Plumbing Terms Glossary

Plumbing Terms Glossary

TMV (Thermostatic Mixing Valve): A device that blends hot and cold water to maintain a safe and consistent outlet temperature, preventing scalding. Thermostatic Mixing Valves are found in hospitals, child care centres and in care compliant bathrooms.

Tempering Valve: Similar to a TMV, this valve regulates water temperature, ensuring it remains within a safe range (in Victoria, tempering valves are set at 50°C to reduce the risk of scalding.

Nipple: A short piece of pipe used to connect two fittings or fixtures. Nipples come in various lengths and are essential for plumbing connections.

Trap: A U-shaped pipe beneath sinks, showers, and toilets designed to prevent sewer gases from entering the home while allowing water and waste to flow out.

Backflow Prevention: A device that prevents the reverse flow of water into the public water supply, protecting against contamination.

Ball Valve: A type of valve with a spherical disc that controls the flow of water when rotated.

Check Valve: A one-way valve that allows water to flow in one direction only, preventing backflow.

Soldering: A method of joining pipes and fittings using melted metal (solder) to create a secure, leak-proof connection.

Plumber’s Tape (Teflon Tape): A thin, white tape wrapped around threaded pipe connections to create a watertight seal.

P-trap: A common type of trap shaped like the letter “P” used under sinks to trap debris and prevent clogs while allowing water to flow and the ‘trap’ stops foul smelling gas coming through the pipes.

S-trap: An s-shaped pipe with a water ‘trap’ to stope sewer smells coming up through the pipes. It is bulkier and connected to the floor, unlike the p-trap which connects to the wall.

Water Hammer: The loud banging noise that can occur when water suddenly stops or changes direction in pipes.

Water Meter: A device that measures the volume of water consumed by a property, used for billing purposes, always located at the boundary line of a property.

Bidet: A bidet or bidet hand sprayer are a jet of spray used to wash one’s nether regions after going to the toilet and are used instead of toilet paper.

Boundary Shaft: Connects internal sewer to water authority sewer and should terminate at ground level. Don’t ever cover your boundary shaft.

Overflow Relief Gully: Prevents sewage from overflowing into your home and should also never be covered.

Floor Waste: commonly located in bathrooms and laundries to act as a drain in the floor to avoid water building up and flooding.

Pan: a toilet bowl

Cistern: The tank at the back of the toilet where the water is held for a flush.

Mini Stop: This tap connects to the cistern and can be used as an isolation tap in case a toilet needs removing or is leaking. Should be installed on every toilet and flick mixer.

Inlet Valve: This allows water to flow freely into the tank until full (when faulty the water may keep flowing)

Pressure Reducing Valve (PRV): Designed to open and release pressure, should be installed on every water meter at 500kPa which ensures internal tapware warranties.

Pressure and Temperature Relief Valve (PTR):  Designed to open and release pressure from a hot water system when the system exceeds a certain set point of either pressure or temperature.

Sacrificial Anode: This is a long metal rod and via electrolysis shields a water tank by corroding in place of a hot water system’s tank.

Thermocouple: It is in a hot water system tank and monitors if a pilot light has gone out. If the flame is out, the thermocouple will detect this and shut off the gas supply to the hot water unit until the flame is relit.

Duo Valve: The duo valve consists of two distinct valves. The first one is known as the stop tap, which is used to shut off the water supply to the heater. The second valve is a non-return valve, designed to prevent hot water from the tank from flowing back into the cold-water pipe.

Frost Protection Valve: Frost protection valves are designed to protect the hot water service’s solar panels by ensuring they don’t freeze when the outside air temperature drops. When the air temperature drops to between 3ᵒ and 4ᵒ, the thermostatic element opens in the valve and warm water is flushed through the solar storage tank in the panels which ensures the panels are less likely to freeze.

Common Plumbing Terms

Navigating the world of plumbing is much more accessible when you understand the terminology. This plumbing jargon glossary provides a foundation for homeowners and clients to communicate effectively with plumbers, make informed decisions, and maintain their plumbing. Remember, if you ever have questions or need assistance with your plumbing needs, the team at McCarthy Plumbing Group is always here to help on 03 9931 0905.