Plumbing Glossary of Terms

What's a dip tube? Is a flapper a girl who liked to dance in the 1920's? How does a damper work? We can help you with many of the technical terms that come along with the plumbing, heating and cooling industry.

Absorption Field

A leeching or seeping field engineered to receive septic tank effluent. .

Acidity

The level of concentration of acid in water. Acid will neutralize an alkali or base. It is usually expressed in terms of its calcium carbonate equivalent. .

Acrylic

Thermoplastic used on surface of bathtubs and whirlpools. Usually comes in sheets and backed by fiberglass to form shower walls. .

Aerator

A device screwed into the end of a faucet spout that mixes air into flowing water, and controls flow to reduce splashing. It sometimes contains a baffle to reduce flow to 2.5 gpm.

Air Gap

A device mounted at the back of a kitchen sink, connecting to the drain line between a dishwasher and disposer to allow the dishwasher to discharge freely into the disposer while preventing contaminated water from siphoning back into the dishwasher. Can be any unobstructed vertical opening between the lowest opening of a waste line and the flood level of the device into which it empties to relieve pressure and prevent backflow contamination.

Air Volume Control

Maintains the air charge in a standard water storage tank. Pre-charged tanks do not require an air volume control. .

Alkalinity

The measurement of constituents in a water supply which determine alkaline conditions. The alkalinity of water is a measure of its capacity to neutralize acids See pH.

Angle Stop

A shutoff valve between the water pipes and a faucet. Its inlet connects to the water supply pipe in a wall, and its outlet angles up 90 degrees toward the faucet. These are usually used to shut off water to a fixture in case of an emergency repair rather than daily usage.

Anode Rod

A sacrificial rod installed in a water heater, composed of one or more metals that protects the tank from corrosion, helping to extend the life of the tank. .

Aquifer

A layer or zone below the surface of the earth which is capable of yielding a significant volume of water. The upper level of the aquifer is called the water table.

Back Flow Preventer

A device to prevent backflow, esp. into a potable water supply. This is generally required for sprinkler systems, handheld showers, pullout faucet spouts, kitchen sprayers, etc.

Back Flow

The circumstance of water traveling from one system back into any part of the main distribution system, usually by siphoning. .

Backwater Valve

Sewer line valve that prevents sewage from flowing back into the house .

Baffle

An object placed in an appliance to change the direction of, or retard the flow of air, air-gas mixtures, or flue gases.

Ballcock

The fill valve that controls the flow of water from the water supply line into a gravity-operated toilet tank. It is controlled by a float mechanism that floats in the tank water. When the toilet is flushed, the float drops and opens the ballcock, releasing water into the tank and/or bowl. As the water in the tank is restored, the float rises and shuts off the ballcock when the tank is full.

Barrier-Free

Relating to handicap access, e.g. a shower enclosure system having minimal or no bottom track and openings that are wheelchair-accessible. .

Bleed

To drain a pipe of excess air by opening a valve at the end of the pipe .

Brine

A strong solution of sodium chloride (salt) used in the regeneration of ion exchange water softeners.

Carbon Dioxide

A gas present in the atmosphere, formed by the decay of organic matter; the gas in carbonated beverages; dissolved in water it forms carbonic acid.

Casing

A tubular structure intended to be watertight installed in the excavated or drilled hole to maintain the well opening and to prevent ground water from entering the well.

Catch Basin

Large underground container, with a grate on the top, for collection of storm water run-off. It catches or collects dirt and other debris and prevents them from polluting streams and lakes..

Cockhole Cover

A round cover-plate or disk installed on a sink to cover an unused faucet hole. .

Coliform Bacteria

Non-pathogenic microorganisms used in testing water to indicate the presence of pathogenic bacteria.

Composite

Composite sinks made from high-tech, high-strength, color- impregnated that resists shipping and scratching. .

Corrosive Water

A water condition of low pH (acid condition) that can corrode metal pipes, pool fixtures and pumps. (Unbalanced water).

Cross-connection

Any connection or situation that may allow wastewater to enter the supply system. .

Deck Mount

Describes a faucet that is mounted on the deck of the bathtub enclosure, rather than on the rim of the bathtub or on the wall. Also referred to as a Roman spout faucet. Also known as a sunken tub, the deck-mount tub is usually mounted on a platform and has no apron or decorative side.

Degree Rise

Difference between the starting water temperature and the ending temperature after heating is complete. .

Dip Tube

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

Diverter

Valves which direct water to various outlets. They are used in showers, tubs, bidets, and sinks.

Domestic Hot Water

Water heated for residential washing, bathing, etc. .

Double Threshold

A shower base used in a corner application where one threshold is used as an entrance and the other has a glass wall.

Drawdown

The distance the water level drops below the standing water level while the pump is operating. .

Drum Trap

An obsolete, non-vented drain lead or cast iron canister trap formerly used in sewer lines. .

Dual Element Heater

An electric water heater with an upper and lower element for heating water. .

E. Coli

The common abbreviation of Escherichia Coli. One of the members of the coliform groups of bacteria indicating fecal contamination.

Effluent

Septic system liquid waste .

Ejector

A mechanical device for pumping sewage from below the sewer line.

Electrolysis

A process involving chemical change caused by the passage of an electric current through a liquid.

Escutcheon

A decorative metal flange or trim shield beneath a faucet handle that covers the faucet stem and the hole in the fixture or wall.

Expansion Tank

A tank designed to absorb excess pressure due to thermal expansion. (e.g. closed system) .

Fecal Coliform

The portion of the coliform bacteria group which is present in the intestinal tracts and feces of warm-blooded animals. A common pollutant in water.

Fiberglass

Glass in a fibrous form used in the making of products such as shower stalls. .

Flapper

Flush ball; the moving part of the flush valve that seals the water into the tank or allows water to exit the tank for the flush cycle. The most common replacement part used on conventional toilets.

Float Ball

The floating ball connected to the ballcock inside the tank that rises or falls with changing water levels in the tank, and actuates or shuts off the ballcock as needed. .

Friction Loss

The loss of pressure caused by the turbulence created in water while traveling through the pipe. .

Grease Trap

A device that captures grease entering a system before it reaches the sewer lines. Usually used in commercial applications such as restaurants or cafeterias.

Ground Water

Naturally occurring water rising from the water table of the surrounding land. .

Hardness

The amount of dissolved minerals in water measured in grains per gallon (GPG). The most common minerals are calcium and magnesium.

Hose Bibb

An outdoor faucet, also used to supply washing machines. .

Integral Stops

Stops that allow the owner to shut off water supply at the faucet for maintenance without shutting off the water supply to the entire house.

Integral Vacuum Breaker

A device typically used in a sink or shower sprayer to keep water from backflowing into the fresh water supply. .

Interceptor

Device for separating grease and oil from drainage system. See grease trap. .

Limit stop

Faucet control unit used to adjust maximum water temperature .

Magnesium

One of the elements in the earth's crust, the compounds of which when dissolved in water make the water hard. The presence of magnesium in water is a factor contributing to the formation of scale and insoluble soap curds.

Manhole

Access opening to a hole, usually with a cover, through which a person may enter a sewer, boiler, drain, etc. (usually round to prevent the cover from falling into the opening).

Municipal Water

Water supplied by a city for public use; tap water. Usually held in a reservoir .

Natural Gas

A colorless, odorless fuel derived from the earth, consisting primarily of Methane (CH4). Odors are added to aid in leak detection.

Neo Angle Base

A shower base designed to allow the shower to fit into a corner using minimal floor space while maintaining an elegant look .

Nonpotable

Not suitable for drinking .

Overflow Tube

The vertical tube inside a toilet tank that directs water into the bowl in case the ballcock malfunctions. It is usually part of the flush valve. It prevents potential water damage caused by a tank overflow. A "constant-running" condition alerts the user to a problem. On most toilets, the overflow tube also has a refill tube flowing into it, which directs water from the ballcock through the overflow tube to the bowl, after a siphon break.

PHCC

Plumbing Heating Cooling Contractors Association .

PPM

Parts per million. A unit of measure for impurities in water.

Pilot

A small burner used to ignite the main burner .

Point of Use

Small water heater used for remote locations.

Power Venting

Mechanical draft exhaust to outside, usually utilizing room air to support combustion.

Pre-Charged Tank

A water storage tank pre-charged with air at factory featuring a vinyl bag to separate water from air which prevents waterlogging. This tank design provides greater drawdown than standard tanks. Pre-charged tanks do not require air volume control.

Pressure Balance Valve

Shower mixing valve that automatically maintains balance between incoming hot and cold water supplies by immediately regulating fluctuations in pressure. As a result, temperature remains constant, though the outlet pressure may drop. Also known as an anti-scald valve.

Pressure Reducing Valve

A valve that automatically reduces inlet water pressure to a specified value at its outlet under static cold water conditions. .

Pressure Regulator

A device for controlling and maintaining a uniform outlet gas pressure. .

Pressure Tank

Device used to pump water from a well .

Pumping Level

The lowest water level reached during pumping operation.

Recovery

The amount of water in gallons that can be heated in one hour. (gph).

Reverse Osmosis

A water treatment method whereby water is forced through a semi permeable membrane which filters out impurities.

Roof Flashing

Sheet metal installed at any break in a shingled roofline to prevent leaks. Also around sewer vents, fluepipes. .

Sanitary Sewer

House drain that carries wastewater away from the house to a sewer system or septic tank. .

Sealed Combustion

Sealing of combustion chamber to prevent spillage of combustion products. .

Sewer Gas

Gases, esp. methane, which may be combustible and poisonous from the decay of organic materials in the sewer system.

Sillcock

Outside faucet for hoses.

Sleeve

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

Soft Water

Water that has a low calcium and magnesium content.

Spark Ignition

Intermittent ignition devices that utilizes a spark to light a flame.

Static Water Level

The undisturbed level of water in the well before pumping.

Stud Guard

Short band of metal attached to wall studs to prevent nails from penetrating and damaging pipes.

Sulfate

A chemical compound that can cause laxative effects and give off a medicinal taste in concentrations around 30 gpg. In high concentration with high calcium hardness, it forms a white insoluble compound that is difficult to remove.

Sulfur

A yellowish solid element. The term also commonly describes to water containing hydrogen sulfide gas. The presence of Sulfur is marked by a smell like rotten eggs. .

Sump

A pit or pool for draining, collecting, or storing water. A chamber which provides water to the pump .

Temperature Rise

The number of degrees Fahrenheit that incoming water must be raised to reach the desired water temperature.

Tempering Valve

A in-line hot/cold mixing valve .

Thermocouple

Small electric generator. Electron flow between the hot junction of 1200 degrees F and cold junction of 600 degrees F creates millivoltage.

Thermopile

Apparatus that consists of a number of thermocouples combined so as to multiply the effect and is used for generating electrical current. .

Thermostat (Lower)

Device which automatically maintains a predetermined temperature in an appliance. .

Thermostat (Upper)

Device which automatically maintains a predetermined temperature in an appliance, usually equipped with a safety shutoff.

Thermostatic Valve

Pressure-balancing shower mixing valve with automatic temperature control. When temperature or pressure fluctuations occur at the water inlets, a thermal actuator adjusts the hot and cold ratio to maintain the original temperature setting.

Total Dissolved Solids

A measure of the total amount of dissolved matter in water .

Trap

Curved section of drain line that prevents sewer odors from escaping into the atmosphere. All fixtures that have drains must have a "P" trap installed. A toilet is the only plumbing fixture with an "S" trap.

Trip Lever

Flush handle and actuating arm on a toilet tank. Also the lever that opens and closes the drain on the bathtub waste and overflow. .

Vent

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

Water Hammer

A loud banging noise caused by the hydraulic shock of suddenly shutting off a water supply, where water moves against the side of containing pipe or vessel.

Water Hammer Arrestor

A device installed near a fixture to absorb the hydraulic shock caused by a sudden shutoff of water. .

Water Table

Level below the earth's surface at which the ground becomes saturated with water. .

Well Casing

A steel or plastic pipe inserted into a drilled well to prevent dirt and debris from contaminating the water.

Zeolite

A group of hydrated sodium aluminosilicates, either natural or synthetic, with ion exchange properties.

Zone of Aeration

The layer in the ground above the water table where the available voids are filled with air. Water falling on the ground percolates through this zone on its way to the aquifer.

Zone of Saturation

The layer in the ground in which all of the available voids are filled with water. .