pressure that resists the flow of fluid in a piping system.

plumbing fixture’s separate vent in a building drainage system.

the process of cleaning a filter by reversing the flow of water through it – the dirt is sent to the waste disposal.

a valve that uses a ball to seal against a seat to stop flow in one direction.

spherical assembly allowing pivot rotation for many bathroom and shower accessories.

the fill valve that controls the flow of water from the water supply line into a gravity-operated toilet tank.

relating to handicap access – e.g., a shower enclosure with minimal bottom track and opening to ease wheelchair access.

a substance that releases hydroxyl ion when dissolved in water.

a central heating boiler is used to increase the water temperature in your central heating system. Newer boilers have improvements for energy saving. You can get different types of boilers from combi boilers, condensing boilers to system boilers.

is used as a means of escape to the outside for carbon dioxide and other gasses in a central heating system.

British Thermal Units used to measure the output of heat from a radiator. It is defined as the amount of energy or heat energy needed to raise the temperature of one pound of water by one degree Fahrenheit.

a serviceable valve that allows water to flow through it when open and stops the flow when closed.

total amount of greenhouse gas emissions created by an individual, organization, event, service, or product – such as a heating system – expressed by carbon dioxide equivalent.

A system for warming a building by heating water or air in one place and circulating it through pipes and radiators or vents.

shut-off valve used with tub/shower tap that is activated by turning a slotted stem with a screwdriver – also known as a screwdriver stop or a service stop.

a type of back flow preventer installed in a pipe that allows water to flow in one direction

rainwater storage tank, often underground, also a toilet storage vessel.

a variety of geothermal heat pump that passes a mixture of water and antifreeze through a closed loop of pipe buried in the ground to collect heat.

a central heating system which is closed to the external water supply. It will have a device that will not allow water to expand when heated. Most modern systems are designed this way as it helps prevent oxidisation from fresh water. Most closed systems will have rust inhibitor and boiler noise silencer added to it.

a more traditionally styled radiator. Popular for its older style and versatility in being sprayed a custom colour.

uses fins to effectively distribute hot water throughout the radiator allowing it a larger heat output on a smaller surface area.

Also known as a combination boiler, a combi boiler is a compact, self-contained unit which combines both a central heating water heat exchange and a domestic water heater in one. Unlike a vented heating and hot water system, a combi does not store hot water. Instead, it heats water as and when required either directly from the cold mains (for the domestic hot water) or within a pressurised 'sealed' central heating loop.

also referred to as a condenser or outdoor unit, is part of an ASHP or HVAC unit that is located outside. It compresses and pumps refrigerant to meet cooling needs, and contains the condenser coil.

a component of air conditioning units that is involved in the basic refrigeration cycle that adds or removes heat from the system. The condenser is the hot side of an air conditioner or heat pump.

the movement caused within a fluid. Hotter liquids and therefore less dense will cause materials to rise, and colder, denser materials to sink under the influence of gravity, which consequently results in transfer heat via convection.

the barrier built into a trapway of a toilet that controls the water level in the bowl.

a device that opens and closes to regulate how much air flows through vents, or ducts in a ducted heat pump system.

Equipment that reduces the level of humidity from the air. It works by cooling air to the point where water turns to liquid from vapor form, which is then removed.

process of reducing water to a non-mineral state by passing it over a bed of resins.

placed over HVAC/ASHP ductwork. The diffuser separates air and distributes evenly in different directions.

tube inside water heater that sends cold water to the bottom of the tank.

a system that pulls outside air for combustion and vents combustion gases directly outside without a chimney.

tee fitting that allows direct flow in one direction by use of an internal baffle.

a flanged adaptor connecting a basket strainer to the drainpipe with a dishwasher inlet.

device that allows drainage of stored contents from a water heater.

consists of specialized pipes or channels that direct airflow (including supply air, return air and exhaust air) within a home or building.

a twin valve (hot and cold) with a single on/off lever used for washing machines.

Drainage, Waste and Vent systems, which remove wastewater.

the pressure when the water is flowing.

Energy Factor – a measure of the overall efficiency rating of the water heater based on the model’s recovery, efficiency, stand-by loss, and energy input.

sometimes called an ell – a fitting used to change the direction of rigid pipe or tubing.

the vertical distance between the level where fluid enters a pipe and the level where it leaves, which must be added to the total discharge head if the inlet is lower than the outlet and subtracted if the inlet is higher.

This stands for: Energy-related Products. This is a set of regulations that cover boilers, combination boilers, and water heaters

part of the refrigeration cycle that absorbs or adds heat to the system.

a safety device that is a tank designed to absorb excess pressure due to thermal expansion. Also known as an expansion vessel.

thermostatically controlled valve that controls liquid refrigerant.

the proper slope or pitch of a pipe for adequate drainage.

a pump that supplies water to a boiler.

material containing or derived from iron.

metal components that are fitted to the back of a standard panel radiator to help radiate heat.

a rib or rim for strength, which is present for guiding or for attachment to another object.

a more modern and contemporarily designed radiator. They are efficient and versatile. They use panels to heat a room.

paste applied to copper pipes and fittings before soldering to help the fusion process and prevent oxidation.

an opening through which outside air is drawn into your home to replace any air being removed by the ventilation and circulation systems.

the process of applying a coating of zinc to the finished product to provide corrosion protection – the coating can be applied by hot dipping or electrolytic deposition.

plug valve installed in the main gas line.

flat device, usually made of rubber, which is used to provide a watertight seal between metal joints.

refers to thickness of stainless steel and is commonly used in reference to quality grades on certain types of lavatories and sinks – for instance, 10 and 20-guage stainless steel sinks have gone through several polishing operations to establish a pristine finish.

also referred to as ground source, water source, or earth-coupled heat pumps, are a type of heat pump that collects thermal energy from the ground or a water source and transfers that energy inside a building to heat an indoor space.

Gallons Per Flush – the rate of water flow by which toilets and flush valves are measured and regulated.

wastewater filled with contaminants from sinks, showers, and bathtubs, but not from toilets.

the valve that controls water flow into the toilet tank.

natural water containing impurities in various proportions – traditional hardness is a measure of calcium or dissolved solids in a solution, measured in parts per million.

a heat transfer system.

the amount of thermal energy a heat pump releases into to warm a space. It is measured in BTUs.

occurs when heat is moved from one area to another, heating or cooling an indoor area.

restriction of heat loss through water connections to a tank.

this is a heat source and cooling device that can be used as both central heating and air conditioning. It uses the outside air to both provide heat and / or cold air when required. These devices can be good for energy efficiency.

a part of the HVAC system that conducts heat within the appliance.

this is a tank in some central heating systems that contains hot water that is used for taps and showers in the home. May also be known as a hot water cylinder.

Heating, Ventilation and Air Conditioning systems. More modern HVAC systems will also include air cleaning and moisture control features.

pressure that exists in a system containing non-compressible liquid.

the reaction of a salt with water to form an acid and a base.

system of forced hot water.

cold inlet tube designed to reduce sediment build-up and increase efficiency in a water heater.

the chemical group of ions, which is neutral or positively charged.

Inside Diameter – all pipes are sized according to their inside diameter.

rotating wheel with vanes found inside a centrifugal pump as it spins at high speed it draws fluids in and thrusts them under pressure to the discharge outlet.

the stream entering a unit, stream, or process, such as the hard water entering an ion exchange water softener.

a type of water heater, which heats supply as it passes through with no storage tank necessary – also known as a tankless heater.

an atom or group of atoms that function as a unit and have a positive or negative electrical charge due to the gain or loss of one or more electrons.

a reversible process in which ions are released from an insoluble permanent material in exchange for other ions in a surrounding solution; the direction of the exchange depends upon the affinities of the ion exchange for the ions present and the concentrations of the ions in the solution.

the process in which atoms gain or lose electrons – sometimes used as synonymous with dissociation; the separation of molecules in to charged ions in solutions.

Iron Pipe Size – standard pipe threads (the female IPS refers to internal pipe threads and the male IPS refers to external pipe threads).

device for separating grease and oil from drainage systems.

Lint, Dust and Oil.

Liquid Propane – a fuel for gas water heaters.

a sewage line that connects one sewage pipe with another.

water supply tube for a lavatory.

loss of fluid, usually due to mechanical breakdown or gasket wear.

a pipe that carries rainwater to the ground or sewer.

small commercial applications.

the substance that settles on the bottom of a water tank – also known as sediment.

a pair of copper tubes that connect a condenser to an evaporator so refrigerant can move between the two.

determines the size of heat pump necessary to provide proper temperature control in a desired area. Load calculations analyse factors including air volume of the desired area and the level of insulation in your home.

a nut fitted into a piece of pipe and screwed onto another pipe to join the two pieces.

a radiator valve which is used to balance the system by restricting the flow of water.

a class of toilet designed to flush using 1.6 gallons of water or less – also known as a water-saving toilet.

an industry standard for copper tubing defined by the tube wall thickness and identified by a red stripe.

Male Hose Threads – the threads on the outside of a connection.

A mini split is a ductless heat pump system in which an outdoor compressor unit is combined with multiple air handlers inside, usually one in every high-use room. It allows you to control the thermostat/ temperature in different areas of the home.

Male Iron Pipe Connection – standard external threads on pipe and fittings.

a device installed in a drain line between a toilet and the soil stack to reduce solids to liquid form.

an element in the Earth’s crust that makes water hard when dissolved, causing scale and insoluble soap curds.

the primary artery of water supply in a drain system.

fitting that is inserted into another fitting.

fittings made of cast iron, a metal which is soft and pliable.

mixes hot and cold water to achieve a specified delivery temperature.

rotary type backwash valve, which can replace up to six regular gate valves.

a pump that has more than one impeller.

nominal – usually refers to the inside diameter of trade sizes of copper pipe.

a colourless, odourless fuel (primarily consisting of methane) derived from the Earth – odours are added to aid in leak detection.

less than atmospheric pressure.

a short length of pipe installed between couplings or other fittings.

a tool used to unscrew sections of piping.

does not contain iron.

unsuitable for drinking.

round rubber washer used to create a watertight seal.

Outside Diameter – the diameter of a pipe measured from the outside edge.

a water heater that uses oil for its fuel source.

a geothermal heat pump that collects thermal energy from groundwater or water from another nearby source. It takes water from its source, moves it through a loop of pipe to collect the thermal energy, and transfers it back into the source.

the cost of running a water heater for a given period of time.

the opening through which water exits the pump.

the vertical tube inside a toilet tank that directs water into the bowl in case the ballcock malfunctions.

an air-handling unit, defined as either recirculating or once-through design, created for outdoor installation. They most often include, internally, their own heating and cooling devices.

Polybutylene – a flexible type of tubing used in water supply systems.

Polypropylene Pipe.

Parts Per Million – a unit of measure for impurities in water

Pressure Regulator – usually required if water pressure exceeds 80 PSI (pounds per square inch).

the nut that holds the stem of a tap in position.

a small burner used to ignite the main burner.

precisely vertical.

valve that rises perpendicularly to or from its seat.

the pressure or flow rate of water tunning through a system. Important to maintain the correct level of pressure required for your system to keep pipes clear of debris and running efficiently. Mains water pressure is also a phrase that is used to describe how much pressure is delivered from the water company to the home through its pipework.

pressure in a plumbing system – the unit of measure which is the vertical force exerted by water at a depth of one foot.

air which is mixed with gas before the gas leaves a burner port to burn – the ideal burning condition is generally 10 cubic feet of air per one cubic foot of gas.

the lowest water level reached during pumping operation.

a valve or tap that closes automatically when released manually or that is controlled by mechanical means for fast action closing.

a device which is used to heat a room. Liquid is pushed through exposed pipes and heated to warm a room. Available in many different styles, sizes and outputs.

water supplied to the plant before any treatment.

water that is red or brown in colour due to the presence of precipitated iron and/or iron bacteria.

a fitting that connects pipes of different sizes together.

transfers thermal energy from a colder space to a warmer space. This cycle is a reverse thermodynamic cycle that performs the opposite of the type of energy transfer that happens naturally without intervention from a system such as a heat pump or HVAC unit.

the tube that directs water from a ballcock into the overflow tube to refill bowl after a siphon break.

a valve that opens to relieve excess temperature.

a series of small holes in the underside of a toilet rim through which water flows to wash over the entire inner surface of the bowl.

a solution added to central heating systems to minimise the risk of rusting of metal components.

a device on a gas appliance that shuts off the gas supply to prevent a hazardous situation.

a thin layer of calcium on the interior of a tank that may prevent heat transfer.

the substance that settles on the bottom of a tank, also known as lime

Seasonal Energy Efficiency Ratio measures the energy efficiency of your air conditioning system. It measures the total cooling of your air conditioner or heat pump in BTUs compared with the energy output (in watt hours) used within the same period. The higher the SEER rating on your air conditioner, the more energy efficient it is, meaning lower energy costs to run it.

a pipe connecting two canals, through which water flows over a high point of gravity.

pipe that is passed through a wall for the purpose of inserting another pipe through it.

a connection made with compression fittings.

water that has a low calcium and magnesium content.

fitting that connects four pipes of the same diameter.

used on radiators with underside connections where the pips are coming up from the floor.

the valve that controls water supply to a toilet.

a drain ell fitting with a long radius that allows for smooth passage of waste.

an exposed plumbing fitting used to control the flow of water to a basin.

Threaded Both Ends.

Threaded and Coupled.

copper pipes that are connected to the radiator.

fitting with one plain end and one threaded female end.

the thread drilled into the designer radiator where the element or valves can easily fit into.

a rubber plug used to seal off sections of pipe to test for leaks.

a device that is used to control the amount of heat or temperature of a central heating system. TRV valves (thermostatic radiator valves) are devices that are used to control the room temperature in an individual room by controlling an individual radiator. Smart thermostats can also be installed and used as room thermostats in modern homes.

heat that is regulated to reach and maintain a desired temperature, usually using valves.

also referred to as towel warmers or towel rails. Often used in bathrooms as a specific place to warm towels and the room.

curved section of drain line that prevents sewer odours from escaping into the atmosphere – all features that have drains must have a P-trap installed, whilst toilets will have S-traps.

the waste arm portion of a drainage trap.

the U-bend portion of a drainage trap.

a flex adapter to connect drainpipes.

height of water in a toilet bowl at rest, providing a water seal to prevent sewer gases entering the home.

Thermostatic Radiator Valve – can automatically open and close necessary to achieve the pre-set room air temperature.

an industry standard for copper tubing defined by the tube wall thickness and identified by a red stripe.

a section of a waste pipe that is shaped like the letter U, which stops smells coming back into the property.

Ultra Low Flush – a widely used description of toilets that use 1.6 gallons per flush or less.

domed metal piece fastened to the bottom of a urinal to prevent debris from blocking the trapway of the unit.

percentage of hot water that can be drawn from a tank before the temperature drops to a point that it is no longer considered hot.

a device that regulates the flow of fluid.

the non-moving part of a valve – water flow is stopped when the movable element meets the valve seat.

A Variable Air Volume System is an HVAC system that provides a stable supply-air and temperature. It varies the airflow rate to meet the temperature requirements. They conserve energy by operating at lower fan speeds during times of lower temperature control demand.

a pipe that allows air into a drain system to balance air pressure and to prevent water in the traps from being siphoned off.

a vent pipe into which several vents connect – this leads to the vent stack and out of the building.

upper portion of the soil stack above the top fixture, through which gases and odours escape.

capable of vaporisation at a relatively low temperature.

refers to measurement by volume rather than weight.

flexible steel hose used for handheld shower sprays.

can cover any issues with radiators, an type of legal consumer promise to repair or replace products if broken or faulty within a set time frame.

an extension pipe usually used to extend a sink drain into a wall.

an assembly for a bathtub – the outlet at the top removes overflow water during tub filling and the drain at the bottom removes wastewater when the tub is drained.

drain stopper on a bathtub drain.

bathtub drain assembly.

main vertical pipe in a drainage system, extending one or more stories.

pipe from the water main.

these are cold water storage tanks that are often found in the lofts of houses. They hold cold water that is used to feed a central heating system.

a unit of power used to quantify the rate of energy transfer. Electricity is measured in Watts. It is equal to one joule of work per second.

drain or waste pipe that also acts for one or more fixtures on the same line.

maximum pressure of the operating system permissible.