uk/blog/electrical-faults-plumbers-level-2.html 2026-08-15 monthly 0.7 https://plumbmatemastery.co.uk/images/mcb-lock-off.jpeg A lock off device fitted to a circuit breaker in a consumer unit Lock off at the protective device, and keep the key in your own pocket. https://plumbmatemastery.co.uk/images/blog/l2-safe-isolation.svg The six steps of safe isolation Before you touch a fault, isolate and prove dead. https://plumbmatemastery.co.uk/blog/level-2-plumbing-science-revision-guide.html 2026-06-27 monthly 0.8 https://plumbmatemastery.co.uk/images/heat-transfer-methods.png Pan on a hob illustrating the three modes of heat transfer: conduction up the handle, convection in the water and radiation from the hot hob ring https://plumbmatemastery.co.uk/images/static-head-pumping-station.png Pumping station feeding a raised storage tank, with the static head shown as the vertical distance between the water level and the outlet https://plumbmatemastery.co.uk/blog/pressure-and-force-plumbing-level-2.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/beaker.jpg Beaker of liquid illustrating that pressure exerted by a liquid acts in all directions and depends on depth https://plumbmatemastery.co.uk/images/static-head-pumping-station.png Pumping station feeding a raised storage tank with the static head marked between the water level and the outlet https://plumbmatemastery.co.uk/images/pressure_from_cistern.jpg Cold water cistern feeding a 15mm tap with the head height labelled, used to calculate the pressure at the tap inlet https://plumbmatemastery.co.uk/images/compressive-force.jpg Diagram of a block with arrows pushing inward from either side, illustrating compressive force squeezing a body https://plumbmatemastery.co.uk/images/tensile-force.jpg Diagram of a block with arrows pulling outward on either side, illustrating tensile force stretching a body https://plumbmatemastery.co.uk/images/shear-force.jpg Diagram of a block with parallel arrows acting in opposite directions, illustrating shear force sliding two parts of a body across each other https://plumbmatemastery.co.uk/blog/thermal-expansion-plumbing-level-2.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/frozen-pipe-burst.png Copper pipe split open lengthways with ice and water bursting out, caused by water expanding by 9% when it freezes https://plumbmatemastery.co.uk/blog/heat-transfer-plumbing-level-2.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/heat-transfer-methods.png Pan on a hob showing all three heat transfer modes simultaneously: conduction up the handle, convection currents in the water and radiation from the hot hob ring https://plumbmatemastery.co.uk/images/boiler_convection.jpg Diagram of water being heated in a boiler showing convection currents as warm water rises and cooler water sinks https://plumbmatemastery.co.uk/blog/materials-density-heat-capacity-plumbing-level-2.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/capillarity.jpg Capillary action: three glass tubes of different bore standing in water, with the water drawn up above the surrounding level in each and highest in the narrowest, by cohesive and adhesive forces https://plumbmatemastery.co.uk/images/electrolytic-corrosion.png Diagram showing electrolytic corrosion: copper and iron in contact in an electrolyte, with iron releasing electrons and corroding https://plumbmatemastery.co.uk/images/sacrificial-anode.png Diagram of a zinc sacrificial anode connected to an iron component, protecting the iron by corroding preferentially in the electrolyte https://plumbmatemastery.co.uk/blog/combustion-and-fuels-plumbing-level-2.html 2026-08-15 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-fire-fuels.svg The fire triangle and the three fuels Remove any side of the triangle and combustion stops. https://plumbmatemastery.co.uk/blog/level-2-plumbing-processes-revision-guide.html 2026-06-27 monthly 0.8 https://plumbmatemastery.co.uk/images/pipe-bender.jpg A pipe bender (bending machine) used to form bends in copper tube without distorting the bore https://plumbmatemastery.co.uk/images/compression-cut-through.png Cutaway view of a compression fitting showing nut, olive, body and pipe — the canonical mechanical joint https://plumbmatemastery.co.uk/blog/hand-tools-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog-hand-tools-6.jpg A jar of WRAS approved silicone lubricant grease Silicone grease, WRAS approved. The wrong lubricant on a seal is a contamination risk. https://plumbmatemastery.co.uk/images/adjustable-spanner.png An adjustable spanner with a movable jaw set by a worm gear https://plumbmatemastery.co.uk/images/stillson-wrench.png A Stillson pattern pipe wrench A Stillson bites harder as you pull. For steel — it will mark a chromed fitting. https://plumbmatemastery.co.uk/images/blog-heating-commissioning-3.jpg A pair of water pump pliers Water pump pliers — adjustable jaws for holding, not for turning a finished fitting. https://plumbmatemastery.co.uk/images/stillsons.png A pair of Stillson wrenches, the heavy-duty pipe wrench used on threaded steel pipe https://plumbmatemastery.co.uk/images/footprints.jpg Footprint grips, also called pipe-grip pliers, used for gripping iron and steel pipework https://plumbmatemastery.co.uk/images/waterpump-pliers.png Slip-joint waterpump pliers with insulated handles, used for gripping and turning round pipework https://plumbmatemastery.co.uk/images/blog-hand-tools-1.jpg A bolster chisel and lump hammer being used to chase a wall Bolster and lump hammer. Eye protection every time — masonry chips travel. https://plumbmatemastery.co.uk/images/blog-heating-commissioning-4.jpg A pair of insulated cable cutters Insulated cutters, rated and marked. The rating is not a licence to work live. https://plumbmatemastery.co.uk/images/hacksaw.jpg A standard hacksaw with a tensioned blade, the main hand saw for cutting metal pipe https://plumbmatemastery.co.uk/images/junior-hacksaw.png A small-frame junior hacksaw used for cutting smaller pipe, threaded rod and metal trim https://plumbmatemastery.co.uk/images/copper-pipe-cutter.png A rotary wheel copper pipe cutter A wheel cutter gives a square end, then deburr it before the fitting goes on. https://plumbmatemastery.co.uk/images/blog-hand-tools-2.jpg A plastic pipe slice for small diameter copper A pipe slice: rotate it round the tube rather than forcing it, and deburr afterwards. https://plumbmatemastery.co.uk/images/pipe-slice.png A pipe slice — a rotary cutter that scores copper pipe cleanly with a hardened wheel https://plumbmatemastery.co.uk/images/blog-heating-commissioning-5.jpg A pair of side cutters Side cutters for wiring work. Not for cutting anything hardened. https://plumbmatemastery.co.uk/images/blog-hand-tools-3.jpg Plastic pipe shears Shears for plastic pipe. Never a hacksaw — a ragged end will not seal. https://plumbmatemastery.co.uk/images/basin-wrench.jpg A basin wrench with an angled head, used to reach back-nuts on tap tails behind a basin https://plumbmatemastery.co.uk/images/tap-reseating-tool.png A tap reseating tool used to recut the brass seating face inside a tap body where the washer sits https://plumbmatemastery.co.uk/images/radiator-drain-key.png A brass T-bar radiator bleed key: a short barrel with a square socket in its end and a crossbar handle, used to open and close the bleed valve on a radiator https://plumbmatemastery.co.uk/blog/power-tools-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog-power-tools-1.png An SDS rotary hammer drill An SDS hammer drill, for masonry. The one most likely to catch a buried cable. https://plumbmatemastery.co.uk/images/cordless-drill.jpg A cordless drill, the most-used power tool on a plumbing job https://plumbmatemastery.co.uk/images/jigsaw.jpg A jigsaw used by plumbers for cutting holes in floorboards and panels https://plumbmatemastery.co.uk/images/blog-power-tools-4.png A twist drill bit Check the bit as well as the tool. A blunt or chipped bit is how a drill grabs. https://plumbmatemastery.co.uk/images/blog-power-tools-2.png A cordless drill driver Cordless tools sidestep the lead entirely, which is why they took over on site. https://plumbmatemastery.co.uk/images/blog-power-tools-3.jpg A jigsaw A jigsaw throws chips upwards. Eye protection, and both hands on the tool. https://plumbmatemastery.co.uk/images/blog-power-tools-6.jpg A hole saw with its arbor A hole saw and arbor, for a clean hole through a joist or a cylinder. https://plumbmatemastery.co.uk/blog/pipe-materials-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog-pipe-materials-1.jpg A coiled service pipe at a street excavation The service pipe from the main is the first length of the installation you are responsible for. https://plumbmatemastery.co.uk/images/blog-pipe-materials-3.jpg A coil of soft copper microbore tube R220 soft copper, supplied in a coil. Bends by hand, so it suits microbore runs. https://plumbmatemastery.co.uk/images/copper-tee.jpg A copper tee fitting, illustrating the most common metal used for hot and cold water pipework https://plumbmatemastery.co.uk/images/gf-steel-coupling.png Galvanised compression coupling for low carbon steel pipe, used on industrial water and gas installations https://plumbmatemastery.co.uk/images/blog-pipe-materials-6.jpg Bundles of stainless steel tube Stainless: expensive, but it goes where copper would be attacked. https://plumbmatemastery.co.uk/images/stainless-steel-coupling.png Stainless steel threaded coupling with internal threads at both ends, used in food-grade and corrosion-prone installations https://plumbmatemastery.co.uk/images/blog-pipe-materials-4.jpg A coil of blue MDPE service pipe Blue MDPE for an underground service. Kept out of direct sunlight before it goes in. https://plumbmatemastery.co.uk/images/pushfit-coupler.jpg A push-fit coupler typical of plastic plumbing systems, showing the gripper and O-ring inside the body https://plumbmatemastery.co.uk/images/plastic-pipe-slice.png A plastic pipe slice Cut plastic with a slice or shears. A hacksaw leaves swarf that ends up in a valve. https://plumbmatemastery.co.uk/images/blog-pipe-materials-5.jpg A formed bend in copper tube Copper work hardens as it is bent. Anneal it and it goes soft again. https://plumbmatemastery.co.uk/images/blog-pipe-materials-2.jpg An operative pulling a coil of plastic pipe through a joisted floor A coil pulls through a floor in one length — fewer joints where you cannot reach them. https://plumbmatemastery.co.uk/blog/jointing-pipework-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog-jointing-5.jpg Exploded view of a compression joint on copper tube Nut, olive, body. Deburr the tube first or the olive will never seat. https://plumbmatemastery.co.uk/images/blog-jointing-6.jpg A copper tee being soldered with a blowtorch Heat the fitting, not the solder. Capillary action draws it into the joint. https://plumbmatemastery.co.uk/images/end-feed-capillary.jpg An end-feed capillary fitting requiring solder to be added separately at the joint mouth https://plumbmatemastery.co.uk/images/capillary-solder-ring.jpg A solder-ring capillary fitting with the solder pre-loaded inside, used for end-feed-style joints without separate solder https://plumbmatemastery.co.uk/images/solder-ring-fitting.png An integral solder ring capillary fitting Integral solder ring: the solder is already in the fitting. Heat it and it draws round. https://plumbmatemastery.co.uk/images/end-feed-fitting.png An end feed capillary fitting End feed carries no solder. You add it at the mouth and let capillary action pull it in. https://plumbmatemastery.co.uk/images/blowtorch.png Plumber's blowtorch with a red gas cylinder and brass nozzle, the heat source for soldering capillary joints https://plumbmatemastery.co.uk/images/blog-jointing-1.png A plastic push fit coupling Push fit: a grab ring and an O ring. The insert is not optional on soft pipe. https://plumbmatemastery.co.uk/images/pushfit-coupler.jpg A push-fit coupler with the gripping teeth and O-ring visible at the pipe entry https://plumbmatemastery.co.uk/images/blog-jointing-3.png A brass compression coupling Type A: the olive is compressed onto the pipe by the nut. No jointing paste needed. https://plumbmatemastery.co.uk/images/compression-cut-through.png Cutaway view of a non-manipulative (Type A) compression fitting showing the nut, olive, fitting body and pipe https://plumbmatemastery.co.uk/images/manipulative-compression-fitting.png Exploded diagram of a manipulative (Type B) compression fitting where the pipe end is cone-formed before assembly https://plumbmatemastery.co.uk/images/blog-jointing-4.jpg A brass compression coupling cut away to show the olive Cut away, the olive is doing all the work. Over-tightening deforms it and it leaks. https://plumbmatemastery.co.uk/images/blog-jointing-2.jpg A press fit copper coupling Press fit: no flame at all, which is why it has taken over on occupied sites. https://plumbmatemastery.co.uk/images/stainless-steel-coupling.png A stainless steel threaded coupling with internal threads at each end, the type used for threaded LCS pipe joints https://plumbmatemastery.co.uk/images/compression-fitting.png A brass compression coupling Compression: nut, olive and body. No heat, and it comes apart again. https://plumbmatemastery.co.uk/images/equal-tee.jpg An equal tee fitting where all three branches are the same diameter https://plumbmatemastery.co.uk/images/stop-end.jpg A copper stop end used to seal off the end of a pipe run https://plumbmatemastery.co.uk/images/union-connector.jpg A union connector that allows two pipes to be joined and later separated without disturbing the rest of the run https://plumbmatemastery.co.uk/blog/bending-pipe-fabrication-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog-bending-6.png A formed offset in copper tube A bend keeps the bore full. Every fitting you avoid is a joint that cannot leak. https://plumbmatemastery.co.uk/images/hand-pipe-bender.png A hand held lever pipe bender A hand bender for the small sizes, with the former sized to the tube. https://plumbmatemastery.co.uk/images/blog-bending-4.jpg Corrugated flexible pipe Where a bend will not do, corrugated flexible pipe takes the movement instead. https://plumbmatemastery.co.uk/images/blog-bending-1.jpg A stand pipe bender on its tripod A stand bender — for the larger sizes, and for repeat work. https://plumbmatemastery.co.uk/images/pipe-bender.jpg A bench-mounted pipe bender (bending machine) used for forming accurate bends in copper tube https://plumbmatemastery.co.uk/images/scissor-bender.jpg A scissor bending machine with two long handles used for hand-bending small-diameter copper https://plumbmatemastery.co.uk/images/hydraulic-pipe-bender.png Heavy-duty hydraulic pipe bender with a hand-pump lever and pipe formers for bending larger or harder pipe https://plumbmatemastery.co.uk/images/blog-bending-2.png A lever type bender with the former, guide and stop visible Former, back guide and stop. Set the stop wrong and every bend is out. https://plumbmatemastery.co.uk/images/bender-abcd.jpg Labelled diagram of a bending machine showing the former, back-guide, roller and stops https://plumbmatemastery.co.uk/images/blog-bending-5.jpg Internal bending springs of several sizes Springs support the bore from inside. Size to the pipe, and grease before use. https://plumbmatemastery.co.uk/images/internal-spring.png An internal bending spring inserted inside copper pipe to support the wall and prevent collapse during a hand-bend https://plumbmatemastery.co.uk/images/passover-bend.jpg A passover bend used to take a pipe over an obstruction such as another pipe in the run https://plumbmatemastery.co.uk/images/bend-1000-800-90.jpg Bend calculation diagram showing a 15mm copper pipe with a 90-degree bend and labelled centre-to-centre dimensions https://plumbmatemastery.co.uk/images/blog-bending-3.jpg A hydraulic bender set up on a bench A hydraulic bender, for heavier wall pipe than a lever will take. https://plumbmatemastery.co.uk/blog/installation-clipping-fixings-joists-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/joist-notch-drill-zones.jpg Diagram of a floor joist showing safe notch zones near the supports and safe drilling zones along the centre line Floor joist — notch and drill zones https://plumbmatemastery.co.uk/images/blog-installation-5.jpg An expansion anchor set into concrete An expansion anchor in concrete — the fixing for anything heavy on a solid wall. https://plumbmatemastery.co.uk/images/fire-collar.jpg A red intumescent fire collar fitted around a plastic soil pipe where it passes through a fire-rated wall or floor Intumescent fire collar https://plumbmatemastery.co.uk/images/blog-installation-6.jpg Sleeve anchor bolts Sleeve anchors, for a bracket that has to carry real weight. https://plumbmatemastery.co.uk/images/blog-installation-2.png A pozidriv headed screw A pozidriv screw. Driving it with a Phillips bit chews the recess out. https://plumbmatemastery.co.uk/images/countersunk-screw.jpg A countersunk screw with a flat conical head designed to sit flush with or below the surface Countersunk wood screw https://plumbmatemastery.co.uk/images/phillips-screw.jpg A Phillips screw with a tapered four-point cross recess in the head Phillips-head screw https://plumbmatemastery.co.uk/images/pozi-screw.jpg A Pozidriv screw with a four-point cross plus four short additional ribs in the head, designed to resist cam-out Pozidriv screw https://plumbmatemastery.co.uk/images/blog-installation-1.jpg A frame fixing with its plug A frame fixing goes through the item and into the masonry in one. https://plumbmatemastery.co.uk/images/collapsible-anchor.jpg A collapsible anchor (cavity fixing) used to secure pipe brackets to plasterboard or hollow walls Collapsible cavity anchor https://plumbmatemastery.co.uk/images/blog-installation-3.png A long cut masonry nail Nails have no withdrawal resistance worth relying on. Not for anything that carries water. https://plumbmatemastery.co.uk/images/blog-installation-4.jpg A wood screw with a cup washer A cup washer spreads the load and lets the fixing be taken out again cleanly. https://plumbmatemastery.co.uk/blog/plumbing-symbols-drawings-plumbers.html 2026-08-16 monthly 0.7 https://plumbmatemastery.co.uk/images/blog-symbols-2.png Component drawings https://plumbmatemastery.co.uk/images/blog-symbols-1.png Site plan https://plumbmatemastery.co.uk/images/blog-symbols-4.jpg Schematic drawing https://plumbmatemastery.co.uk/images/blog-symbols-5.png Floor plan https://plumbmatemastery.co.uk/images/blog-symbols-3.png Open vented system diagram showing pump, two-port valve, pressure reducing valve, stop valve, single check valve and expansion vessel symbols https://plumbmatemastery.co.uk/images/blog-symbols-6.jpg Water meter https://plumbmatemastery.co.uk/images/symbol-water-meter.jpg The British Standard drawing symbol for a water meter https://plumbmatemastery.co.uk/images/symbol-stop-valve.jpg The British Standard drawing symbol for a stop valve https://plumbmatemastery.co.uk/images/symbol-service-valve.jpg The British Standard drawing symbol for a service or isolation valve https://plumbmatemastery.co.uk/images/symbol-gate-valve.jpg The British Standard drawing symbol for a gate valve https://plumbmatemastery.co.uk/images/symbol-drain-valve.jpg The British Standard drawing symbol for a drain valve or drain-off tap https://plumbmatemastery.co.uk/images/symbol-float-operated-valve.jpg The British Standard drawing symbol for a float operated valve https://plumbmatemastery.co.uk/images/symbol-single-check-valve.jpg The British Standard drawing symbol for a single check valve https://plumbmatemastery.co.uk/images/symbol-double-check-valve.jpg The British Standard drawing symbol for a double check valve https://plumbmatemastery.co.uk/images/symbol-heating-pump.jpg The British Standard drawing symbol for a circulating pump https://plumbmatemastery.co.uk/images/symbol-motorised-valve.jpg The British Standard drawing symbol for a motorised valve https://plumbmatemastery.co.uk/images/symbol-tprv.jpg The British Standard drawing symbol for a temperature and pressure relief valve https://plumbmatemastery.co.uk/images/symbol-expansion-vessel.jpg The British Standard drawing symbol for an expansion vessel https://plumbmatemastery.co.uk/blog/level-2-plumbing-cold-water-revision-guide.html 2026-06-27 monthly 0.8 https://plumbmatemastery.co.uk/images/cistern-abcd.jpg Cold water storage cistern with key components labelled — float valve, overflow, outlet, support board https://plumbmatemastery.co.uk/images/water-mains-hierarchy.jpg Water mains distribution hierarchy from treatment plant through trunk mains and service mains to individual properties https://plumbmatemastery.co.uk/blog/water-sources-supply-to-property.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/water-treatment-cycle.jpg Diagram of the water treatment process from source through abstraction, treatment and distribution to the property https://plumbmatemastery.co.uk/images/water-treatment-abcd.jpg Water treatment process diagram showing the four stages: screening, sedimentation, filtration and disinfection https://plumbmatemastery.co.uk/images/water-mains-hierarchy.jpg Water mains hierarchy from treatment works through trunk mains, secondary mains and communication pipes to each property https://plumbmatemastery.co.uk/images/external-stop-valve.jpg Brass external boundary stop valve with crutch handle, located at the property boundary https://plumbmatemastery.co.uk/images/external-meter.jpg External boundary water meter chamber housing the meter at the property boundary https://plumbmatemastery.co.uk/images/pipe-depths.jpg Section of a water service pipe from the main in the road, under the pavement and garden and up into a house, with its depth of cover marked X and its distance inside the outside wall marked Y https://plumbmatemastery.co.uk/images/pipe-entry-suspended-floor.jpg Insulated cold water service pipe entering the property through a suspended floor, showing the duct and insulation arrangement https://plumbmatemastery.co.uk/blog/direct-vs-indirect-cold-water-systems.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/level-3/img/cw-direct-system.svg Schematic of a direct cold water system where every cold tap is fed directly from the rising main Every cold outlet is fed from the rising main at mains pressure, so every cold tap is drinking water — but there is no reserve if the main is shut off. https://plumbmatemastery.co.uk/level-3/img/cw-indirect-system.svg Schematic of an indirect cold water system with a cold water storage cistern feeding all cold outlets except the kitchen sink The cistern feeds the cold outlets by gravity; only the kitchen sink stays on the rising main, so the drinking water is fluid category 1 straight from the main. https://plumbmatemastery.co.uk/images/service-pipe-abcd.jpg Underground service pipe diagram with components labelled showing the route from the water main to the internal stop valve https://plumbmatemastery.co.uk/blog/cold-water-storage-cisterns.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/cistern-abcd.jpg Cold water storage cistern diagram with key components labelled including the float valve, warning pipe, outlet and overflow https://plumbmatemastery.co.uk/images/part1-fov.jpg BS 1212 Part 1 float-operated valve, the traditional brass piston-type valve https://plumbmatemastery.co.uk/images/part3-fov.jpg BS 1212 Part 3 float-operated valve, the modern diaphragm-type valve used in domestic cold water cisterns https://plumbmatemastery.co.uk/images/cistern-overflow-airgap.jpg Cistern diagram showing the air gap distance between the warning pipe and the highest possible water level https://plumbmatemastery.co.uk/blog/fluid-categories-backflow-prevention.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/backflow-risk-zones.jpg Diagram showing the backflow risk zones around a bath, bidet and WC, illustrating why these locations need specific backflow protection https://plumbmatemastery.co.uk/images/air-gap-photo.jpg Diagram showing the air gap between a tap outlet and the spillover level beneath, the simplest form of backflow prevention https://plumbmatemastery.co.uk/images/basin-tap-airgap.jpg Type AUK2 air gap at a wash hand basin tap, the minimum gap between the tap outlet and the spillover level https://plumbmatemastery.co.uk/images/kitchen-sink-airgap.jpg Type AUK3 air gap above a kitchen sink, the gap between the tap outlet and the sink rim required to prevent backflow https://plumbmatemastery.co.uk/images/single-check-valve-photo.jpg A single check valve, the basic non-return device used for fluid category 2 protection https://plumbmatemastery.co.uk/images/double-check-valve.jpg A double check valve assembly with two non-return discs in series, used for higher-risk fluid category protection https://plumbmatemastery.co.uk/blog/hard-soft-water-frost-protection.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/ph-indicator-strips.png Universal indicator paper strips showing colour reactions across the pH scale, used to test water acidity and hardness https://plumbmatemastery.co.uk/images/limescale-blocked-pipe.png Photograph looking down the bore of a metal pipe almost completely blocked by limescale deposits https://plumbmatemastery.co.uk/images/limescale-plate-heat-exchanger.png Cross-section of a plate heat exchanger showing thick white limescale build-up restricting flow and reducing heat transfer https://plumbmatemastery.co.uk/images/water-softener-diagram.png Cutaway diagram of a base-exchange water softener showing the resin bed, brine tank and bypass arrangement https://plumbmatemastery.co.uk/images/bib-tap-photo.jpg A bib hose union tap, the standard external garden tap that needs draining or insulating to prevent frost damage https://plumbmatemastery.co.uk/blog/cold-water-commissioning-testing-maintenance.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/pressure-test-kit.jpg Pressure test kit with a gauge and braided flexible hose connection used to perform soundness tests on rigid pipework https://plumbmatemastery.co.uk/images/weir-cup-in-use.jpg Weir cup placed under a running kitchen tap to measure flow rate during performance testing https://plumbmatemastery.co.uk/images/commissioning-kit.jpg Commissioning kit including pressure gauge and weir cup, the standard tools for periodic maintenance checks https://plumbmatemastery.co.uk/blog/cold-water-maintenance-fault-finding-plumbers.html 2026-08-15 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-fault-method.svg The order of work when finding a fault Ask, verify, consult, test — then rectify. https://plumbmatemastery.co.uk/blog/taps-float-valves-cold-water-plumbers.html 2026-08-15 monthly 0.7 https://plumbmatemastery.co.uk/images/full-bore-lever-valve.jpg A full bore lever ball valve Full bore, quarter turn, and the handle tells you the position at a glance. https://plumbmatemastery.co.uk/images/blog/l2-isolation-valves.svg Which isolation valve goes where in a cold water system Fitting a gate valve on the main is the classic mistake. https://plumbmatemastery.co.uk/images/bib-tap.jpg A bib tap with a hose union outlet A bib tap with a hose union — which is what raises it to a fluid category 3 risk, or worse. https://plumbmatemastery.co.uk/blog/level-2-plumbing-hot-water-revision-guide.html 2026-06-27 monthly 0.8 https://plumbmatemastery.co.uk/images/cylinder-types.jpg Four hot water cylinder types side by side, the canonical visual for identifying direct, double-feed indirect, single-feed indirect and combination cylinders https://plumbmatemastery.co.uk/images/indirect-double-feed-system.jpg Schematic of an indirect double-feed hot water system showing the cold water storage cistern, F&E cistern, primary circuit and cylinder https://plumbmatemastery.co.uk/blog/hot-water-system-types-classifications.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/instantaneous-electric-photo.jpg An instantaneous electric water heater that produces hot water on demand without storing it https://plumbmatemastery.co.uk/images/unvented-system-isometric-schematic.webp A centralised hot water system where a single boiler and hot water cylinder feed multiple outlets across the whole property through a pipework network https://plumbmatemastery.co.uk/images/under-sink-heater.jpg An under-sink water heater providing localised hot water to a single fitting, the alternative to a centralised cylinder system https://plumbmatemastery.co.uk/images/unvented-system-isometric-schematic.webp An open vented hot water system fed from a cold water storage cistern in the loft, which sets the system pressure by gravity https://plumbmatemastery.co.uk/images/vented-system-isometric-schematic.webp An unvented (sealed) hot water system fed directly from the mains with no loft cistern, relying on an expansion vessel to handle heated-water expansion https://plumbmatemastery.co.uk/images/direct-system-hot.jpg Direct hot water system where the cylinder is heated by an immersion heater or directly by the boiler with no separation between primary and secondary water https://plumbmatemastery.co.uk/images/indirect-double-feed-system.jpg Indirect hot water system schematic with primary and secondary circuits separated by the cylinder coil https://plumbmatemastery.co.uk/blog/heat-sources-hot-water.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/y-plan.png A Y-plan system where a single boiler feeds both the radiators and a hot water cylinder heated indirectly through a coil, with a motorised valve directing flow between heating and hot water A boiler feeding both the radiators and a cylinder indirectly (Y-plan) https://plumbmatemastery.co.uk/images/combination-boiler.jpg A wall-mounted combination boiler, the most common gas-fired heat source in modern UK homes Combination boiler https://plumbmatemastery.co.uk/images/immersion-heater.jpg An immersion heater element fitted into a hot water cylinder, the standard electric heat source for stored hot water Immersion heater element https://plumbmatemastery.co.uk/images/immersion-thermostat-1.jpg An immersion thermostat that switches the immersion heater off when the stored water reaches the set temperature Immersion thermostat https://plumbmatemastery.co.uk/images/biomass-boiler-system.jpg A biomass boiler installation showing the wood pellet hopper, boiler unit and accumulator buffer cylinder Biomass boiler system https://plumbmatemastery.co.uk/images/ground-source.jpg Cutaway of a house with a ground source heat pump: a coiled ground loop buried in a trench in the garden, piped to the heat pump unit and hot water cylinder indoors Ground source heat pump https://plumbmatemastery.co.uk/images/point-of-use-instant-heater.jpg A wall-mounted instantaneous electric water heater with swan-neck spout — a localised heater serving a single outlet without storing hot water Point-of-use instant heater https://plumbmatemastery.co.uk/images/multipoint-heater.jpg A multipoint gas water heater that supplies several outlets without a stored hot water cylinder Multipoint gas water heater https://plumbmatemastery.co.uk/blog/hot-water-cylinder-types.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/four-cylinder-types.jpg Four hot water cylinder types shown side by side for identification — direct, double-feed indirect, single-feed indirect and combination https://plumbmatemastery.co.uk/images/cylinder-with-coil.jpg Double-feed indirect hot water cylinder with internal heating coil, kept entirely separate from the primary water by the coil wall https://plumbmatemastery.co.uk/images/single-feed-cylinder-diagram.jpg Single-feed indirect hot water cylinder diagram showing the air bubble that separates the primary water above from the secondary water below https://plumbmatemastery.co.uk/images/combination-cylinder-diagram.jpg Combination hot water cylinder with the cold water storage cistern integrated on top of the cylinder, used where loft space is limited https://plumbmatemastery.co.uk/images/cylinder-union.jpg A straight cylinder union — the threaded connection used to attach pipework to the tappings on a hot water cylinder https://plumbmatemastery.co.uk/blog/open-vented-hot-water-systems.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/cwsc-and-fe-cistern.jpg Diagram showing the cold water storage cistern (CWSC) feeding the hot water cylinder, with a separate F&E cistern feeding the primary heating circuit https://plumbmatemastery.co.uk/images/pipework-labels-1-4.jpg Open vented hot water system diagram with the four key pipes labelled A to D — the secondary cold feed, secondary open vent, primary cold feed and primary open vent https://plumbmatemastery.co.uk/images/open-vented-pipe-sizes.jpg Open vented hot water and central heating system diagram with the minimum pipe sizes and vent rise dimensions labelled https://plumbmatemastery.co.uk/images/one-pipe-circulation.jpg Hot water cylinder diagram showing one-pipe parasitic circulation, where hot water rises up the connection, cools, and falls back continuously — wasting heat from the stored hot water https://plumbmatemastery.co.uk/blog/unvented-hot-water-systems.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/sealed-heating-dhw-system.jpg Schematic of a sealed (unvented) hot water and central heating system showing the expansion vessel, pressure relief and balanced cold water supply https://plumbmatemastery.co.uk/images/discharge-pipe-d1-d2.webp Unvented discharge pipe arrangement: the D1 metal pipe from the temperature relief valve to the tundish (600 mm maximum), and the D2 pipe from the tundish falling continuously to terminate below a fixed grating over a trapped gulley https://plumbmatemastery.co.uk/images/cylinder-offset-distance.jpg An open vented hot water cylinder fed by gravity from a cold water storage cistern — the traditional arrangement still found in older properties https://plumbmatemastery.co.uk/images/point-of-use-unvented-system.jpg Schematic of a point-of-use unvented hot water storage heater feeding a single outlet, illustrating a smaller-scale unvented installation https://plumbmatemastery.co.uk/blog/hot-water-temperature-control-commissioning.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blending-valve.jpg A thermostatic blending valve that mixes hot and cold water to a safe controlled outlet temperature https://plumbmatemastery.co.uk/images/tmv.jpg A thermostatic mixing valve Fitted as close to the outlet as practicable, with strainers and isolation each side. https://plumbmatemastery.co.uk/images/secondary-circulation-pump.png A secondary circulation pump fitted on a return pipe to keep stored hot water moving continuously to remote outlets https://plumbmatemastery.co.uk/images/pressure-gauge-photo.jpg A pressure gauge on a braided hose, connected to an outlet during performance commissioning to measure the water pressure https://plumbmatemastery.co.uk/images/weir-cup.jpg A weir cup used during performance commissioning to measure the flow rate at hot water outlets https://plumbmatemastery.co.uk/images/airlock-cylinder.jpg Hot water cylinder diagram showing a design fault that traps air at the top of the cylinder and prevents proper hot water delivery https://plumbmatemastery.co.uk/images/reseating-tool.jpg A tap reseating tool used to recut the brass seating face inside a tap body during routine hot water maintenance https://plumbmatemastery.co.uk/blog/hot-water-maintenance-fault-finding-plumbers.html 2026-08-15 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-fault-method.svg The order of work when finding a fault Connect the indicator to the fault before you touch anything. https://plumbmatemastery.co.uk/blog/showers-hot-water-plumbers.html 2026-08-15 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-shower-types.svg The three shower types and what each one requires Unbalanced supplies are behind most of the complaints about mixer showers. https://plumbmatemastery.co.uk/images/single-flow-mixer-pic.jpg A single flow basin mixer tap A single flow mixer blends inside the body, so an unbalanced pair of supplies shows up straight away. https://plumbmatemastery.co.uk/images/tmv.jpg A thermostatic mixing valve A TMV blends down to a safe outlet temperature and fails safe if the cold is lost. https://plumbmatemastery.co.uk/blog/level-2-plumbing-heating-revision-guide.html 2026-06-27 monthly 0.8 https://plumbmatemastery.co.uk/images/y-plan.png Y-plan central heating system diagram showing pump, mid-position valve and pipework arrangement Y-plan system https://plumbmatemastery.co.uk/images/heating-controls.jpg Hand adjusting the dial on a central heating boiler programmer with digital temperature display Heating controls on a domestic boiler https://plumbmatemastery.co.uk/images/3-port-valve.jpg Three-port mid-position motorised valve used in Y-plan central heating systems Three-port mid-position valve https://plumbmatemastery.co.uk/blog/heating-system-types-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog-heating-types-1.png Three dimensional view of a heating circuit serving ground and first floor radiators A wet system: one heat source, water carrying the heat to every emitter. https://plumbmatemastery.co.uk/images/blog-heating-controls-5.png Schematic of a one pipe heating circuit showing radiator positions On a one pipe circuit, each radiator returns into the same main and cools it further. https://plumbmatemastery.co.uk/images/blog-heating-types-3.png Diagram comparing a one pipe system with a two pipe system One pipe returns into the same main. The last radiator always runs coolest. https://plumbmatemastery.co.uk/images/one-pipe-diagram.png One-pipe central heating circuit diagram with radiators connected in series along a single flow loop https://plumbmatemastery.co.uk/images/blog-heating-types-4.png Three dimensional view of a two pipe heating circuit in a house Separate flow and return, so every emitter sees the same flow temperature. https://plumbmatemastery.co.uk/images/two-pipe-diagram.jpg Two-pipe central heating circuit diagram showing separate flow and return pipes serving each radiator https://plumbmatemastery.co.uk/images/blog-heating-types-6.jpg Small bore plastic pipework run under a floor Small bore runs are quick to install and unforgiving of debris. https://plumbmatemastery.co.uk/images/blog-heating-types-2.png Underfloor heating spiral layout showing pipe centres and the wall offset Spiral layout at 200 mm centres, kept 100 mm off the wall face. https://plumbmatemastery.co.uk/images/underfloor-heating-layout.jpg Underfloor heating layout diagram showing manifold, pipe loops in screed and blending valve arrangement https://plumbmatemastery.co.uk/blog/boilers-conventional-system-combi.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog-boilers-1.png Cutaway of a condensing combi boiler showing the primary and secondary heat exchangers Primary heat exchanger for the heating, secondary for the hot water, condensate out at the bottom. https://plumbmatemastery.co.uk/images/blog-boilers-2.jpg A hot water cylinder and cistern in a loft A conventional boiler needs the cylinder and the cistern that go with it. https://plumbmatemastery.co.uk/images/blog-boilers-3.png Schematic of a full heating and hot water system with cylinder, radiators and underfloor A system boiler carries the pump and expansion inside, and still feeds a cylinder. https://plumbmatemastery.co.uk/images/combination-boiler.jpg Schematic of a wall-mounted combination (combi) boiler fed by gas and mains cold water, heating two radiators and sending hot water to two taps, with no cylinder or cistern https://plumbmatemastery.co.uk/images/blog-boilers-6.jpg A magnetic system filter being opened for service Condensing boilers are intolerant of debris, which is why the filter is serviced, not just fitted. https://plumbmatemastery.co.uk/images/blog-boilers-4.jpg A solid fuel range cooker with a back boiler Solid fuel: a minimum stored volume, and a heat leak that cannot be valved off. https://plumbmatemastery.co.uk/images/biomass-boiler-system.jpg Biomass boiler installation showing fuel hopper, boiler unit and accumulator buffer cylinder https://plumbmatemastery.co.uk/images/blog-boilers-5.jpg Boiler pipework and electrical connections on a wall The electrical supply and the pipework both have to be right before it is commissioned. https://plumbmatemastery.co.uk/blog/open-vented-vs-sealed-heating.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog-heating-vented-sealed-3.jpg Schematic of an open vented heating circuit Open to atmosphere through the vent, and fed by the cistern above it. https://plumbmatemastery.co.uk/images/blog-heating-vented-sealed-1.jpg Cutaway house showing an open vented system with its cisterns and cylinder Feed and expansion cistern in the loft, cylinder below, everything fed by gravity. https://plumbmatemastery.co.uk/images/feed-expansion.jpg Feed and expansion cistern in the loft providing make-up water and accommodating expansion in an open-vented heating system https://plumbmatemastery.co.uk/images/close-coupling.jpeg Open-vented heating layout with the neutral point magnified to show the 150mm maximum distance between the cold feed and open vent connections https://plumbmatemastery.co.uk/images/blog-heating-vented-sealed-4.png A sealed system pressure gauge and filling loop beside a cylinder A sealed system: a gauge, a filling loop and an expansion vessel instead of a cistern. https://plumbmatemastery.co.uk/images/sealed-system.jpg Sealed central heating system diagram showing expansion vessel, pressure relief valve and pressure gauge https://plumbmatemastery.co.uk/images/blog-heating-vented-sealed-6.png Diagram showing the neutral point on an open vented system The neutral point: where the cold feed enters, and why the pump goes where it does. https://plumbmatemastery.co.uk/images/blog-heating-vented-sealed-5.jpg Heating primary pipework with a circulating pump and valves The pump, the valves and the feed all in one place — which is where the neutral point argument lives. https://plumbmatemastery.co.uk/images/blog-heating-vented-sealed-2.png A float operated valve being fitted to a cistern The float valve on a feed and expansion cistern is set low — it fills to a few inches only. https://plumbmatemastery.co.uk/images/bypass-valve-photo.jpg An automatic bypass valve The bypass keeps a minimum flow through the boiler when the zone valves close. https://plumbmatemastery.co.uk/blog/heating-system-layouts-s-y-c-plan.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog-heating-layouts-4.png A three port mid-position motorised valve The valve itself. Count the cores and you know which plan you are looking at. https://plumbmatemastery.co.uk/images/blog-heating-layouts-3.png S plan schematic with two two-port zone valves S plan: one valve for heating, one for hot water, both switching the boiler. https://plumbmatemastery.co.uk/images/s-plan.jpg S-plan central heating system diagram with two two-port motorised valves controlling separate heating and hot water circuits https://plumbmatemastery.co.uk/images/s-plan-plus.jpg S-plan plus system diagram showing multiple two-port valves serving zoned heating circuits https://plumbmatemastery.co.uk/images/blog-heating-layouts-1.png Y plan schematic with a three-port mid-position valve Y plan: one valve, three positions, five cores at the valve. https://plumbmatemastery.co.uk/images/y-plan.png Y-plan central heating system diagram with a single three-port mid-position valve controlling heating and hot water https://plumbmatemastery.co.uk/images/blog-heating-layouts-2.png W plan schematic with a three-port diverter valve W plan: a diverter, so it is one or the other — never both at once. https://plumbmatemastery.co.uk/images/blog-heating-layouts-6.jpg Schematic of a semi gravity heating and hot water system C plan: the heating is pumped, the hot water still circulates by gravity. https://plumbmatemastery.co.uk/images/c-plan-system.jpg C-plan semi-gravity heating system diagram with pumped heating circuit and gravity-fed hot water primary https://plumbmatemastery.co.uk/images/blog-heating-layouts-5.png Schematic of a pumped heating only system with a single zone valve A single zone valve, where there is no stored hot water to control. https://plumbmatemastery.co.uk/images/missing-component-diagram.jpg Fully pumped central heating system diagram with one motorised valve missing, used to test recognition of Y-plan and S-plan layouts https://plumbmatemastery.co.uk/blog/heat-emitters-radiator-valves-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/column-radiator-208.png A cast iron column radiator A column radiator: high thermal mass, and a large water content to match. https://plumbmatemastery.co.uk/images/blog-heat-emitters-2.jpg A single panel single convector radiator Single panel, single convector — one fin bank behind one panel. https://plumbmatemastery.co.uk/images/double-panel-convector-208.jpg Double panel double convector radiator showing two heat-emitting panels with finned convectors between https://plumbmatemastery.co.uk/images/column-radiator-208.jpg Traditional column radiator with multiple vertical sections, often used in period-style installations https://plumbmatemastery.co.uk/images/inset-radiator-208.jpg Low surface temperature radiator with protective casing, used in care environments to prevent burns https://plumbmatemastery.co.uk/images/blog-heat-emitters-3.jpg A double panel double convector radiator Double panel, double convector — more output in the same wall length. https://plumbmatemastery.co.uk/images/blog-heat-emitters-6.jpg A brass tee fitting Bottom opposite end is the reference connection. Anything else needs a correction factor. https://plumbmatemastery.co.uk/images/blog-heat-emitters-5.jpg A thermostatic radiator valve head with a remote sensor A TRV with a remote sensor, for where the head itself would sit in still or heated air. https://plumbmatemastery.co.uk/images/trv.jpg Thermostatic radiator valve (TRV) with numbered head used to control individual radiator output https://plumbmatemastery.co.uk/images/lockshield-valve-drain-208.jpg Lockshield radiator valve with plastic cap, used for balancing flow on the return side of a radiator https://plumbmatemastery.co.uk/images/blog-heat-emitters-1.jpg A two port motorised zone valve A two-port zone valve: motor open, spring return. A failed one is usually found by feel. https://plumbmatemastery.co.uk/images/blog-heat-emitters-4.jpg A radiator front panel being opened The panel comes off to clean behind it — convector fins clog, and output drops with them. https://plumbmatemastery.co.uk/blog/heating-system-controls-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog-heating-controls-6.jpg A circulating pump stripped down to show the impeller The impeller is what a seized pump has stopped turning. Most failures are debris. https://plumbmatemastery.co.uk/images/pump-cutaway.jpg Cutaway view of a central heating circulating pump exposing the green impeller driven by the electric motor https://plumbmatemastery.co.uk/images/circulating-pump-photo.jpg A domestic central heating circulating pump with threaded union connections https://plumbmatemastery.co.uk/images/blog-heating-controls-3.jpg The schematic symbol for a two port motorised valve The two-port symbol as it appears on a wiring or system drawing. https://plumbmatemastery.co.uk/images/2-port-valve.jpg Two-port motorised zone valve used to control flow to a single heating or hot water circuit https://plumbmatemastery.co.uk/images/3-port-valve.jpg Three-port mid-position motorised valve as used in a Y-plan central heating system https://plumbmatemastery.co.uk/images/blog-heating-controls-1.png A digital programmer with separate hot water and heating channels Two channels, independently timed. One channel cannot give you interlock on its own. https://plumbmatemastery.co.uk/images/programmer.jpg Domestic heating programmer with separate timing channels for heating and hot water https://plumbmatemastery.co.uk/images/auto-air-vent-photo.png An automatic air vent An automatic air vent — fitted at the high points, where air actually collects. https://plumbmatemastery.co.uk/images/room-thermostat.jpg Wall-mounted room thermostat used to switch the heating circuit on and off based on air temperature https://plumbmatemastery.co.uk/images/cylinder-thermostat.jpg Strap-on cylinder thermostat fitted to a hot water cylinder to control stored water temperature https://plumbmatemastery.co.uk/images/blog-heating-controls-4.png The schematic symbol for a three port motorised valve The three-port symbol. Five cores means mid-position; three means diverter. https://plumbmatemastery.co.uk/images/blog-heating-controls-2.png Diagram of an automatic bypass valve between flow and return Taken off the flow immediately after the pump, back to the return. https://plumbmatemastery.co.uk/images/bypass-valve.jpg Automatic bypass valve fitted between flow and return to relieve pump pressure when zone valves close https://plumbmatemastery.co.uk/images/air-seperator.png An air separator with its connections An air separator takes air out where the water slows and the bubbles can rise. https://plumbmatemastery.co.uk/images/auto-air-vent-photo.jpg Brass automatic air vent with red float-controlled cap, fitted at high points to release trapped air automatically https://plumbmatemastery.co.uk/images/air-separator.jpg Central heating air separator with four ports used to remove entrained air from the system https://plumbmatemastery.co.uk/blog/heating-commissioning-testing-fault-finding.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog-heating-commissioning-1.png A Benchmark commissioning checklist alongside a boiler The Benchmark checklist is what supports the warranty. It is filled in on the day. https://plumbmatemastery.co.uk/images/blog-heating-commissioning-6.jpg A hydraulic pressure test pump with gauge and hose A hydraulic test pump. Read the gauge over the held period, not just at the start. https://plumbmatemastery.co.uk/images/hydraulic-test-pump-208.jpg Hand-operated hydraulic test pump used to pressurise heating pipework for a soundness test https://plumbmatemastery.co.uk/images/blog-heating-commissioning-2.jpg A power flushing machine with its connection fittings Power flushing gear. BS 7593 — clean the system before the boiler ever runs. https://plumbmatemastery.co.uk/images/bleed-key-208.jpg Radiator bleed key used to release trapped air from radiators after filling and venting the system https://plumbmatemastery.co.uk/images/drainoff-positions.jpg Drain-off valve positions on a central heating system showing where to drain different sections of the circuit https://plumbmatemastery.co.uk/blog/central-heating-pipework-materials-insulation-clipping.html 2026-08-15 monthly 0.7 https://plumbmatemastery.co.uk/images/blog-heating-pipework-1.png PVC foam pipe insulation https://plumbmatemastery.co.uk/images/blog-heating-pipework-2.png Barrier tube for a heating circuit The barrier layer keeps oxygen out. Without it the system corrodes from the inside. https://plumbmatemastery.co.uk/images/blog-heating-pipework-4.png Expanded nitrile pipe insulation https://plumbmatemastery.co.uk/images/blog-heating-pipework-5.png Pipe clips supporting a heating run Clip to the table. Unclipped pipe expands, moves and eventually knocks. https://plumbmatemastery.co.uk/images/blog-heating-pipework-3.png Pipework marked with tape and open ends capped during first fix https://plumbmatemastery.co.uk/images/blog-heating-pipework-6.jpg Pipework run through drilled joists Through the neutral axis, in the permitted zone, and never a notch and a hole together. https://plumbmatemastery.co.uk/blog/level-2-plumbing-drainage-revision-guide.html 2026-06-27 monthly 0.8 https://plumbmatemastery.co.uk/images/blog/l2-stack-systems.svg The four above-ground drainage stack systems Know these four and most of the unit follows. https://plumbmatemastery.co.uk/blog/traps-and-trap-seal-loss.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-trap-seal-loss.svg The mechanisms by which a trap loses its seal Nine mechanisms, and each one leaves a different pattern behind. https://plumbmatemastery.co.uk/images/self-siphonage.jpg Diagram of self-siphonage emptying a trap Self-siphonage: the discharge fills the branch and pulls the seal out behind it. https://plumbmatemastery.co.uk/images/blog/l2-trap-seals.svg Trap seal depths by appliance The depth fitted varies. The 25 mm that must remain does not. https://plumbmatemastery.co.uk/blog/drainage-stack-systems-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-stack-systems.svg The four above-ground drainage stack systems Branch lengths and building height decide which one you use. https://plumbmatemastery.co.uk/images/aav-component-2-209.png An air admittance valve An AAV lets air in and nothing out. It never replaces the stack terminal at the top. https://plumbmatemastery.co.uk/blog/drainage-pipe-materials-jointing-fittings.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/110mm-drain-connector-209.png A 110 mm drainage connector 110 mm is the standard soil size. The ring seal takes the movement a solvent joint cannot. https://plumbmatemastery.co.uk/images/blog/l2-drainage-joints.svg Which jointing method suits which drainage material Polypropylene cannot be solvent welded. https://plumbmatemastery.co.uk/blog/drainage-testing-maintenance.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-drain-tests.svg Soundness testing compared with performance testing One proves the pipe; the other proves the seals. https://plumbmatemastery.co.uk/images/drain-plug-component-209.png An expanding drain test plug An expanding test plug seals the end while the system is put under air pressure. https://plumbmatemastery.co.uk/images/blog-hand-tools-4.jpg An operative jetting a drain outside a property Jetting where rodding will not reach. Full PPE — what comes back is foul. https://plumbmatemastery.co.uk/blog/rainwater-guttering-systems.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-guttering.svg Guttering spacing, fall and outlet figures Too few brackets and it sags, holds water and overflows. https://plumbmatemastery.co.uk/blog/underground-drainage-systems-gullies.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-drainage-joints.svg Which jointing method suits which drainage material Material and joint go together underground as well as above. https://plumbmatemastery.co.uk/images/auger-tool-209.png A hand drain auger An auger reaches round a bend a rod will not. Least invasive first. https://plumbmatemastery.co.uk/blog/level-2-plumbing-communications-revision-guide.html 2026-06-27 monthly 0.8 https://plumbmatemastery.co.uk/images/blog/l2-verbal-written.svg Verbal and written communication compared Most of this unit comes back to choosing the right method. https://plumbmatemastery.co.uk/blog/customer-communication-service-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-quote-estimate.svg The difference between a quotation and an estimate A quotation is fixed. An estimate can move. https://plumbmatemastery.co.uk/blog/effective-communication-conflict-resolution-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-verbal-written.svg Verbal and written communication compared Formal or informal is a separate choice from verbal or written. https://plumbmatemastery.co.uk/blog/workplace-documents-drawings-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/pump-symbol.jpg British Standard plumbing drawing symbol for a circulating pump https://plumbmatemastery.co.uk/images/gate-valve-symbol.png British Standard plumbing drawing symbol for a gate valve https://plumbmatemastery.co.uk/images/stop-valve-symbol.jpg British Standard plumbing drawing symbol for a stop valve https://plumbmatemastery.co.uk/images/drain-valve-symbol.jpg British Standard plumbing drawing symbol for a drain-off valve https://plumbmatemastery.co.uk/images/single-check-valve-symbol.jpg British Standard plumbing drawing symbol for a single check valve https://plumbmatemastery.co.uk/blog/construction-roles-site-structure-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-site-structure.svg Who reports to whom on a construction site Instructions come down the chain; requests go up it. https://plumbmatemastery.co.uk/blog/employment-equality-contracts-plumbers.html 2026-06-27 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-employment.svg What employment law requires in a contract It has to be in writing, and it has to say these things. https://plumbmatemastery.co.uk/level-1-blog.html 2026-09-01 weekly 0.8 https://plumbmatemastery.co.uk/level-3-blog.html 2026-09-06 weekly 0.8 https://plumbmatemastery.co.uk/level-1-glossary.html 2026-09-01 weekly 0.7 https://plumbmatemastery.co.uk/short-courses-blog.html 2026-09-01 weekly 0.8 https://plumbmatemastery.co.uk/short-courses-glossary.html 2026-09-01 weekly 0.7 https://plumbmatemastery.co.uk/gas-blog.html 2026-08-16 weekly 0.8 https://plumbmatemastery.co.uk/blog/gas-analyser-care-calibration.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-analyser-figures.svg How to care for and calibrate a flue gas analyser An analyser you cannot prove is calibrated is a reading you cannot defend. https://plumbmatemastery.co.uk/images/blog/gas-analyser-use.svg How to use a flue gas analyser correctly The routine before the test decides whether the reading means anything. https://plumbmatemastery.co.uk/blog/gas-benchmark-commissioning.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-commissioning-sequence.svg The order of commissioning a gas boiler Clean, set, prove, record — in that order. https://plumbmatemastery.co.uk/blog/gas-boiler-interlock-controls.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-interlock.svg What delivers boiler interlock and why TRVs alone do not Interlock is about switching the boiler off, not throttling the water. https://plumbmatemastery.co.uk/blog/gas-boiler-types.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-boiler-types.svg The three boiler types and what each one needs The difference is where the hot water comes from and what the system needs around it. https://plumbmatemastery.co.uk/images/blog/comp-room-sealed-boiler.svg A cutaway of a room-sealed condensing boiler Concentric terminal, sealed case, fan, burner, heat exchanger and the trap underneath it. https://plumbmatemastery.co.uk/blog/gas-ccn1-core-gas-safety-guide.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/comp-gas-intake.svg A labelled gas intake showing the emergency control valve, meter and test point The ECV, the meter and the test point — the three things every job starts at. https://plumbmatemastery.co.uk/images/blog/gas-tightness-test.svg The steps of a gas tightness test The test proves the installation is sound; purging makes it usable. https://plumbmatemastery.co.uk/blog/gas-cenwat-boilers-water-heaters-guide.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-interlock.svg What delivers boiler interlock and why TRVs alone do not A TRV throttles water. Only a control that switches the boiler gives interlock. https://plumbmatemastery.co.uk/blog/gas-ckr1-cookers-guide.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-cooker-ventilation.svg Cooker ventilation requirements by room volume 100, 50, nil — and the door-to-outside exception. https://plumbmatemastery.co.uk/blog/gas-co-co2-ratio.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-co-co2.svg The CO/CO2 ratio action level and the figures around it A ratio is independent of how much air has diluted the sample. A raw CO figure is not. https://plumbmatemastery.co.uk/blog/gas-condensate-handling.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-condensate.svg How to run and terminate a condensate pipe Internal if you possibly can — an internal termination cannot freeze. https://plumbmatemastery.co.uk/images/blog/comp-condensate-trap.svg A condensate trap and the run from the boiler to the drain The seal in the trap, 19 mm inside, 30 mm and insulated outside, and an air break at the end. https://plumbmatemastery.co.uk/blog/gas-cooker-clearances-combustibles.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-cooker-clearances.svg Cooker clearances to combustible surfaces The manufacturer instructions always take precedence over any general figure. https://plumbmatemastery.co.uk/blog/gas-cooker-stability-anti-tip.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/comp-cooker-stability.svg A cooker tipping about its front feet, and the stability device that resists it The load on an open door, the pivot at the front feet, and the chain or bracket that holds it. https://plumbmatemastery.co.uk/images/blog/gas-cooker-clearances.svg Cooker clearances and the stability device The chain and the clearances are checked together at commissioning. https://plumbmatemastery.co.uk/blog/gas-cooker-ventilation-room-volume.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-cooker-ventilation.svg Cooker ventilation requirements by room volume Lock this table in — it is asked almost every time. https://plumbmatemastery.co.uk/blog/gas-cpa1-combustion-analysis-guide.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-co-co2.svg The CO/CO2 ratio action level and the figures around it 0.0040 is the number the whole assessment turns on. https://plumbmatemastery.co.uk/blog/gas-dfe-ilfe-fires.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/comp-dfe-ilfe-opening.svg A DFE and an ILFE fire in a builder’s opening, in section Where the closure plate and the catchment space sit, and what is open to the chimney. https://plumbmatemastery.co.uk/images/blog/gas-flue-testing.svg The order of flue flow and spillage testing Both types are commissioned with a flue flow and a spillage test. https://plumbmatemastery.co.uk/blog/gas-failed-combustion-result.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-fail-procedure.svg What to do when a combustion test fails Four steps, in order. A fail is a procedure, not a panic. https://plumbmatemastery.co.uk/blog/gas-flame-supervision-devices.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/comp-fsd-thermocouple.svg A thermocouple flame supervision device, with the flame lit and with the flame out The flame makes the voltage that holds the valve open. Nothing else is holding it. https://plumbmatemastery.co.uk/images/blog/gas-fsd-types.svg The two types of flame supervision device compared Two mechanisms, one job: shut the gas off if the flame is not there. https://plumbmatemastery.co.uk/blog/gas-flue-flow-spillage-testing.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-flue-testing.svg The order of flue flow and spillage testing Flow proves the flue works. Spillage proves it works with the room as it really is. https://plumbmatemastery.co.uk/blog/gas-flueless-heaters-ods.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/comp-ods-pilot.svg An oxygen depletion pilot with the flame seated on the thermocouple and lifted off it The pilot is built to become unstable first, so the thermocouple cools before the room becomes dangerous. https://plumbmatemastery.co.uk/images/blog/gas-ventilation.svg Ventilation requirements for gas appliances With no flue, the room itself is doing the work — so its volume matters. https://plumbmatemastery.co.uk/blog/gas-flues-types-testing.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/comp-flue-types.svg Open flued and room sealed appliances compared Type B takes its air from the room. Type C never does. https://plumbmatemastery.co.uk/images/blog/gas-appliance-types.svg The three appliance and flue types Room sealed is safest, because room air is never part of combustion. https://plumbmatemastery.co.uk/blog/gas-hearths-clearances-closure-plates.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-cooker-clearances.svg Clearances to combustible surfaces The manufacturer instructions take precedence over any general figure. https://plumbmatemastery.co.uk/blog/gas-htr1-space-heaters-guide.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-flue-testing.svg The order of flue flow and spillage testing Always worst case: doors and windows shut, extract fans running. https://plumbmatemastery.co.uk/blog/gas-pipe-sizing-installation.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-pipe-sizing.svg The steps of sizing a gas pipe against a 1 mbar pressure drop Everything in the calculation exists to keep the drop under 1 mbar. https://plumbmatemastery.co.uk/blog/gas-rates-burner-pressure.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-rates-pressures.svg The three gas pressures and the gas rate Burner pressure alone is never enough — rate it and you know what it is really burning. https://plumbmatemastery.co.uk/blog/gas-tightness-testing-purging.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/comp-u-gauge-test.svg A U-gauge connected to the meter test point for a tightness test What the gauge is actually connected to, and what the head between its two legs is telling you. https://plumbmatemastery.co.uk/images/blog/gas-tightness-test.svg The steps of a gas tightness test Stabilise, pressurise, hold, read — then purge. https://plumbmatemastery.co.uk/blog/gas-unsafe-situations-giusp.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-giusp.svg Immediately Dangerous and At Risk compared under the GIUSP Make safe first, then classify, then warn and record. https://plumbmatemastery.co.uk/blog/gas-using-flue-gas-analyser.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-analyser-use.svg How to use a flue gas analyser correctly Good readings start with good routine. https://plumbmatemastery.co.uk/images/blog/comp-analyser-sample-path.svg The path a flue gas sample takes through an analyser Probe, water trap, filter, pump, cells — and the two stages that quietly ruin a reading. https://plumbmatemastery.co.uk/blog/gas-ventilation-requirements.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/gas-ventilation.svg Ventilation requirements for gas appliances The vent is sized on the excess over 7 kW, not on the whole input. https://plumbmatemastery.co.uk/images/blog/comp-air-vent.svg An air vent in section, showing gross area against free area Gross area is the hole. Free area is the gaps — and free area is what the rule is written in. https://plumbmatemastery.co.uk/blog/gas-water-heaters.html 2026-06-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/comp-unvented-devices.svg The safety devices on an unvented water heater, in the order they act Thermostat, energy cut-out, then temperature and pressure relief — each one only exists because the last failed. https://plumbmatemastery.co.uk/images/blog/gas-unvented-protection.svg The layers of thermal protection on an unvented cylinder The control thermostat is functional. Only the other two are safety devices. https://plumbmatemastery.co.uk/courses/courses-gas-reassessment.html 2026-07-04 monthly 0.9 https://plumbmatemastery.co.uk/courses/courses-unvented.html 2026-07-04 monthly 0.9 https://plumbmatemastery.co.uk/courses/courses-water-regs.html 2026-07-04 monthly 0.6 https://plumbmatemastery.co.uk/courses/courses-underfloor-heating.html 2026-08-30 monthly 0.6 https://plumbmatemastery.co.uk/courses/courses-low-temp-heating.html 2026-08-30 monthly 0.6 https://plumbmatemastery.co.uk/courses/courses-heat-pumps.html 2026-07-04 monthly 0.6 https://plumbmatemastery.co.uk/courses/courses-solar-thermal.html 2026-07-04 monthly 0.6 https://plumbmatemastery.co.uk/blog/heat-loss-fabric-and-ventilation.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-heat-loss.svg The fabric and ventilation heat loss calculations Two routes out of the building, added together. https://plumbmatemastery.co.uk/blog/heat-pump-commissioning-handover.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-hp-commissioning.svg The order of commissioning a heat pump Water quality decides how long the machine lasts. https://plumbmatemastery.co.uk/blog/heat-pump-fault-finding-servicing.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-hp-faults.svg The method for finding a fault on a heat pump A fault code names a symptom, not a part. https://plumbmatemastery.co.uk/blog/heat-pump-installation-practice-guide.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-ground-arrays.svg The four ground collector arrangements Land, not preference, decides which one you can have. https://plumbmatemastery.co.uk/blog/heat-pump-regulations-mcs-building-regs.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-hp-commissioning.svg The order of commissioning a heat pump MCS sets how the work is done and recorded. https://plumbmatemastery.co.uk/blog/heat-pump-survey-sizing-ground-arrays.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-ground-arrays.svg The four ground collector arrangements Depths and spacings are the ones that get asked. https://plumbmatemastery.co.uk/blog/heat-pump-system-design-flow-emitters-cylinders.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-low-temp.svg The key figures for low temperature heating design Low flow temperature means bigger emitters. There is no way round it. https://plumbmatemastery.co.uk/blog/heat-pumps-how-they-work-principles.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-refrigerant-cycle.svg The four stages of the refrigerant cycle A heat pump moves heat — it does not make it. https://plumbmatemastery.co.uk/images/blog/comp-ashp-unit.svg A labelled air source heat pump outdoor unit The unit itself: fan, evaporator coil, and the flow and return to the house. https://plumbmatemastery.co.uk/images/blog/l2-cop-scop.svg COP compared with SCOP and SPF COP sells the product. SPF is what the customer actually pays to run. https://plumbmatemastery.co.uk/blog/hot-water-for-low-temperature-systems.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-low-temp.svg The key figures for low temperature heating design Hot water sets a floor the heating circuit does not. https://plumbmatemastery.co.uk/blog/low-temperature-heating-explained.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-low-temp.svg The key figures for low temperature heating design The return temperature is the one that decides whether a boiler condenses. https://plumbmatemastery.co.uk/blog/low-temperature-system-design-commissioning.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-hp-commissioning.svg The order of commissioning a low temperature system Cleanliness matters more the lower the flow temperature goes. https://plumbmatemastery.co.uk/blog/pipe-sizing-pumps-low-temperature-heating.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-low-temp.svg The key figures for low temperature heating design A smaller ΔT means a bigger flow rate for the same output. https://plumbmatemastery.co.uk/blog/room-by-room-heat-loss-calculation.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-heat-loss-method.svg The steps of a room by room heat loss calculation Fabric and ventilation, added together, one room at a time. https://plumbmatemastery.co.uk/blog/sizing-radiators-at-low-temperature.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-radiator-sizing.svg How to size a radiator at a low flow temperature Divide to buy, multiply to check. https://plumbmatemastery.co.uk/blog/solar-thermal-commissioning-handover.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-solar-commissioning.svg The order of commissioning a solar thermal system The labels you leave are what protect the system at its next service. https://plumbmatemastery.co.uk/blog/solar-thermal-fault-finding-servicing.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-stagnation.svg Stagnation temperatures and how to judge a spent heat transfer fluid The fluid is a consumable. Judging it by pH and smell is part of a service. https://plumbmatemastery.co.uk/blog/solar-thermal-how-it-works-collectors.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-solar-resource.svg The solar resource available in the UK and what affects it About 60 per cent of annual hot water, and nothing at all to space heating. https://plumbmatemastery.co.uk/images/blog/comp-flat-plate.svg A labelled flat plate solar collector A flat plate collector, and the parts a data sheet refers to. https://plumbmatemastery.co.uk/blog/solar-thermal-installation-practice.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-solar-install.svg The steps of installing a solar thermal collector Fix into the structure, weather the penetration, and allow for the movement. https://plumbmatemastery.co.uk/blog/solar-thermal-regulations-mcs-planning.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-solar-compliance.svg What governs a solar thermal installation Part A is the one people forget, and it is the one that keeps it on the roof. https://plumbmatemastery.co.uk/blog/solar-thermal-survey-sizing-wind-loading.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-solar-survey.svg The steps of surveying a roof for solar thermal Wind uplift, not weight, is what takes an array off a roof. https://plumbmatemastery.co.uk/blog/solar-thermal-system-types-primary-circuit.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-solar-system-types.svg Fully filled pressurised and drain-back systems compared Drain-back solves stagnation and freezing by removing the fluid from the collector. https://plumbmatemastery.co.uk/images/blog/comp-solar-pump-station.svg A labelled solar pump station Pump, gauges, safety valve, flow meter and the vessel that takes the stagnation volume. https://plumbmatemastery.co.uk/blog/underfloor-heating-commissioning-fault-finding.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-ufh-commissioning.svg The order of commissioning underfloor heating Never heat a screed before it has cured. https://plumbmatemastery.co.uk/blog/underfloor-heating-design-calculations.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-ufh-design.svg The steps of designing an underfloor heating circuit If the surface limit will not give the output, the answer is insulation. https://plumbmatemastery.co.uk/blog/underfloor-heating-floor-constructions.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-ufh-constructions.svg Screed and timber underfloor heating constructions compared Thermal mass is the real difference between them. https://plumbmatemastery.co.uk/images/blog-heating-types-5.png Typical underfloor heating floor constructions: solid, suspended and floating Solid, suspended and floating — three constructions, three very different responses. https://plumbmatemastery.co.uk/blog/underfloor-heating-floor-coverings.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-ufh-limits.svg Underfloor heating surface temperature and output limits The covering and the surface limit together cap the output. https://plumbmatemastery.co.uk/blog/underfloor-heating-how-it-works.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-ufh-limits.svg Underfloor heating surface temperature and output limits The floor is the emitter, and its surface temperature is capped. https://plumbmatemastery.co.uk/blog/underfloor-heating-installation-practice.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-ufh-sequence.svg The order of installing underfloor heating The pressure test stays on through the pour. https://plumbmatemastery.co.uk/blog/underfloor-heating-manifolds-controls.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-ufh-constructions.svg Screed and timber underfloor heating constructions compared Follow the water and the manifold makes sense. https://plumbmatemastery.co.uk/blog/unvented-commissioning-fault-finding.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-discharge-reading.svg How to read a discharge to tell a pressure fault from a temperature fault Cold means pressure, hot means temperature. https://plumbmatemastery.co.uk/images/unvented-pressure-relief.jpg An expansion relief valve The expansion relief valve on the cold side. A cold discharge points here first. https://plumbmatemastery.co.uk/blog/unvented-cylinders-expansion.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/combination-cylinder-unit.png A combination cylinder unit with the cistern built in A combination unit: cylinder and cistern in one, for where there is no loft to use. https://plumbmatemastery.co.uk/images/blog/l2-inlet-set.svg The order of components in an unvented inlet control set Expansion is dealt with at the inlet, or inside the cylinder. https://plumbmatemastery.co.uk/blog/unvented-discharge-pipework-tundish.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-discharge-chain.svg The D1, tundish and D2 discharge figures D1 is short and steep. D2 is long and shallow. https://plumbmatemastery.co.uk/blog/unvented-functional-controls-inlet-set.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-inlet-set.svg The order of components in an unvented inlet control set Isolate, strain, reduce, prevent return, relieve. https://plumbmatemastery.co.uk/images/pressure-reducing-valve.jpg A pressure reducing valve with a gauge A pressure reducing valve sets the working pressure the rest of the set is designed around. https://plumbmatemastery.co.uk/blog/unvented-hot-water-principles-hazard.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-unvented-stack.svg The three layers of thermal protection on an unvented cylinder The whole safety stack exists because of what happens to water above 100 °C. https://plumbmatemastery.co.uk/blog/unvented-regulations-siting-certification.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-unvented-stack.svg The three layers of thermal protection on an unvented cylinder The law is what requires these devices to be there. https://plumbmatemastery.co.uk/blog/unvented-safety-controls-temperature.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/unvented-temperature-pressure-relief.jpg A temperature and pressure relief valve with its probe The T&P valve, with the probe in the stored water. Factory fitted, and never relocated. https://plumbmatemastery.co.uk/images/blog/l2-unvented-stack.svg The three layers of thermal protection on an unvented cylinder The control thermostat is functional. Only the other two are safety devices. https://plumbmatemastery.co.uk/blog/water-regs-backflow-prevention-applications.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-air-gaps.svg Air gaps and tap gaps and what each protects against AUK2 is set by the tap. AUK3 is set by the bore. https://plumbmatemastery.co.uk/blog/water-regs-backflow-prevention-devices.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-air-gaps.svg Air gaps and tap gaps and what each protects against No mechanical device reaches fluid category 5 — which is why the gaps exist. https://plumbmatemastery.co.uk/blog/water-regs-cold-water-cisterns.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-pipework-protection.svg Protecting pipework, and the depths and cover required A cistern is protected the same way a buried pipe is: from what can get into it. https://plumbmatemastery.co.uk/blog/water-regs-cross-connection-unwholesome-water.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-fluid-categories.svg The five fluid categories A cross connection is an offence in itself. https://plumbmatemastery.co.uk/blog/water-regs-fluid-categories.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-fluid-categories.svg The five fluid categories The category follows the use, not the appliance. https://plumbmatemastery.co.uk/blog/water-regs-hot-water-safety-devices.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-unvented-stack.svg The three layers of thermal protection on an unvented cylinder Two independent safety devices, in addition to the control thermostat. https://plumbmatemastery.co.uk/blog/water-regs-installation-protection-pipework.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/pipe-depths-y.jpg Diagram showing the required depth of cover on a buried service pipe Not less than 750 mm, not more than 1350 mm. Outside that, it is notifiable. https://plumbmatemastery.co.uk/images/blog/l2-pipework-protection.svg Protecting pipework, and the depths and cover required Too shallow and it freezes; too deep and it is notifiable. https://plumbmatemastery.co.uk/images/supply-pipe.jpg Diagram of a service pipe entering a building Where the service pipe comes in: ducted, sleeved and able to be replaced. https://plumbmatemastery.co.uk/blog/water-regs-law-scope-notification.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-pressure-test-sequence.svg The sequence required before a system is first used Notification is one duty; the pre-use sequence is another. https://plumbmatemastery.co.uk/blog/water-regs-materials-fittings-approvals.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-reg4-tests.svg Regulation 4 suitability and approval compared A fitting can be approved and still be unsuitable for this installation. https://plumbmatemastery.co.uk/blog/water-regs-pressure-testing-flushing-disinfection.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-pressure-test-sequence.svg The sequence required before a system is first used Tested, flushed, then disinfected — in that order. https://plumbmatemastery.co.uk/blog/water-regs-sanitary-appliances-water-efficiency.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-water-efficiency.svg Water efficiency and flush volume figures The figures that get asked, in one place. https://plumbmatemastery.co.uk/blog/water-regs-system-design-valves.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-valves.svg Which valve goes where in a water system Dead legs are designed out, not accepted. https://plumbmatemastery.co.uk/blog/water-regs-wcs-urinals-flushing.html 2026-08-30 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l2-water-efficiency.svg Water efficiency and flush volume figures 6 litres maximum since 1 January 2001. https://plumbmatemastery.co.uk/blog/level-1-construction-industry-plumbers.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-1-construction-industry-plumbers-figures.svg Key figures for the construction industry for level 1 plumbers The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-101-business-types.svg The four ways a construction business can be owned The dividing line is whether you or the company carries the debts. https://plumbmatemastery.co.uk/blog/level-1-safe-working-practices.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/information-sign.gif A green fire exit safe condition sign Safe condition. Green — this is the way out, or the thing that helps you. https://plumbmatemastery.co.uk/images/blog/l1-1-safe-working-practices-figures.svg Key figures for safe working for level 1 plumbers The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-102-manual-handling.svg The four steps of safe manual handling, with technique last Avoid, assess, reduce — and only then technique. https://plumbmatemastery.co.uk/blog/level-1-environmental-sustainability-plumbing.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-1-environmental-sustainability-plumbing-figures.svg Key figures for environment and sustainability for level 1 plumbers The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-103-waste-classes.svg The three classes of waste and what goes in each The class decides the cost, and the fluorescent tube is the one people get wrong. https://plumbmatemastery.co.uk/blog/level-1-site-preparation-tools-fixings.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-1-site-preparation-tools-fixings-figures.svg Key figures for site preparation for level 1 plumbers The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-101-fix-order.svg The order of first fix and second fix on a building site Your work is sandwiched between other trades, in a fixed order. https://plumbmatemastery.co.uk/blog/level-1-above-ground-drainage-guttering-waste.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-1-above-ground-drainage-guttering-waste-figures.svg Key figures for above ground drainage for level 1 The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-103-waste-hierarchy.svg The waste hierarchy from reduce down to dispose Reduce first. Landfill is the most expensive answer on the list. https://plumbmatemastery.co.uk/blog/level-1-copper-pipework-joints-clips.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-2-copper-pipework-joints-clips-figures.svg Key figures for copper pipework for level 1 The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-106-soldered-joint.svg The six steps of making a soldered capillary joint Heat the fitting, not the solder. Capillary action does the rest. https://plumbmatemastery.co.uk/blog/level-1-plastic-pressure-pipework.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-2-plastic-pressure-pipework-figures.svg Key figures for plastic pressure pipework for level 1 The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-109-plastic-joint.svg The steps of making a push fit joint in plastic pressure pipe The insert is the part people forget, and the joint fails without it. https://plumbmatemastery.co.uk/blog/level-1-low-carbon-steel-pipework.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-2-low-carbon-steel-pipework-figures.svg Key figures for low carbon steel pipework for level 1 The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-110-thread.svg The steps of cutting a thread with stocks and dies Square start, plenty of oil, and check the length before you seal it. https://plumbmatemastery.co.uk/blog/level-1-installation-repair-maintenance-plumbing.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-111-valves.svg Which valve goes where in a plumbing system A stopcock works against pressure. A gate valve does not. https://plumbmatemastery.co.uk/images/blog/l1-2-installation-repair-maintenance-plumbing-figures.svg Key figures for installation, repair and maintenance for level 1 The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-plumbing-science-water-heat-materials.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-2-plumbing-science-water-heat-materials-figures.svg Key figures for plumbing science for level 1 The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-113-heat-transfer.svg The three ways heat moves and where each one appears in plumbing A radiator is misnamed — most of what it does is convection. https://plumbmatemastery.co.uk/blog/level-1-five-key-trades-construction-site.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-101-fix-order.svg The order of trades on site through first fix and second fix Knowing who waits for whom is most of getting on with the other trades. https://plumbmatemastery.co.uk/images/blog/l1-m1-five-key-trades-construction-site-figures.svg Key figures for the five key trades on a building site, and where the plumber fits The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-hazards-on-a-building-site.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m1-hazards-on-a-building-site-figures.svg Key figures for hazards on site The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-types-of-construction-company.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-101-business-types.svg The four ways a construction business can be owned Limited means the company is a separate legal person. That is the whole point of it. https://plumbmatemastery.co.uk/images/blog/l1-m1-types-of-construction-company-figures.svg Key figures for sole trader, partnership or limited company The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-construction-team-job-roles.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m1-construction-team-job-roles-figures.svg Key figures for the construction team The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-plumbing-industry-bodies-jib-aphc.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m1-plumbing-industry-bodies-jib-aphc-figures.svg Key figures for industry bodies The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-101-bodies.svg The industry bodies and what each one actually does Ask what each body can make you do, and they stop blurring together. https://plumbmatemastery.co.uk/blog/level-1-employment-rights-construction.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m1-employment-rights-construction-figures.svg Key figures for your rights at work The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-discrimination-at-work-construction.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m1-discrimination-at-work-construction-figures.svg Key figures for discrimination at work The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-cscs-nvq-plumbing-career-path.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-101-career.svg The qualification route from Level 1 through to NVQ and CSCS The classroom part is not the bottleneck. On-site experience is. https://plumbmatemastery.co.uk/images/blog/l1-m1-cscs-nvq-plumbing-career-path-figures.svg Key figures for getting qualified The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-units-of-measurement-plumbing.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m10-units-of-measurement-plumbing-figures.svg Key figures for units of measurement The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-states-of-water-and-expansion.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-113-temperatures.svg The four key water temperatures and what happens at each Four figures, and 4 °C is the one that explains why ice floats. https://plumbmatemastery.co.uk/images/blog/l1-m10-states-of-water-and-expansion-figures.svg Key figures for the states of water The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-properties-of-water-ph-scale-capillary.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m10-properties-of-water-ph-scale-capillary-figures.svg Key figures for the properties of water The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-113-water-properties.svg The properties of water and what each one does to plumbing Hard and soft water cause different problems — neither is simply better. https://plumbmatemastery.co.uk/blog/level-1-materials-and-their-properties.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m10-materials-and-their-properties-figures.svg Key figures for materials and their properties The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-heat-transfer-and-insulation.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-113-heat-transfer.svg The three ways heat moves and where each one appears in plumbing Conduction through solids, convection through fluids, radiation across a space. https://plumbmatemastery.co.uk/images/blog/l1-m10-heat-transfer-and-insulation-figures.svg Key figures for heat The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-health-and-safety-law-hasawa.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m2-health-and-safety-law-hasawa-figures.svg Key figures for safety law The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-safety-signs-shapes-and-colours.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/prohibition-sign.gif A prohibition sign: a red circle with a diagonal bar Prohibition. Red circle, bar through it — you must not do this. https://plumbmatemastery.co.uk/images/blog/l1-102-signs.svg Safety sign shapes and colours and what each combination means The shape carries the meaning, which is why it works in any language. https://plumbmatemastery.co.uk/images/blog/l1-m2-safety-signs-shapes-and-colours-figures.svg Key figures for safety signs The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/coshh-corrosive.png The GHS corrosive pictogram Corrosive. The pictogram tells you the harm; the data sheet tells you what to do about it. https://plumbmatemastery.co.uk/images/warning-sign.gif A warning sign: a yellow triangle with a skull and crossbones Warning. Yellow triangle — a hazard is present. https://plumbmatemastery.co.uk/images/mandatory-sign.gif A mandatory sign: a blue circle showing eye protection Mandatory. Blue circle — you must do this. https://plumbmatemastery.co.uk/blog/level-1-dangerous-situations-preventing-accidents.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m2-dangerous-situations-preventing-accidents-figures.svg Key figures for dangerous situations and how accidents are actually prevented The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-102-hierarchy.svg The hierarchy of control from eliminate down to PPE Work from the top down. PPE is where you end up, not where you start. https://plumbmatemastery.co.uk/blog/level-1-asbestos-dangers-where-it-hides.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-102-asbestos.svg The key facts about asbestos, where it hides and what to do It harms by inhalation, and it takes twenty years to show. https://plumbmatemastery.co.uk/images/blog/l1-m2-asbestos-dangers-where-it-hides-figures.svg Key figures for asbestos The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-ppe-eight-items-and-their-purpose.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m2-ppe-eight-items-and-their-purpose-figures.svg Key figures for ppe The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/insulating-gloves.png Several types of protective glove The glove has to match the harm: cut, chemical, thermal or electrical. One pair does not cover all four. https://plumbmatemastery.co.uk/blog/level-1-manual-handling-lifting-safely.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m2-manual-handling-lifting-safely-figures.svg Key figures for manual handling The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-102-manual-handling.svg The four steps of safe manual handling, with technique last The assessment is the step that decides whether the lift should happen at all. https://plumbmatemastery.co.uk/blog/level-1-accidents-emergencies-first-aid-riddor.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m2-accidents-emergencies-first-aid-riddor-figures.svg Key figures for accidents and emergencies The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-102-riddor.svg RIDDOR reporting thresholds and the first aid roles Seven days off normal duties, reported within fifteen. https://plumbmatemastery.co.uk/blog/level-1-working-at-height-ladders-checks.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-102-height.svg Working at height duties and the ladder figures Avoid, prevent, reduce — and no minimum height anywhere in it. https://plumbmatemastery.co.uk/images/blog/l1-m2-working-at-height-ladders-checks-figures.svg Key figures for working at height The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/scaffold-tower.jpg A mobile scaffold tower A tower is a workplace, not access. Erecting one needs the training the ticket proves. https://plumbmatemastery.co.uk/blog/level-1-fire-triangle-classes-extinguishers.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m2-fire-triangle-classes-extinguishers-figures.svg Key figures for fire The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/no-flames.gif A no naked flames prohibition sign Where this is up, a blowtorch is not an option. Press fit, or a permit. https://plumbmatemastery.co.uk/images/blog/l1-102-extinguishers.svg Which extinguisher suits which class of fire CO₂ is the one for live electrical equipment. Water never is. https://plumbmatemastery.co.uk/blog/level-1-saving-water-and-electricity-in-homes.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m3-saving-water-and-electricity-in-homes-figures.svg Key figures for saving water and electricity The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-types-of-energy-high-low-zero-carbon.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-103-energy.svg Which energy sources count as high, low and zero carbon Solar thermal is low and solar photovoltaic is zero — worth knowing why. https://plumbmatemastery.co.uk/images/blog/l1-m3-types-of-energy-high-low-zero-carbon-figures.svg Key figures for types of energy The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-reducing-carbon-emissions-from-buildings.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m3-reducing-carbon-emissions-from-buildings-figures.svg Key figures for carbon emissions from buildings, and the six measures that bring them down The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-renewable-installations-explained.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m3-renewable-installations-explained-figures.svg Key figures for renewable installations The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-working-practices-saving-energy-materials.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m3-working-practices-saving-energy-materials-figures.svg Key figures for working practices that save energy and materials The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-103-waste-hierarchy.svg The waste hierarchy from reduce down to dispose Everything in this outcome is an application of this one order. https://plumbmatemastery.co.uk/blog/level-1-disposing-of-waste-safely-duty-of-care.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m3-disposing-of-waste-safely-duty-of-care-figures.svg Key figures for disposing of waste safely The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-hazardous-non-hazardous-inert-waste-weee.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-103-waste-classes.svg The three classes of waste and what goes in each Same product, different class — it depends what is in it. https://plumbmatemastery.co.uk/images/blog/l1-m3-hazardous-non-hazardous-inert-waste-weee-figures.svg Key figures for hazardous, non-hazardous and inert waste — and what weee covers The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-hand-tools-for-plumbers.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/combination-pliers.jpg A pair of combination pliers Combination pliers. Check the insulation and the pivot before every use. https://plumbmatemastery.co.uk/images/blog/l1-m4-hand-tools-for-plumbers-figures.svg Key figures for hand tools The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/adjustable-spanner.png An adjustable spanner An adjustable spanner: right size first, and pull towards the fixed jaw. https://plumbmatemastery.co.uk/images/stillson-wrench.png A Stillson pattern pipe wrench A Stillson grips harder the more you pull. For steel pipe, never on a chromed fitting. https://plumbmatemastery.co.uk/blog/level-1-power-tools-and-their-faults.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/socket-tester.jpg A plug-in socket tester A socket tester finds a reversed polarity or a missing earth before the tool does. https://plumbmatemastery.co.uk/images/blog/l1-104-power-tools.svg Power tool voltages, protection and the common faults A fuse protects the cable. An RCD protects you. https://plumbmatemastery.co.uk/images/blog/l1-m4-power-tools-and-their-faults-figures.svg Key figures for power tools The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/110v_hammer_drill.jpg A 110 volt hammer drill A 110 V tool on site: centre tapped, so the worst shock to earth is 55 V. https://plumbmatemastery.co.uk/blog/level-1-using-power-tools-safely.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-104-power-tools.svg Power tool voltages, protection and the common faults Two devices, two completely different jobs. https://plumbmatemastery.co.uk/images/blog/l1-m4-using-power-tools-safely-figures.svg Key figures for using power tools safely The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/insulated-wire-cutters.jpeg A pair of VDE insulated cable cutters Insulated to VDE. The rating is on the handle, and it is not a substitute for isolating. https://plumbmatemastery.co.uk/blog/level-1-drill-bits-and-screw-heads.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m4-drill-bits-and-screw-heads-figures.svg Key figures for drill bits and screw heads The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog-hand-tools-5.png The five common screw drives: Torx, slotted, pozidriv, Phillips and Allen, with matching bits Five drives and their bits. Phillips is designed to cam out; pozidriv is designed not to. https://plumbmatemastery.co.uk/images/blog/l1-104-screw-heads.svg Screw drive types and head shapes, and the difference between them The drive is how you turn it. The head is how it sits. Two separate choices. https://plumbmatemastery.co.uk/blog/level-1-fixings-and-what-to-use-on-each-surface.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-104-fixings.svg Which fixing to use on brick, block, plasterboard and timber Find the timber behind the plasterboard if you possibly can. https://plumbmatemastery.co.uk/images/blog/l1-m4-fixings-and-what-to-use-on-each-surface-figures.svg Key figures for fixings The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog-installation-6.jpg Sleeve anchor bolts For anything heavy, the fixing goes into the masonry, not the plaster. https://plumbmatemastery.co.uk/blog/level-1-reading-the-job-first-and-second-fix.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m4-reading-the-job-first-and-second-fix-figures.svg Key figures for reading the job The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-floors-lifting-boards-and-risks.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-104-lifting-boards.svg How to lift a floor safely without cutting a cable Cut over the joist. A board cut between joists has nothing to land on. https://plumbmatemastery.co.uk/images/blog/l1-m4-floors-lifting-boards-and-risks-figures.svg Key figures for floors The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-notching-and-drilling-joists.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m4-notching-and-drilling-joists-figures.svg Key figures for notching and drilling joists The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-104-joists.svg The permitted zones and limits for notching and drilling a joist The zones exist because of where a joist is in tension and where it is in compression. https://plumbmatemastery.co.uk/blog/level-1-customers-and-other-trades.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/extension-ladder.jpg An extension ladder against a building Access equipment goes up before the work starts, not once you are already reaching. https://plumbmatemastery.co.uk/images/blog/l1-m4-customers-and-other-trades-figures.svg Key figures for customers and other trades The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-tools-for-above-ground-drainage.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/plastic-pipe-slice.png A plastic pipe slice Cut it with a slice or shears — a hacksaw leaves a ragged end and swarf. https://plumbmatemastery.co.uk/images/blog/l1-m5-tools-for-above-ground-drainage-figures.svg Key figures for tools for drainage work, and why every cut end gets deburred The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-guttering-fittings-named.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/gutter-components-209.jpg The named components of a guttering system Every part of a gutter run has a name, and the exam asks for them. https://plumbmatemastery.co.uk/images/blog/l1-m5-guttering-fittings-named-figures.svg Key figures for rainwater guttering The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/fascia-bracket-209.jpg A fascia bracket A fascia bracket screws to the board. A rise and fall bracket lets you set the gradient. https://plumbmatemastery.co.uk/blog/level-1-installing-guttering-fall-and-expansion.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/gutter-bracket-spacing-150mm.jpg Bracket spacing at a gutter joint A bracket within 150 mm of every joint and outlet, and no more than 1 m apart. https://plumbmatemastery.co.uk/images/blog/l1-m5-installing-guttering-fall-and-expansion-figures.svg Key figures for installing guttering The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/gutter-union-expansion-gap.jpg A gutter union showing the expansion gap The gap is marked inside the fitting. Push it fully home and PVC-U has nowhere to go. https://plumbmatemastery.co.uk/images/blog/l1-105-guttering.svg Guttering fall, bracket spacing and expansion figures Too few brackets and it sags, holds water, and eventually overflows. https://plumbmatemastery.co.uk/blog/level-1-waste-pipe-sizes-and-fittings.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-105-waste-sizes.svg Waste pipe sizes for common appliances Undersize it and the appliance siphons its own trap out. https://plumbmatemastery.co.uk/images/blog/l1-m5-waste-pipe-sizes-and-fittings-figures.svg Key figures for waste pipe The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/p-trap-photo-209.jpg A P trap A P trap: horizontal outlet, and the commonest trap on a basin or sink. https://plumbmatemastery.co.uk/images/bottle-trap-photo-209.jpg A bottle trap A bottle trap unscrews to clean, but it blocks more readily than a tubular one. https://plumbmatemastery.co.uk/blog/level-1-jointing-waste-pipe-solvent-push-fit.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/pushfit-coupler.jpg A push fit waste coupling A ring seal takes the movement. Lubricate it, and leave the expansion gap. https://plumbmatemastery.co.uk/images/blog/l1-105-jointing.svg Comparison of solvent weld and push fit jointing for waste pipe One is permanent, one moves. Choose by whether the pipe needs to. https://plumbmatemastery.co.uk/images/blog/l1-m5-jointing-waste-pipe-solvent-push-fit-figures.svg Key figures for jointing waste pipe The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-clipping-waste-pipe-spacing.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m5-clipping-waste-pipe-spacing-figures.svg Key figures for clipping waste pipe The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-106-clip-spacing.svg Clip spacing for copper, plastic and low carbon steel Plastic needs roughly three times the support copper does. https://plumbmatemastery.co.uk/blog/level-1-gases-and-heat-producing-equipment.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m6-gases-and-heat-producing-equipment-figures.svg Key figures for gases and heat producing equipment The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/acetylene-hose.png An acetylene hose Colour coded by gas, and inspected along its whole length. https://plumbmatemastery.co.uk/images/blowtorch.png A blowtorch Check the hose, the seal and the flame before it goes anywhere near a joint. https://plumbmatemastery.co.uk/images/blog/l1-106-hot-works.svg Hot works precautions before lighting a torch The fire watch continues after the flame goes out, not just during the work. https://plumbmatemastery.co.uk/blog/level-1-tools-for-copper-pipework.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m6-tools-for-copper-pipework-figures.svg Key figures for tools for copper The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-copper-tube-fittings-and-clips.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/copper-tee.jpg A copper tee fitting A tee: three ends, and the branch is where most of the leaks start. https://plumbmatemastery.co.uk/images/blog/l1-m6-copper-tube-fittings-and-clips-figures.svg Key figures for copper tube, fittings and clips The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-106-clip-spacing.svg Clip spacing for copper, plastic and low carbon steel Unclipped pipe bangs because it is free to move when the flow starts and stops. https://plumbmatemastery.co.uk/blog/level-1-joining-copper-capillary-compression.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m6-joining-copper-capillary-compression-figures.svg Key figures for joining copper The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/capillary-solder-ring.jpg An integral solder ring capillary fitting The solder is already in the ring. Heat the fitting and it draws right round. https://plumbmatemastery.co.uk/images/blog/l1-106-soldered-joint.svg The six steps of making a soldered capillary joint Clean, flux, heat the fitting. Capillary action pulls the solder in. https://plumbmatemastery.co.uk/blog/level-1-tools-for-plastic-pressure-pipe.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m7-tools-for-plastic-pressure-pipe-figures.svg Key figures for tools for plastic pressure pipe The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/plastic-pipe-slice.png A plastic pipe slice Square, clean and burr free. Anything else will not seal. https://plumbmatemastery.co.uk/blog/level-1-joining-plastic-pressure-pipe-inserts.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/push-fit-fitting.png A plastic push fit fitting A grab ring holds it, an O ring seals it, and the insert stops the pipe collapsing. https://plumbmatemastery.co.uk/images/blog/l1-m7-joining-plastic-pressure-pipe-inserts-figures.svg Key figures for joining plastic pressure pipe, and the insert everybody forgets The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-109-plastic-joint.svg The steps of making a push fit joint in plastic pressure pipe Without the insert the pipe collapses under the compression of the fitting. https://plumbmatemastery.co.uk/blog/level-1-plastic-pipe-sizes-clips-and-support.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m7-plastic-pipe-sizes-clips-and-support-figures.svg Key figures for plastic pipe The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-106-clip-spacing.svg Clip spacing for copper, plastic and low carbon steel Three times the clips. That is the comparison the exam wants. https://plumbmatemastery.co.uk/blog/level-1-tools-for-low-carbon-steel.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m8-tools-for-low-carbon-steel-figures.svg Key figures for tools for low carbon steel The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-joining-low-carbon-steel.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/gf-steel-coupling.png A malleable iron steel coupling Malleable iron fittings for LCS — threaded, not soldered. https://plumbmatemastery.co.uk/images/blog/l1-m8-joining-low-carbon-steel-figures.svg Key figures for joining low carbon steel The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/union-connector.jpg A union connector A union is the joint you can undo. Without one, a repair means cutting the pipe. https://plumbmatemastery.co.uk/images/blog/l1-106-clip-spacing.svg Clip spacing for copper, plastic and low carbon steel Steel is the stiffest of the three, so it needs the fewest clips. https://plumbmatemastery.co.uk/blog/level-1-cutting-a-thread-stocks-and-dies.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-110-thread.svg The steps of cutting a thread with stocks and dies Cutting oil is not optional — it cools the die and clears the swarf. https://plumbmatemastery.co.uk/images/blog/l1-m8-cutting-a-thread-stocks-and-dies-figures.svg Key figures for cutting a thread The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-where-water-comes-from.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m9-where-water-comes-from-figures.svg Key figures for where water comes from The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l1-111-supply-stages.svg The six stages of water supply from source to distribution Six stages, in order, turning raw water into wholesome water. https://plumbmatemastery.co.uk/images/cwsc-and-fe-cistern.jpg A cold water storage cistern alongside a feed and expansion cistern Two cisterns in a loft: the big one stores water, the small one feeds the heating. https://plumbmatemastery.co.uk/blog/level-1-cold-and-hot-water-systems.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-111-direct-indirect.svg Comparison of direct and indirect cold water systems Ask what feeds the bathroom basin and you have your answer. https://plumbmatemastery.co.uk/images/blog/l1-m9-cold-and-hot-water-systems-figures.svg Key figures for cold and hot water systems The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/direct-cylinder.jpg Labelled diagram of a direct hot water cylinder with immersion heater A direct cylinder: the water you draw off is the water that was heated. https://plumbmatemastery.co.uk/images/double-feed-indirect-cylinder.jpg An indirect hot water cylinder with its heating coil An indirect cylinder: a coil carries the primary water, and the two never mix. https://plumbmatemastery.co.uk/blog/level-1-valves-in-plumbing-systems.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/gate-valve-photo.jpg A gate valve A gate valve: full bore when open, but only for low pressure work. https://plumbmatemastery.co.uk/images/full-bore-lever-valve.jpg A full bore lever ball valve with compression ends A lever valve: full bore, so it barely restricts the flow, and you can see at a glance whether it is open. https://plumbmatemastery.co.uk/images/blog/l1-m9-valves-in-plumbing-systems-figures.svg Key figures for valves The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/gate-valve-wedge.jpg The wedge inside a gate valve The wedge is what wears. A gate valve that will not shut off has usually lost it. https://plumbmatemastery.co.uk/images/blog/l1-111-valves.svg Which valve goes where in a plumbing system Fitting a gate valve on the main is the classic mistake. https://plumbmatemastery.co.uk/blog/level-1-types-of-tap-explained.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/non-rising-pillar-tap.jpg A pair of pillar taps with shrouded heads Pillar taps. Non-rising spindle, so the head stays put as it opens. https://plumbmatemastery.co.uk/images/ceramic-disc-taps.jpg A pair of taps with lever operated ceramic disc cartridges Ceramic discs: a quarter turn, and no washer to wear out. https://plumbmatemastery.co.uk/images/blog/l1-m9-types-of-tap-explained-figures.svg Key figures for taps The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/biflow-mixer.jpg A bi-flow kitchen mixer tap Bi-flow: hot and cold stay separate right to the spout, so a stored supply cannot mix with the main. https://plumbmatemastery.co.uk/blog/level-1-float-operated-valves.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m9-float-operated-valves-figures.svg Key figures for float operated valves The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/part1-fov.jpg A BS 1212 Part 1 float operated valve Part 1: the traditional brass piston valve, still found everywhere. https://plumbmatemastery.co.uk/images/part2-fov.png A BS 1212 Part 2 float operated valve Part 2: a diaphragm instead of a piston, so far less to seize. https://plumbmatemastery.co.uk/blog/level-1-repairing-taps-valves-float-valves.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/reseating-tool1.jpg A tap reseating tool with its cutters Where the seat itself is pitted, a new washer will not hold. Recut the seat. https://plumbmatemastery.co.uk/images/blog/l1-m9-repairing-taps-valves-float-valves-figures.svg Key figures for repairing taps, valves and float valves The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-1-noise-faults-in-water-systems.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m9-noise-faults-in-water-systems-figures.svg Key figures for noise faults The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/full-bore-lever-valve.jpg A quarter turn lever valve A quarter turn valve shuts fast, which is exactly what starts water hammer. https://plumbmatemastery.co.uk/blog/level-1-planned-and-unplanned-maintenance.html 2026-09-03 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l1-m9-planned-and-unplanned-maintenance-figures.svg Key figures for planned and unplanned maintenance, and why speed matters The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-water-regulations-inspection-and-liability.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m1-water-regulations-inspection-and-liability-figures.svg Key figures for when the water inspector turns up The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-331-liability.svg The three questions asked on a Water Regulations inspection Three questions, asked in this order, decide almost every inspection. https://plumbmatemastery.co.uk/images/blog/l3-331-fluid-categories.svg The five fluid categories from wholesome water to serious health hazard Category 2 is an aesthetic change only. Calling it a health hazard is the classic slip. https://plumbmatemastery.co.uk/blog/level-3-water-regulations-notification-and-certificates.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-331-notification.svg The Regulation 5 notification figures and thresholds The traps are in what is not on the list, and in how narrow the exemption really is. https://plumbmatemastery.co.uk/images/blog/l3-m1b-water-regulations-notification-and-certificates-figures.svg Key figures for who do you have to tell? regulation 5, building control and the ten working days The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-cisterns-multi-storey-buildings.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m1b-cisterns-multi-storey-buildings-figures.svg Key figures for cisterns in tall buildings The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/cistern-abcd.jpg A protected cold water storage cistern with its cover, warning pipe and float valve A protected cistern: rigid cover, screened vent and warning pipe, and access to service it. https://plumbmatemastery.co.uk/images/blog/l3-331-multi-storey.svg How to get water up a multi-storey building The main gets you about ten storeys. Everything above that is designed. https://plumbmatemastery.co.uk/blog/level-3-booster-sets-pumps-vessels-and-switches.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-331-pump-duty.svg How a pump duty is worked out, with a worked power calculation Static lift, friction and residual pressure — then the power follows. https://plumbmatemastery.co.uk/images/blog/l3-m1b-booster-sets-pumps-vessels-and-switches-figures.svg Key figures for booster sets The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-private-water-supplies-sources-treatment-layouts.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m1b-private-water-supplies-sources-treatment-layouts-figures.svg Key figures for private water supplies The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-331-treatment-barriers.svg The multiple barrier principle for treating a private water supply No single barrier is trusted on its own, and ultraviolet always goes last. https://plumbmatemastery.co.uk/blog/level-3-specialist-taps-valves-and-shower-pumps.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m1b-specialist-taps-valves-and-shower-pumps-figures.svg Key figures for specialist taps, flow and pressure valves, and why the shower valve weeps The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-backflow-fluid-categories-and-air-gaps.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-331-fluid-categories.svg The five fluid categories from wholesome water to serious health hazard The category downstream picks the device — always the highest one. https://plumbmatemastery.co.uk/images/blog/l3-m1b-backflow-fluid-categories-and-air-gaps-figures.svg Key figures for backflow The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-331-air-gaps.svg The air gap types and the tap gaps that get confused AUK2 is set by the tap. AUK3 is set by the bore. That is the whole difference. https://plumbmatemastery.co.uk/level-3/img/bf-air-gaps-aa-ab-ad.svg Types AA, AB and AD drawn in section showing what each gap is measured to, and the split between gaps at a cistern and gaps under a tap All three measure down from the lowest point of the discharge orifice. What differs is where the measurement stops: the spillover level for a type AA, the critical level of the weir for a type AB, which is why an AB cistern may have a lid and an AA may not. A type AA gap is 20 mm or twice the inlet bore, whichever is greater, and nothing may ever bridge it. https://plumbmatemastery.co.uk/blog/level-3-mechanical-backflow-devices-and-cross-connections.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-331-air-gaps.svg The air gap types alongside the mechanical devices No mechanical device reaches fluid category 5 — which is why the gaps exist. https://plumbmatemastery.co.uk/images/blog/l3-m1b-mechanical-backflow-devices-and-cross-connections-figures.svg Key figures for rpz valves, check valves and cross connections The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/double-check-valve.jpg A double check valve Two independent check valves in one body — fluid category 3, and no higher. https://plumbmatemastery.co.uk/blog/level-3-cold-water-design-information-and-drawings.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m1b-cold-water-design-information-and-drawings-figures.svg Key figures for where the design comes from The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-cold-water-sizing-cisterns-pipes-and-pumps.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/ballofix-valve.jpg A small isolating service valve A service valve at every appliance, so one repair does not drain the building. https://plumbmatemastery.co.uk/images/blog/l3-m1b-cold-water-sizing-cisterns-pipes-and-pumps-figures.svg Key figures for sizing a cold water system The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-331-loading-units.svg Loading units and design flow rates for common appliances One loading unit is 0.1 l/s. Everything else is built off that. https://plumbmatemastery.co.uk/images/blog/l3-331-pump-accumulator.svg When to specify a pump and when to specify an accumulator Not enough pressure and not enough flow are different faults with different answers. https://plumbmatemastery.co.uk/blog/level-3-cold-water-fault-diagnosis-and-isolation.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m1b-cold-water-fault-diagnosis-and-isolation-figures.svg Key figures for diagnosing a cold water fault The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-331-isolation.svg What the rules require of water that stands still in a system Seven days, and a year. Two thresholds worth remembering exactly. https://plumbmatemastery.co.uk/blog/level-3-cold-water-repairs-and-recommissioning.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m1b-cold-water-repairs-and-recommissioning-figures.svg Key figures for repairing a cold water system The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-331-isolation.svg Maintenance intervals for backflow devices and standing water Every device on this list has an interval attached to it. https://plumbmatemastery.co.uk/blog/level-3-cold-water-inspection-filling-and-pressure-testing.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m1b-cold-water-inspection-filling-and-pressure-testing-figures.svg Key figures for inspect dry, fill slowly, test once The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-331-pressure-test.svg How to pressure test cold water pipework in metal and in plastics On plastics the gauge falls because the pipe creeps. That is not a leak. https://plumbmatemastery.co.uk/blog/level-3-flushing-disinfection-and-performance-testing.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-331-flush-disinfect.svg The order of testing, flushing and disinfecting a water system Tested, flushed, then disinfected. Schedule 2 sets that order and it does not move. https://plumbmatemastery.co.uk/images/blog/l3-m1b-flushing-disinfection-and-performance-testing-figures.svg Key figures for flush, disinfect, prove The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-cold-water-records-certificates-and-handover.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-331-records.svg What goes into a commissioning record and how long it is kept The statutory defence needs both the approved contractor and the certificate. https://plumbmatemastery.co.uk/images/blog/l3-m1b-cold-water-records-certificates-and-handover-figures.svg Key figures for the commissioning record, the certificates, and what handover actually means The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-types-of-hot-water-system.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m2-types-of-hot-water-system-figures.svg Key figures for every hot water system, and what decides which one you fit The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-332-vented-figures.svg Key figures for a vented hot water system The hazard on an unvented system is heat, not pressure — the boiling point moves with it. https://plumbmatemastery.co.uk/images/cylinder-with-coil.jpg An indirect hot water cylinder showing its heating coil The coil keeps the primary water and the stored water apart. They never mix. https://plumbmatemastery.co.uk/blog/level-3-hot-water-design-temperatures-and-tmvs.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-332-temperature-chain.svg The chain of hot water temperatures from legionella growth to the outlet Every figure in the chain exists to stay out of the growth range without scalding anybody. https://plumbmatemastery.co.uk/images/blog/l3-m2-hot-water-design-temperatures-and-tmvs-figures.svg Key figures for hot in the store, cool at the tap The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/tmv.jpg A thermostatic mixing valve Fitted as close to the outlet as practicable, with strainers and isolation each side. https://plumbmatemastery.co.uk/images/blog/l3-332-tmv2-tmv3.svg Comparison of TMV2 and TMV3 thermostatic mixing valve schemes The scheme follows the setting, not the appliance. https://plumbmatemastery.co.uk/blog/level-3-secondary-circulation-dead-legs-and-trace-heating.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-332-dead-legs.svg Dead leg limits and insulation requirements on hot water distribution The uninsulated maximum falls as the pipe gets bigger, because the volume rises faster. https://plumbmatemastery.co.uk/images/blog/l3-m2-secondary-circulation-dead-legs-and-trace-heating-figures.svg Key figures for long dead legs The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-unvented-inlet-control-group-and-expansion.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-332-inlet-group.svg The order of components in an unvented inlet control group Each one is where it is because of what the one before it does. https://plumbmatemastery.co.uk/images/blog/l3-m2-unvented-inlet-control-group-and-expansion-figures.svg Key figures for the unvented inlet group The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/unvented-pressure-relief.jpg An expansion relief valve The expansion relief valve on the cold side. A cold discharge points straight at it. https://plumbmatemastery.co.uk/blog/level-3-unvented-safety-devices-and-discharge-pipework.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/unvented-temperature-pressure-relief.jpg A temperature and pressure relief valve with its probe The probe sits in the stored water. Factory fitted, and never relocated. https://plumbmatemastery.co.uk/images/blog/l3-332-thermal-protection.svg The three tiers of thermal protection on an unvented cylinder Functional or safety? That is the line examiners test, and the thermostat is on the wrong side of it. https://plumbmatemastery.co.uk/images/blog/l3-m2-unvented-safety-devices-and-discharge-pipework-figures.svg Key figures for three levels of safety, and the discharge pipe that has more rules than any other The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/discharge-pipe-d1-d2.webp The discharge arrangement from a relief valve through a tundish to outside D1 is short and steep to the tundish. D2 is long and shallow to a safe termination. https://plumbmatemastery.co.uk/images/blog/l3-332-discharge.svg Discharge pipework figures for D1, the tundish and D2 D1 is short and steep. D2 is long and shallow. The tundish sits between them, visible. https://plumbmatemastery.co.uk/blog/level-3-hot-water-taps-outlets-shower-pumps-and-accumulators.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m2-hot-water-taps-outlets-shower-pumps-and-accumulators-figures.svg Key figures for at the outlet The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-332-pressure-figures.svg Pressure and flow figures for hot water outlets, pumps and accumulators A pump taken straight off the main is capped at 12 litres a minute. https://plumbmatemastery.co.uk/blog/level-3-choosing-a-hot-water-system.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-332-sizing-cylinder.svg How to size a hot water cylinder from the daily demand Three published methods, three different answers — which is why you state the one you used. https://plumbmatemastery.co.uk/images/blog/l3-m2-choosing-a-hot-water-system-figures.svg Key figures for choosing a hot water system The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-hot-water-information-sources-and-calculations.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m2-hot-water-information-sources-and-calculations-figures.svg Key figures for the documents, the demand, and every hot water calculation worked through The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-332-sizing-cylinder.svg How to size a hot water cylinder from the daily demand Stratified or mixing changes the answer by more than ten per cent. https://plumbmatemastery.co.uk/blog/level-3-hot-water-installation-requirements.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-332-pressure-figures.svg Pressure and flow figures for an unvented hot water installation Static pressure tells you very little. The dynamic figure is what the system runs on. https://plumbmatemastery.co.uk/images/blog/l3-m2-hot-water-installation-requirements-figures.svg Key figures for installing hot water The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-hot-water-inspection-testing-and-flushing.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m2-hot-water-inspection-testing-and-flushing-figures.svg Key figures for inspecting, testing, flushing and disinfecting a hot water system The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-332-soundness.svg The steps of soundness testing hot water pipework Flushed first, then filled with drinking water, then held at one and a half times working pressure. https://plumbmatemastery.co.uk/blog/level-3-hot-water-setting-to-work-and-handover.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-332-commissioning-order.svg The order of commissioning an unvented hot water system A filled system hides the pre-charge, which is why it is checked before anything else. https://plumbmatemastery.co.uk/images/blog/l3-m2-hot-water-setting-to-work-and-handover-figures.svg Key figures for setting an unvented system to work, and handing it over properly The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-hot-water-fault-diagnosis.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m2-hot-water-fault-diagnosis-figures.svg Key figures for diagnosing a hot water fault The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-332-fault-signature.svg How to read a discharge to tell a pressure fault from a temperature fault Cold means pressure. Hot means temperature. That halves the search before you touch anything. https://plumbmatemastery.co.uk/blog/level-3-hot-water-checks-repairs-and-handover.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-332-vessel-check.svg How to check and recharge an expansion vessel on a hot water system What comes out of the schrader valve tells you which fault you have. https://plumbmatemastery.co.uk/images/blog/l3-m2-hot-water-checks-repairs-and-handover-figures.svg Key figures for servicing and repairing a hot water system, and handing it back safely The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/cylinder-thermostat.jpg A cylinder thermostat strapped to a cylinder A quarter to a third of the way up, against bare metal, set to about 60 °C. https://plumbmatemastery.co.uk/blog/level-3-types-of-central-heating-system.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m3-types-of-central-heating-system-figures.svg Key figures for one-pipe, two-pipe, microbore, open vented and sealed The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-333-one-two-pipe.svg Comparison of one pipe and two pipe central heating systems One pipe cannot be balanced out of its problem — it is a limit of the design. https://plumbmatemastery.co.uk/images/blog/l3-333-design-figures.svg The core central heating design temperatures and limits Six figures that decide most of a heating design. https://plumbmatemastery.co.uk/blog/level-3-central-heating-controls-and-zoning.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m3-central-heating-controls-and-zoning-figures.svg Key figures for heating controls and zoning The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/2-port-valve.jpg A two port motorised zone valve Motor open, spring return. A failed one is usually found by hand, not by meter. https://plumbmatemastery.co.uk/images/3-port-valve.jpg A three port motorised valve One valve, two zones. Five cores means mid-position; three means diverter. https://plumbmatemastery.co.uk/images/blog/l3-333-plan-types.svg Grid comparing S-plan, Y-plan and W-plan heating control systems Count the valves and count the cores — that identifies the system every time. https://plumbmatemastery.co.uk/blog/level-3-underfloor-heating-design-and-manifolds.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-333-underfloor-limits.svg Underfloor heating surface temperature and output limits The surface temperature caps the output. No flow temperature gets you past it. https://plumbmatemastery.co.uk/images/blog/l3-m3-underfloor-heating-design-and-manifolds-figures.svg Key figures for underfloor heating The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/underfloor-heating-layout.jpg An underfloor heating pipe layout Flow meters on one bar, actuators on the other. Balance on the flow, control on the return. https://plumbmatemastery.co.uk/blog/level-3-low-loss-headers-and-hydraulic-separation.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-333-separation.svg Hydraulic separation options in order of preference Every step down this list costs efficiency, so take the highest one that works. https://plumbmatemastery.co.uk/images/blog/l3-m3-low-loss-headers-and-hydraulic-separation-figures.svg Key figures for low loss headers The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-heating-design-factors-and-sources.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m3-heating-design-factors-and-sources-figures.svg Key figures for where a heating design starts The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-heat-loss-and-heat-gain-calculations.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-333-heat-loss.svg The steps of a room heat loss calculation Fabric and ventilation, added together. Ventilation is the half people underestimate. https://plumbmatemastery.co.uk/images/blog/l3-m3-heat-loss-and-heat-gain-calculations-figures.svg Key figures for heat loss worked properly The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-heating-calculations-emitters-pipes-and-pumps.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/column-radiator-208.jpg A cast iron column radiator A column radiator holds far more water, so it responds far more slowly. https://plumbmatemastery.co.uk/images/blog/l3-333-emitter-sizing.svg How to size a radiator from a room heat loss and a catalogue output A catalogue figure is quoted at ΔT50. Your system is almost certainly not running there. https://plumbmatemastery.co.uk/images/blog/l3-m3-heating-calculations-emitters-pipes-and-pumps-figures.svg Key figures for from watts to millimetres The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-positioning-and-fixing-heating-components.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m3-positioning-and-fixing-heating-components-figures.svg Key figures for where everything goes The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/circulating-pump-photo.jpg A heating circulating pump On a vertical pipe, pumping downwards, and never with the motor pointing down. https://plumbmatemastery.co.uk/images/blog/l3-333-open-vented-order.svg The order of boiler, vent, cold feed and pump on an open vented system Boiler, vent, cold feed, pump — with the vent and feed within 150 mm. https://plumbmatemastery.co.uk/images/bypass-valve.jpg An automatic bypass valve Taken off the flow immediately after the pump, back to the return. https://plumbmatemastery.co.uk/blog/level-3-underfloor-heating-installation.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-333-uf-constructions.svg Comparison of screeded and timber underfloor heating constructions Thermal mass is the real difference, and it decides how the system is controlled. https://plumbmatemastery.co.uk/images/blog/l3-m3-underfloor-heating-installation-figures.svg Key figures for installing underfloor heating The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-sealed-systems-vessel-safety-valve-and-filling.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/feed-expansion.jpg A feed and expansion arrangement On a sealed system the vessel does what the feed and expansion cistern used to. https://plumbmatemastery.co.uk/images/blog/l3-m3-sealed-systems-vessel-safety-valve-and-filling-figures.svg Key figures for sealed systems The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-333-sealed-system.svg Sealed system figures for the vessel, safety valve and filling loop The charge pressure comes off the static head, not off a default. https://plumbmatemastery.co.uk/blog/level-3-supplying-and-connecting-heating-controls.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m3-supplying-and-connecting-heating-controls-figures.svg Key figures for the electrical side The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-333-certification.svg Which electrical certificate applies to heating controls work Altering a circuit and adding one are different jobs with different paperwork. https://plumbmatemastery.co.uk/blog/level-3-heating-wiring-diagrams-and-circuit-testing.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m3-heating-wiring-diagrams-and-circuit-testing-figures.svg Key figures for reading heating wiring diagrams, and the tests that prove them The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-333-plan-types.svg Grid comparing S-plan, Y-plan and W-plan heating control systems Five cores means mid-position. Three means diverter. https://plumbmatemastery.co.uk/blog/level-3-safe-isolation-and-pre-installation-checks.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-333-safe-isolation.svg The six steps of safe isolation on a heating circuit Identify, confirm, inform, isolate, secure, prove dead. https://plumbmatemastery.co.uk/images/blog/l3-m3-safe-isolation-and-pre-installation-checks-figures.svg Key figures for safe isolation The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-wiring-filling-and-testing-heating-controls.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m3-wiring-filling-and-testing-heating-controls-figures.svg Key figures for wiring, filling and proving a heating control system The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-333-sealed-system.svg Sealed system figures for the vessel, safety valve and filling loop The pump is isolated before filling, so it cannot run dry. https://plumbmatemastery.co.uk/blog/level-3-heating-inspection-filling-testing-and-flushing.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-333-five-conditions.svg The five conditions a system must meet before commissioning starts Cured, complete, closed up, wired, checked — in that order. https://plumbmatemastery.co.uk/images/blog/l3-m3-heating-inspection-filling-testing-and-flushing-figures.svg Key figures for filling, soundness testing and flushing a heating system The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/auto-air-vent-photo.jpg An automatic air vent At the high points, where the air actually collects — not where it is convenient. https://plumbmatemastery.co.uk/blog/level-3-heating-setting-to-work-balancing-and-handover.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m3-heating-setting-to-work-balancing-and-handover-figures.svg Key figures for setting to work The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-333-balancing.svg The steps of balancing a heating system and setting it to work The temperature drop is a measurement that tells you the flow rate. https://plumbmatemastery.co.uk/blog/level-3-central-heating-fault-finding.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-333-fault-order.svg The order of work when fault finding on central heating Gather, verify, consult, test. Skipping to the last one is how parts get replaced for nothing. https://plumbmatemastery.co.uk/images/blog/l3-m3-central-heating-fault-finding-figures.svg Key figures for finding a heating fault The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-putting-a-heating-fault-right.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-333-putting-right.svg The seven steps of putting a central heating fault right Notification comes second, and safe isolation is not optional. https://plumbmatemastery.co.uk/images/blog/l3-m3-putting-a-heating-fault-right-figures.svg Key figures for putting a heating fault right The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-types-of-sanitation-system.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m4-types-of-sanitation-system-figures.svg Key figures for sanitary pipework The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/bottle-trap-photo-209.jpg A bottle trap A bottle trap: easy to clean, but it blocks more readily than a tubular one. https://plumbmatemastery.co.uk/images/blog/l3-334-seal-depths.svg Trap seal depths by appliance and the 25 mm that must remain The depth fitted varies. The depth that has to survive does not. https://plumbmatemastery.co.uk/images/blog/l3-334-branch-limits.svg Maximum unventilated branch lengths by pipe size and gradient Steepen the gradient and the permitted length falls — which surprises people. https://plumbmatemastery.co.uk/images/primary-stack-diagram-209.jpg Diagram of a primary ventilated stack system One stack, no branch vents — the arrangement most domestic work uses. https://plumbmatemastery.co.uk/blog/level-3-sanitary-facilities-and-equipment.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/macerator.jpeg A WC with a macerator unit behind it Only where a gravity WC also exists. It is never the only WC in the property. https://plumbmatemastery.co.uk/images/blog/l3-334-macerator.svg The six requirements for installing a macerator correctly Rise first and fall afterwards. Doing it the other way round is the classic fault. https://plumbmatemastery.co.uk/images/blog/l3-m4-sanitary-facilities-and-equipment-figures.svg Key figures for macerators, lifters, wet rooms, wc flushing and urinals The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-cesspools-and-septic-tanks.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m4-cesspools-and-septic-tanks-figures.svg Key figures for cesspools and septic tanks The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-334-cesspool-septic.svg Comparison of cesspool and septic tank capacities and routines One stores and one treats, which is why the capacities differ by so much. https://plumbmatemastery.co.uk/blog/level-3-choosing-a-sanitation-system-and-appliances.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m4-choosing-a-sanitation-system-and-appliances-figures.svg Key figures for choosing the system The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-334-activity-space.svg Activity space and appliance size requirements The appliance fits. The space in front of it is what gets forgotten. https://plumbmatemastery.co.uk/blog/level-3-sizing-sanitary-pipework.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m4-sizing-sanitary-pipework-figures.svg Key figures for sizing sanitary pipework The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-334-branch-limits.svg Maximum unventilated branch lengths by pipe size and gradient Three remedies when a branch is too long: upsize, anti-vacuum trap, or ventilate. https://plumbmatemastery.co.uk/images/blog/l3-334-stack-sizing.svg Worked example sizing a stack for six flats using the discharge unit method Five steps, one formula, and a stack size at the end of it. https://plumbmatemastery.co.uk/blog/level-3-rainwater-and-roof-drainage.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m4-rainwater-and-roof-drainage-figures.svg Key figures for rainwater The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-334-roof-drainage.svg Roof drainage pitch factors, capacity reductions and spacing limits Pitch, wall contribution and outlet position all move the answer. https://plumbmatemastery.co.uk/blog/level-3-sanitation-fault-finding.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m4-sanitation-fault-finding-figures.svg Key figures for finding a sanitation fault The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/self-siphonage-mechanism.jpg Diagram of self-siphonage emptying a trap seal Self-siphonage: the discharge runs full bore and pulls the seal out behind it. https://plumbmatemastery.co.uk/images/blog/l3-334-seal-loss.svg The six mechanisms by which a trap loses its water seal Six mechanisms, six different cures. Naming it correctly is the whole diagnosis. https://plumbmatemastery.co.uk/images/aav-component-2-209.png An air admittance valve It lets air in and nothing out. It never replaces the terminal at the top of the stack. https://plumbmatemastery.co.uk/blog/level-3-putting-a-sanitation-fault-right.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m4-putting-a-sanitation-fault-right-figures.svg Key figures for clearing blockages, correcting workmanship and re-testing The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-334-clearing.svg Clearing techniques ordered from least to most invasive Work down the list. Starting at the bottom damages pipework that was never the problem. https://plumbmatemastery.co.uk/blog/level-3-commissioning-sanitary-pipework.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-334-commissioning-order.svg The order of commissioning sanitary pipework The order is not negotiable — each stage assumes the one before it passed. https://plumbmatemastery.co.uk/images/blog/l3-m4-commissioning-sanitary-pipework-figures.svg Key figures for commissioning sanitary pipework The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-sanitation-records-handover-and-notification.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m4-sanitation-records-handover-and-notification-figures.svg Key figures for records, handover and notification for sanitation work The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-334-notification.svg The routes for notifying building control about sanitation and drainage work Which route you take depends on whether you hold a scheme registration. https://plumbmatemastery.co.uk/blog/level-3-inspecting-and-air-testing-sanitary-pipework.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m4-inspecting-and-air-testing-sanitary-pipework-figures.svg Key figures for on site The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/drain-plug-component-209.png An expanding drain test plug The plug seals the end, and its own bung is covered with a little water for the air seal. https://plumbmatemastery.co.uk/images/blog/l3-334-air-test.svg The five steps of running an air test on sanitary pipework 38 mm water gauge for three minutes, and no drop at all. https://plumbmatemastery.co.uk/blog/level-3-performance-testing-sanitary-appliances.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-334-performance-test.svg How to performance test a trap seal and judge the result Three discharges, and the worst result is the one that counts. https://plumbmatemastery.co.uk/images/blog/l3-m4-performance-testing-sanitary-appliances-figures.svg Key figures for performance testing The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-micro-renewables-and-heat-pumps.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-335-micro-renewables-and-heat-pumps-figures.svg Key figures for micro-renewables and heat pumps The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/comp-refrigeration-circuit.svg The four components of the refrigeration circuit The four components themselves, and the loop that connects them. https://plumbmatemastery.co.uk/images/blog/l3-335-refrigeration-cycle.svg The four parts of the refrigeration cycle and what each one does Every heat pump is this loop. Name the part and you can name what it does. https://plumbmatemastery.co.uk/images/blog/l3-335-collectors.svg The four ground collector arrangements with their depths and spacings Which one you use is decided by the land available, not by preference. https://plumbmatemastery.co.uk/blog/level-3-solar-thermal-systems.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-335-solar-thermal-systems-figures.svg Key figures for solar thermal The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-335-solar-geometry.svg How orientation, tilt and shading affect solar thermal output A roof does not have to be perfect. Shading costs far more than a few degrees of azimuth. https://plumbmatemastery.co.uk/images/blog/comp-flat-plate.svg A labelled flat plate solar collector Glazing over a selective absorber, with a header top and bottom. https://plumbmatemastery.co.uk/blog/level-3-rainwater-harvesting-and-greywater.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-335-rainwater-steps.svg The four steps of rainwater harvesting: collection, filtration, storage and reuse Four steps, and a figure attached to each of them. https://plumbmatemastery.co.uk/images/blog/l3-335-rainwater-harvesting-and-greywater-figures.svg Key figures for rainwater harvesting and greywater The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-335-reuse-order.svg The order in which reclaimed water may be used, from WC flushing to external spray Collect the cleanest first and use it for the dirtiest job first. https://plumbmatemastery.co.uk/blog/level-3-surveying-a-building-for-renewables.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-335-survey.svg The order of a renewables survey from confirming authorisation to selecting the plant Selection comes last, off a measured heat loss. https://plumbmatemastery.co.uk/images/blog/l3-335-surveying-a-building-for-renewables-figures.svg Key figures for surveying for renewables The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-planning-and-permitted-development-for-renewables.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-335-planning-and-permitted-development-for-renewables-figures.svg Key figures for permitted development The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-335-pd-heat-pumps.svg The old and current permitted development rules for domestic heat pumps in England Quoting the old figures is the commonest error on this topic. https://plumbmatemastery.co.uk/blog/level-3-building-regulations-and-standards-for-renewables.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-335-which-parts.svg Grid of which Approved Documents apply to heat pumps, water reuse and biomass J is the one people add to a heat pump by mistake — there is no combustion. https://plumbmatemastery.co.uk/images/blog/l3-335-building-regulations-and-standards-for-renewables-figures.svg Key figures for which parts apply, what mcs is, and how the work is installed The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-cop-scop-and-spf-explained.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-335-cop-scop-and-spf-explained-figures.svg Key figures for cop, scop and spf The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-335-cop-scop.svg Comparison of COP as a single point measurement against SCOP and SPF over time COP sells the product. SPF is what the customer actually pays to run. https://plumbmatemastery.co.uk/blog/level-3-heat-pump-benefits-and-limitations.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/comp-ashp-unit.svg A labelled air source heat pump outdoor unit Airflow, meltwater and noise are all decided by where this ends up. https://plumbmatemastery.co.uk/images/blog/l3-335-heat-pump-benefits-and-limitations-figures.svg Key figures for heat pumps compared The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-335-collectors.svg The four ground collector arrangements with their depths and spacings Land, not preference, decides which of these you can have. https://plumbmatemastery.co.uk/blog/level-3-solar-thermal-benefits-and-limitations.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-335-solar-thermal-benefits-and-limitations-figures.svg Key figures for solar thermal The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/comp-evacuated-tube.svg A labelled evacuated tube solar collector The vacuum is what gives the evacuated tube its low heat loss coefficient. https://plumbmatemastery.co.uk/images/blog/l3-335-stagnation.svg Stagnation temperatures for flat plate and evacuated tube collectors The fluid is a consumable. Judging it by pH and smell is part of a service. https://plumbmatemastery.co.uk/blog/level-3-water-conservation-benefits-and-limitations.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-335-water-conservation-benefits-and-limitations-figures.svg Key figures for rainwater against greywater The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-335-reuse-order.svg The order in which reclaimed water may be used External spray is last because it carries the strictest quality standard. https://plumbmatemastery.co.uk/blog/level-3-comparing-renewable-technologies-and-advising.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-335-carbon.svg Carbon figures for natural gas, grid electricity and biomass Grid electricity carries more carbon per kWh than gas, which is why SCOP decides the answer. https://plumbmatemastery.co.uk/images/blog/l3-335-comparing-renewable-technologies-and-advising-figures.svg Key figures for comparing the technologies The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-clients-and-site-communication.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m6-clients-and-site-communication-figures.svg Key figures for clients, the chain of command and getting a change in writing The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-336-who-authorises.svg Flow chart showing who may authorise a change to the work on a domestic job and on a contract On a contract the authority is named in the contract. It is never the occupant or another trade. https://plumbmatemastery.co.uk/images/blog/l3-336-spoken-written.svg Comparison of spoken and written communication on site Spoken communication is faster; written communication is the only kind you can produce later. https://plumbmatemastery.co.uk/images/blog/l3-336-variation-order.svg The five stages of a variation order from identifying the change to building it The order is fixed: nothing is built until the priced change has been accepted in writing. https://plumbmatemastery.co.uk/blog/level-3-roles-on-a-construction-site.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m6-roles-on-a-construction-site-figures.svg Key figures for who does what on site The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-336-roles.svg Table of roles on the client's side and the contractor's side of a building services job Two sides, two reporting lines. Instructions come down your own. https://plumbmatemastery.co.uk/images/blog/l3-336-craft-levels.svg Qualification levels and the supervision that goes with each Supervision loosens as the qualification rises, but delegation always follows competence. https://plumbmatemastery.co.uk/blog/level-3-health-and-safety-legislation-on-site.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/mandatory-sign.gif A mandatory sign requiring eye protection Blue circle: you must. The duty behind it is section 7 — you follow what is provided. https://plumbmatemastery.co.uk/images/blog/l3-m6-health-and-safety-legislation-on-site-figures.svg Key figures for the act, cdm, the regulations under them, and the certificates The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/blog/level-3-risk-assessments-explained.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m6-risk-assessments-explained-figures.svg Key figures for risk assessments The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-336-five-steps.svg The five steps of a risk assessment in the order the HSE sets them out Learn them in this order. Guessing that recording comes third is the classic error. https://plumbmatemastery.co.uk/images/blog/l3-336-risk-bands.svg Risk scoring bands from minor through significant to critical The band decides the action — and 16 to 25 means work stops. https://plumbmatemastery.co.uk/images/blog/l3-336-hierarchy.svg The hierarchy of control from eliminate down to personal protective equipment The same order appears as avoid, assess, reduce for manual handling and avoid, prevent, reduce for work at height. https://plumbmatemastery.co.uk/blog/level-3-site-hazards-substances-handling-height.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/coshh-corrosive.png The GHS corrosive pictogram The pictogram names the harm. The data sheet tells you the equipment, the spill kit and the disposal route. https://plumbmatemastery.co.uk/images/blog/l3-m6-site-hazards-substances-handling-height-figures.svg Key figures for site hazards The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-336-spillage.svg The four-step spillage procedure: contain, protect, absorb, dispose Contain first. Reaching for a hose is how a spill becomes a prosecution. https://plumbmatemastery.co.uk/images/blog/l3-336-height-figures.svg Key figures for work at height, ladders, harnesses and abrasive wheels The figures examiners come back to, and the two metre rule that has not applied for years. https://plumbmatemastery.co.uk/images/blog/l3-336-safe-isolation.svg The seven steps of safe isolation, ending with re-proving the voltage indicator Labelling and the final re-prove are the two steps that get dropped. https://plumbmatemastery.co.uk/blog/level-3-method-statements.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m6-method-statements-figures.svg Key figures for method statements The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-336-ra-vs-ms.svg Comparison of what a risk assessment does and what a method statement does They answer different questions, and the second is impossible without the first. https://plumbmatemastery.co.uk/images/blog/l3-336-ms-headings.svg The five standard headings of a method statement and what belongs under each A rejected method statement costs a start date, so the layout matters as much as the content. https://plumbmatemastery.co.uk/blog/level-3-variations-and-change-control.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m6-variations-and-change-control-figures.svg Key figures for variations The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-336-variation-causes.svg Grid of variation causes against who usually carries the cost The cause points at the cost, which is why the record names what changed and why. https://plumbmatemastery.co.uk/images/blog/l3-336-who-authorises.svg Flow chart showing who may authorise a change to the work An apprentice asked for a change on site records it and passes it up. They do not decide. https://plumbmatemastery.co.uk/images/blog/l3-336-variation-order.svg The five stages of a variation order, covering both cost and the revised completion date Price the change, state the new completion date, get it accepted, then build it. https://plumbmatemastery.co.uk/blog/level-3-monitoring-safety-and-cost-on-site.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m6-monitoring-safety-and-cost-on-site-figures.svg Key figures for monitoring safety and cost The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-336-riddor.svg Key safety monitoring figures including the RIDDOR seven day and fifteen day rules The RIDDOR trigger is days off normal duties, not the type of injury. https://plumbmatemastery.co.uk/images/blog/l3-336-storage-waste.svg Material storage requirements alongside how to deal with wastage on site Materials that survive until they are fitted, and waste that is measured rather than tolerated. https://plumbmatemastery.co.uk/blog/level-3-progress-quality-and-managing-people.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m6-progress-quality-and-managing-people-figures.svg Key figures for progress, quality and people The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-336-checking-order.svg The order of checking and accepting work, from operative check through to protecting the finish Acceptance is obtained and verified before the finished work is protected — not after. https://plumbmatemastery.co.uk/images/blog/l3-336-formal-procedure.svg Handling poor work informally first, then the formal procedure Formal action only once informal action has been tried and recorded without success. https://plumbmatemastery.co.uk/blog/level-3-types-of-work-programme.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m6-types-of-work-programme-figures.svg Key figures for work programmes The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-336-programme-types.svg Which method of recording a work programme suits which kind of job The job decides the tool. A service schedule is the only one that answers how often. https://plumbmatemastery.co.uk/images/blog/l3-336-bar-chart.svg A seven week bar chart programme showing the critical path and an activity with float Read it in three passes: dates and durations, then dependencies, then the critical path. https://plumbmatemastery.co.uk/blog/level-3-planning-the-work.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m6-planning-the-work-figures.svg Key figures for planning the work The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-336-document-order.svg The order of precedence when statute, a manufacturer instruction and a British Standard disagree Statute first, then whichever of the instruction and the standard is more demanding. https://plumbmatemastery.co.uk/images/blog/l3-336-notification.svg Notification and consent figures for building control and the water undertaker Consent takes time you have to allow for at planning stage. https://plumbmatemastery.co.uk/blog/level-3-pricing-and-presenting-the-work.html 2026-09-05 monthly 0.7 https://plumbmatemastery.co.uk/images/blog/l3-m6-pricing-and-presenting-the-work-figures.svg Key figures for pricing the work The examinable numbers from this article, in one place. https://plumbmatemastery.co.uk/images/blog/l3-336-contract-types.svg The three contract pricing methods and who carries the risk under each Match the method to how well the scope is known, and price the risk as well as the work. https://plumbmatemastery.co.uk/images/blog/l3-336-worked-price.svg A worked price build-up from labour and materials through overheads to profit Build it line by line and the price can be defended, adjusted and reused. https://plumbmatemastery.co.uk/images/blog/l3-336-quote-estimate.svg Comparison of a quotation and an estimate A customer who thought they had a fixed price and received a variable one has a complaint. https://plumbmatemastery.co.uk/blog/level-3-cold-water-systems-unit-331-guide.html 2026-09-05 monthly 0.8 https://plumbmatemastery.co.uk/images/blog/l3-hub-331.svg The five parts of Level 3 Unit 331 cold water system planning and design Five parts, assessed five different ways. Revise them differently too. https://plumbmatemastery.co.uk/blog/level-3-hot-water-systems-unit-332-guide.html 2026-09-05 monthly 0.8 https://plumbmatemastery.co.uk/images/blog/l3-hub-332.svg The five parts of Level 3 Unit 332 hot water system planning and design The temperature chain is the spine of the whole unit. https://plumbmatemastery.co.uk/blog/level-3-central-heating-systems-unit-333-guide.html 2026-09-05 monthly 0.8 https://plumbmatemastery.co.uk/images/blog/l3-hub-333.svg The five parts of Level 3 Unit 333 central heating system design The biggest unit, and the one with the heaviest calculation load. https://plumbmatemastery.co.uk/blog/level-3-sanitation-systems-unit-334-guide.html 2026-09-05 monthly 0.8 https://plumbmatemastery.co.uk/images/blog/l3-hub-334.svg The five parts of Level 3 Unit 334 sanitation system design Everything in it protects 25 mm of water in a trap. https://plumbmatemastery.co.uk/blog/level-3-environmental-technology-unit-335-guide.html 2026-09-05 monthly 0.8 https://plumbmatemastery.co.uk/images/blog/l3-hub-335.svg The five parts of Level 3 Unit 335 environmental technology Efficiency figures and compliance rules carry most of the marks. https://plumbmatemastery.co.uk/blog/level-3-site-procedures-unit-336-guide.html 2026-09-05 monthly 0.8 https://plumbmatemastery.co.uk/images/blog/l3-hub-336.svg The five parts of Level 3 Unit 336 site procedures The unit that decides whether the other five ever get built on time.