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Plumbing Glossary Common Plumbing Terms

Plumbing Glossary

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  • Components and Fixtures

    • Aerator: Insert that mixes air into flowing water to reduce splashing and is screwed onto a faucet
    • Ball Check Valve: Valve with a ball used to stop liquid flowing in one direction
    • Closet Bend: Curved fitting connecting toilet to the drain, located under toilet
    • Closet Flange: Often called a floor flange, ring used to connect to closet bend and anchor a toilet
    • Copper: A metal pipe and fitting used to create water systems
    • Fitting: A piece that connects two sections of pipe
    • Flow Control Valve: Device that can reduce water flow to plumbing fixtures while improving efficiency and reducing costs
    • Gasket: Ring made of fiber or flat rubber and used between metal fixtures to create a watertight seal
    • Interceptor: Device in drain systems used to separate oil and grease
    • Main: All branches connect to this main pipeline in a drain system or supply
    • Manifold: Multiple branches that connect to the main via a fitting and act as a distribution point
    • O-Ring: Makes valve stems watertight via a round rubber washer
    • Scald Guard: Valve that shifts back and forth behind shower handle when there are sudden pressure drops; keeps the pressure balance between hot and cold in your shower
    • Shutoff Valve: Value used for repairs to stop water supply and is generally under the toilet or sink
    • Tee: Used where three pipes cross and is a T-shaped fitting
    • Trap: Plumbing portion that is curved and made to hold enough water that will seal or block that piece of pipe from odors, pests, and gasses
    • Valve Seat: The section of a valve that is stationary
    • Vent: Section of drainpipe that is vertical or sloped and allows sewer gasses to escape while being replaced by outdoor air so pressure isn’t lost during venting
    • Water Hammer Arrestor: Device that absorbs hydraulic shock and helps prevent the water hammer banging sound that happens when water supply is suddenly cut to a fixture
    • Wye Fitting: Two sections of pipe are connected at a 45-degree angle with drain fitting

    General Plumbing Terms

    • Bleed: The act of opening a valve at the end of a pipe to release excess air
    • Branch Drain: The fixture drain which connects to the main drain pipeline
    • Brass: Generic term used to refer to a faucet or fixture
    • Effluent: Liquid waste that is found in a septic system
    • Flow Rate: Amount of water that flows through a plumbing system and can be measured in gallons per hour (GPH) or gallons per minute (GPM)
    • Gallons per Flush (GPF): The amount of regulated water needed to flush a toilet; the current maximum amount of GPF for new toilets is 1.6 GPF
    • Gray Water: Water waste produced from fixtures that are not toilets
    • KiloPascal (kPa): Unit of pressure in the metric system equaling 1/100th of an atmosphere
    • Maximum Containment Level (MCL): The maximum level of contaminants by law that is permitted in a water supply
    • Non-Ferrous: Does not contain iron
    • Potable: Water that has been deemed safe to consume
    • Pressure Head: The vertical pressure force that is caused by water at a depth of one foot; pressure in a plumbing system; unit of measure
    • Riser: Pipes that bring water to a fixture or higher floor from the branch and are vertical
    • Sediment: Debris that is often found near the bottom of water tanks
    • Soil Pipe: Pipe from a toilet that carries waste
    • Trap Seal: Water that acts as a liquid seal in a trap
    • Water Hammer: Hydraulic shock caused when the water supply is cut off suddenly and often produces a loud banging sound
    • Water Hammer Arrestor: Device that absorbs hydraulic shock and helps prevent the water hammer banging sound that happens when water supply is suddenly cut to a fixture

    Septic System Specific Components

    • Absorption Field: Seeping field, also known as a leach field, designed to disperse and filter liquid waste from a septic tank
    • Leach Line: Pipes from septic tank to absorption/leach field that carry liquid waste
    • Septic Tank: Tank that temporarily stores solid, liquid, and sludge waste; mainly used where sewer lines aren’t available like in rural settings; connected to absorption field where liquids drain

    Tools and Materials

    • ABS: Acrylonitrile Butadiene Styrene which is commonly found in drains, waste lines, and vents and is a black plastic pipe
    • Auger: Used to pull clogs from toilet traps and is a flexible rod with a curved end
    • Blowbag: Tools used for clogged drains made of a nozzle with rubber bladder attached; bladder swells to fill pipe and will release bursts of water to create a path through the barrier
    • CPVC: Black PVC pipe, frequently used in water supply systems, made from chlorinated polyvinyl-chloride and treated to endure high temperatures
    • Dope: Lubricant used for plumbing pipe threads
    • PEX: Polyethylene that is cross-linked and stronger than normal PE
    • Plumber’s Putty: Putty used to seal joints between metal pieces and fixture settings with a dough-like consistency
    • Plunger: Commonly used to unclog toilets and drains, this “plumber’s helper” is a 6-inch rubber suction cup that has a wood handle
    • Polybutylene (PB): Can be used for bathroom fixtures in some supply lines and is bendable tubing
    • Polyethylene (PE): Used in supply lines and are flexible pipes
    • PVC: White pipe used for waste or vent pipes or drains and made of rigid polyvinyl-chloride plastic
    • Snake: Used to dislodge clogs in a drain and is a flexible and thin cord of spiral-wound metal
    • Teflon Tape: Tape wrapped around threads of a pipe in order to create a tighter joint seal; made from fluorocarbon polymer with non-stick properties
  • HVAC/IAQ & Plumbing Glossaries

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