Plumbing Glossary of Terms

 Glossary of Terms:  Plumbing | The Moran Group

[A]

ABS:

(Aristocraft bristone styrine)
Pipe used for waste, vent, and drain lines made of rigid plastic.


"A" Valve:

A valve used to manually shut gas off.

Access Panel:

For servicing purposes, an opening in a wall or ceiling near plumbing/electrical fixtures.

Acid:

Increases the concentration of hydrogen ions when dissolved in water. Acid dissolves common metals.

Acidity:

The measurement of acid concentration in water.

Acrylic:

For the purpose of waterproofing shower walls, it is a thermoplastic added to the surface of bathtubs and whirlpools.

Adaptor:

A fitting that allows for different pipe types to unite.

Aerator:

A device that adds air into flowing water from the end of a faucet to reduce splashing.

Airbreak:

A separation between the waste receptor and the fixture, appliance, or device that is indirectly connected.

Air Lock:

An air bubble in the line that blocks the flow of liquid on the suction side of the pump.

Alkali/Alkalinity:

The measurement of a water supply's ability to neutralize acids.

Ambient Temperature:

The average temperature of the air surrounding an appliance.

Angular Discharge Tube:

A tube that changes the direction of water flow by 90 degrees.

Angle Stop:

Used for emergency repair, it is a shutoff mechanism between water pipes and a faucet.

Anode Rod:

For the purpose of extending the life of the tank, it is a rod installed in a water heater that reduces corrosion.

Anti-Siphon:

Prevents water from trickling back into the supply that is feeding into a sprinkler system.

[B]

Backflow:

Flow of water or other substances into the distributing pipes of a potable supply of water from unintended sources.

Back Flow Preventer:

Prevents water or other substances from traveling back into the main distribution system. A backflow preventer is required for sprinkler systems, handheld showers, pullout faucet sprouts, kitchen sprayers, and other various devices.

Back Pressure:

Pressure against the flow of fluid in a piping system.

Back Siphonage:

The reverse flow of liquid due to a partial vacuum in the pipe.

Backup:

A clogged plumbing fixture due to drain stoppage.

Backwater Valve:

A valve within the sewer line that prevents sewage from reversing travel into the building.

Ball Check Valve:

A valve that utilizes a ball to seal an area and stop flow in a certain direction.

Ballcock:

The fill valve that determines the flow of water from the water supply line to the toilet tank.

Basin Wrench:

A long-handled wrench with jaws mounted on a swivel that can reach nuts in a previously installed sink.

Basket Strainer:

A strainer that fits into a sink or shower drain; it allows water to run through, but catches food, hair, and other objects to prevent clogging.

Bidet (pronounced Bid-day):

Consisting of a washing basin, hot/cold faucet, and sprayer, it is mounted near a toilet for the purpose of washing one's self.

Bleed:

Bleeding is the process of draining a pipe, tube, or hose of excess air.

Blowbag:

Blowbags are devices that clean drains. They are made up of a rubber bladder with a hose fitting on one end and a nozzle on the other. The blowbag is attached to a water hose and the hose is inserted into a clogged drainpipe. Water is expelled in pulses, forcing water through the clog.

Boiler:

A tank that heats water and turns it to steam for power or hot water.

Branch:

Various parts of a drain system, less the main, riser, or stack.

Branch Vent:

A vent that connects 1+ single vents with a vent stack.

BTU (British Thermal Unit):

A unit of heat energy needed to raise 1 lbs. of water by 1 degree.

[C]

Catch Basin:

A below ground container with a grate that collects storm water run-off. It catches debris, preventing water pollution.

Centerset:

A type of bathroom faucet with a spout and handles that are 4 inches apart.

Cesspool:

A cesspool is an underground excavation in the ground that receives the discharges of a drainage system. It retains the organic, solid matter and permits the liquids to seep through.

Check Valve:

A backflow preventer that only permits water to flow in one direction.

Circuit Vent:

A vertical vent drainage system run from the last two traps on a horizontal drain line to the main vent stack.

Cistern:

An underground rainwater storage container.

Cleanout Plug:

A cleanout plug provides access to a drain pipe to clear out obstructions.

Closet:

Another phrase for toilet.

Closet Auger:

A rod that can access the built-in trap to remove clogs.

Closet Bend:

A fitting mounted below the toilet, connecting the closet flange with the toilet drain.

Closet Flange:

A closet flange is an anchoring ring that attaches to the closet bend, and then is secured to the floor.

Cock:

A faucet or valve that regulates the flow of water; it is also known as a ballcock.

Common Vent:

A drain system within a building that connects 2+ fixture branches on the same level.

Compression Fitting:

A pipe connection where a nut and sleeve is placed over a tube, compressing it tightly around the tube as the nut is tightened; this forms a seal without soldering.

Compression Valve:

A valve used for water faucets. It opens and closes by raising and lowering a horizontal disk.

Coupling:

A hood for the vent pipe.

CPVC (Chlorinated Polyvinyl Chloride):

A plastic pipe used in some water supply systems, depending on code requirements.

Culvert:

Similar to a pipe, a construction of concrete that allows drainage underneath a road.

[D]

Desanco Fitting:

A compression adapter that attaches tubular brass fittings to PVC pipes.

Diaphragm:

To prevent debris build-up within the valve, a diaphragm is a flexible membrane within a valve that regulates water flow from the supply lines.

Dip Tube:

A tube with the purpose of bringing cold water to the bottom of the water heater tank.

Direct Tap:

A clamp on a branch line that takes it off of the main line.

Discharge Tube:

A discharge tube is an outlet tube that connects a disposer/sump pump to a drain line.

Disposal Field:

A series of trenches that distribute waste uniformly into the soil.

Dishwasher Tailpiece:

An adapter that unites a basket strainer to a drainpipe with a dishwasher inlet.

Diverter:

Used in showers, tubs, bidets, and sinks, they are valves that direct water to certain outlets.

Drip Leg:

A pipe with one closed end that is placed at a low point in the gas piping to collect and remove condensation.

Drum Trap:

This type of trap is no longer used. It was formerly used as a trap in sewer lines.

Duo Valve:

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

DWV:

Abbreviation for Drain, Waste and Vent.

[E]

E Coli:

An abbreviation for Escherichia Coli, a bacteria that reveals fecal contamination.

Earthquake Strap:

A metal strap that secures a water heater to a building's frame or foundation.

Efficiency:

Generally expressed as a percentage, a term that describes the ability to utilize energy.

Effluent:

Liquid waste from a Septic system.

Elbow:

A pipe fitting that changes the direction of the line.

Escutcheon:

A trim beneath a faucet handle that covers the faucet stem and the hole; the escutcheon is used for vanity purposes.

Expansion Tank:

A tank with thermal expansion that has the ability to absorb excess pressure.

[F]

Fall/Flow:

For the purpose of adequate drainage, the accurate slope of a pipe.

Female Fitting:

A fitting in which another fitting or pipe is inserted.

Finish Plumbing:

Plumbing fixture installation to make a system usable.

Fixture:

The device within a plumbing system that provides a supply of water and or its disposal.

Flapper Valve:

A piece of equipment on the bottom of the toilet tank that opens and closes, regulating the flow of water from the tank into the bowl.

Float Ball:

A ball connected to the ballcock that rises and falls with the water within the tank. It regulates the ballcock as needed.

Floor Flange:

A piece of equipment that connects a toilet and floor drain.

Flushometer:

A valve within a toilet that automatically shuts off after it reads a pre-set amount of water.

Flushometer Tank System:

A toilet flushing system that uses water pressure to flush instead of the traditional gravity flushing system.

Flux:

Flux is a paste that assists with the fusion of copper pipes and fittings before soldering. The paste helps the fusion and prevents oxidation.

Footprint:

The amount of floor space taken by an appliance.

French Drain:

A covered ditch with a layer of stones or other material.

[G]

Gas Cock:

A plug valve that is installed and used between a main gas line and an appliance.

Gas Control:

A piece of equipment that controls gas pressure on a water heater.

Gate:

A Gate manages the flow in a conduit, pipe, or tunnel.

Gate Diverter:

A lever on a tub that activates the diverter valve.

Gravity Operated Toilet:

A flushing system that uses the natural downward pressure of water in a tank to effectively flush the toilet.

Gray Water:

Gray water is waste from sinks, showers, and bathtubs.

[H]

Horizontal Branch:

Drain pipes that run laterally. They run from plumbing fixtures to waste stacks in a building or in the soil.

Horizontal Run:

The horizontal length between where the fluid enter a pipe and where it leaves.

Hose Bibb:

An outdoor faucet.

House Trap:

A u-shaped fitting that has two adjacent cleanout plugs.

Hubless (No-Hub):

A drainage pipe made of cast iron that utilizes neoprene gaskets and clamps.

Hydronic:

A system that transports heat through circulated water.

[I]

I.D.:

The abbreviation for inside diameter.

Indirect Wastes:

A waste pipe that discharges gray water by discharging it into a plumbing fixture.

Instantaneous Water Heater:

A water heater that uses a heat exchanger coil to heat the water.

[J]

Jet:

A toilet feature that directs water into the trapway to begin the siphon action.

Johnni-bolts:

A johnni-bolt or closet bolt is used to mount a toilet bowl to the closet flange.

[K]

Kafer Fitting:

A cast iron drainage pipe that attaches to the existing cast iron lines.

Knockout Plug:

PVC test plug.

[L]

Lavatory (Lav):

Another term for bathroom or restroom.

Leach Field:

For the purpose of emptying treated waste, a porous soil with septic tank lines running through it.

Leader:

A leader is a pipe that carries rainwater to the ground or sewer.

Lock Nut:

A nut that joins two pipes together.

[M]

Main:

All branches connect to this main water supply.

Male Threads:

The threads that are seen on the outside of pipes and fittings.

Malleable Fittings:

A pliable fitting made of metal.

Manifold:

A type of fitting that connects branches to the main.

Mechanicals:

The moving part components of plumbing, heating, and cooling systems in a building.

Multi-Stage Pump:

A pump with multiple impellers.

[N]

Nipple:

A short length of pipe that is installed between fittings.

No-Hub Connector:

Used to connect different materials together. It consists of a rubber sleeve and a stainless steel band with hose clamps.

[O]

O.D.:

Abbreviation for Outside Diameter.

O-Ring:

Used around valve stems, a rubber washer that creates a watertight seal.

Oakum:

Oakum woven hemp rope that has been treated with a waterproofing agent. It caulks bell and spigot pipe and fitting joints.

Outlet Sewer:

An outlet sewer is a pipe section that runs between a septic tank and drainage field in a septic system.

[P]

Packing:

A material used on faucets that prevents leaks.

Packing Nut:

A nut that keeps the faucet in position and holds the packing material.

PB (Polybutylene):

A type of flexible, plastic tubing used in some water supply systems.

Peak Hour Demand:

The peak hour demand is the time of day when hot water demand is at its climax.

pH:

pH is the amount of hydrogen ion concentration in water. The pH scale measures the alkalinity and acidity.

Pipe Dope:

A nickname for a material that is applied to a threaded fitting to create a watertight seal.

Pitch:

The slope of a drain pipe in the direction of the water flow.

Plumb:

The act of performing plumbing work.

Plumber's Putty:

Pliable putty that seals joints between drains and fixtures,

Plumbing Tree:

A set of drain waste, vent, and supply lines that have been pre-fabricated.

Plunger:

A rubber headed instrument that creates suction in a drain line or toilet and pushes a clog through the line.

Pop-Up Drain:

A type of drain assembly that uses lavatory lift rod or bath overflow plate lever. When it is lifted, the pop-up drain closes for the purpose of retaining water.

Port:

The opening in a burner head that allows gas or air-gas mixture to escape for ignition.

Positive Displacement Pump:

The PD pump makes a fluid motion by containing a fixed amount and moving it into the discharge pipe.

Pressure Balance Valve:

A shower mixing valve that maintains a balance between hot and cold water supplies by automatically regulating fluctuations in pressure. The result is constant temperature.

Pressure Tank:

A pressure tank is used in a well to pump water.

Pressure Tubing:

A pressure tube conducts fluids under pressure or at high temperatures.

PVC (Polyvinyl Chloride):

A PVC plastic pipe is used in non-pressure systems, such as drainage, waste, and vent systems.

[R]

Rated Storage Volume:

The amount of water within a tank.

Reamer:

A grinding tool that levels valve seats in faucets to improve the valve stem fit.

Recovery Capacity:

The amount of water in gallons/hour raised to 100 degrees at a given thermal efficiency,

Reducer:

A reducer connects different sized pipes together.

Return Circulation System:

A system that eliminates the waste of hot water for long runs; this system also adds storage.

Revent:

A pipe that connects with a vent system, used to vent a fixture trap.

Reverse Trap Water Closet:

A water closet that has a siphonic trapway at the back of the bowl.

Rigid Pipe:

A pipe that transmits the backfill load to the foundation beneath the pipe.

Rim Holes:

A number of holes circulated around the toilet rim. The incoming water flows into the bowl through the holes, washing the inner surface of the bowl.

Riser:

An assembly that connects a faucet and water supply stop valve. It is also a name of a supply line that goes from one story to the next.

Roof Flashing:

Installed to prevent leaks, it is a sheet metal at the break of a shingled roofline, sewer vents, and flue pipes.

Rough-In:

Installation into the proposed location of the drain, waste, vent, and supply lines.

Rough-In Dimensions:

The measured length between the center of a waste/supply opening or fixture to a wall or floor.

Run:

A section of pipe that extends from supply to fixture or drain to stack.

[S]

Saddle Valve:

A valve mounted on a pipe run near a clamping device or fitting. It enters the side of the pipe and provides a water supply for a low-demand device.

Sanitary Fitting:

A fitting that is designed to allow solid material to pass without clogging a drain, waste, and/or vent system.

Sanitary Sewer:

A drain that takes wastewater away from the house to a disposal system such as a sewer system or septic tank.

Self-Rimming Sink:

A sink with a built-in lip of the same material that supports the vanity top.

Service Entrance:

A pipe that connects the water company supply to the water meter.

Setting:

The distance from the top of the well to the top of the pump.

Shroud:

A drain outlet cover mounted below a wall-mount lavatory.

Siphon-Vortex Water Closet:

A type of toilet that has a trapway at the back of the bowl, integral flushing rim, and a water supply system that does not go into the trap.

Sleeve:

A pipe that runs through a wall to allow another pipe through it.

Slip Joint:

A connection made with compression fittings.

Soil Stack:

A main drain line that all branch lines connect to carry waste to the sewer.

Solder:

Melted metal alloy that fuses joints of metal together.

Spud:

A spud is a threaded opening on a water heater tank.

Stack:

A vertical main that reaches multiple stories; the main resides in the drain, waste, and vent system.

Stand Pipe:

A stand pipe is the name of several pipe types. A stand pipe is a vertical pipe that receives water from washing machines; a water supply for a fire sprinkler system, or a vertical pipe that has water pumped into it to produce a certain pressure.

Static Lift:

In a pump installation, the vertical length of space between the source and discharge water levels.

Stop Valve:

A valve beneath sinks and toilets that shuts off the water supply to one fixture without affecting the other.

Straight Cross:

A straight cross connects four pipes of the same diameter together.

Sump:

A pit for draining, collecting, or storing water.

Sweating:

Sweating has two definitions. It is slang for soldering and a term for condensation that builds outside of pipes or toilet tanks.

[T]

T & P (temperature and pressure) Valve:

A T&P valve is a piece of safety equipment that expels extra pressure or heat from within the tank.

Tailpiece:

A piece of pipe that is fitted between a fixture outlet and its trap.

Tail Pipe:

The tail pipe is added below the jet assembly in a well system.

Tank:

A tank is part of a toilet system. It is a reservoir for flush water. The tank houses the ballcock, flush valve, and trip lever as well.

Tank Cross:

A fitting installed between a well pump and a bladder tank with valve, gauge, and an outlet for a pressure-relief valve.

Tap Tee:

A tee made of cast iron; this tee has a threaded female inlet.

Tee:

A t-shaped fitting that has three openings for branch lines.

Thermocouple:

A thermocouple is a small electric generator.

Thermostatic Valve:

For showers, this valve balances pressure and temperature control.

Trap:

A curve in a drain line that traps sewer odors, preventing them from escaping into the atmosphere. All drains have "P" traps, but toilets, which have "S" traps.

Trap Arm:

In a drainage trap, the trap arm acts as a waste arm.

Trap Dip:

In a drainage trap, the trap dip is the u-bend.

Trap Primer:

A line that connects the cold water line to the drainage trap for the purpose of releasing small amounts of water into the trap to maintain the water seal.

Trap Seal:

A trap seal is the height of the water in a toilet bowl while not in use. It acts as a water seal to prevent sewer gases from seeping into the home.

Trapway:

A connection between the bowl and waste outlet in a toilet. Trapways are measured by the largest diameter ball that can pass through it.

Trip Lever:

The handle and actuating arm on a toilet tank or the lever that controls the drain on a bathtub.

[U]

Uni-flex:

A one-piece stop and riser.

Union:

A three piece fitting that joins two pipes together with the ability to disconnect without cutting the pipe.

Usable Storage:

The percentage of hot water that can be taken from a tank without lowering the temperature to the point it is not considered hot.

[V]

Vacuum Breaker:

A device that prevents the backflow of impure water into the water supply system.

Valve Seat:

A part of the valve that is stationary. Water flow halts when the moveable portion of the valve meets the valve seat.

Vent:

For the purpose of preventing siphoning, a pipe that brings air into the drain system to balance air pressure.

Vent Header:

Several vents connect to the vent header, which leads to the vent stack.

Vent Stack:

The top portion of a soil stack, that allows gases and odors to escape.

Vent System:

A vent system provides an airflow to and from the drainage system. The air protects against siphoning and back-pressure.

Venturi:

For the purpose of creating a suction in a vacuum pump, a venturi is a short, narrow tube that increases the speed of the flow of a fluid and decreases the fluid pressure.

Viscosity:

Viscosity is the resistance of fluid flow due to molecular friction.

Vitreous China:

A non-porous ceramic used for bathroom fixtures.

[W]

Washdown Water Closet:

A water closet with a front siphon trapway and integral flushing rim.

Waste Arm:

A waste arm is an extension pipe that extends from a fixture into the wall.

Waste & Overflow:

A waste and overflow is a drain assembly for a bathtub. It has an outlet at the top that removes any overflow of water and a drain at the bottom that removes wastewater.

Wet Vent:

A vent that also acts as a drain.

Widespread:

A type of bathroom faucet with separate spout and handles.

WYE:

For the purpose of making branch lines, a Y-shaped fitting with three openings.

[Y]

Yoke:

A casting with hot and cold valves and the mixing chamber for water.

Yoke Vent:

A yoke vent prevents pressure changes in the stacks by connecting upward from a soil or waste stack to the vent stack.

 

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