Plumbing Glossary | Hi-Desert Plumbing

Full Spectrum Glossary of Terms

We’ve put together this special guide to help you grasp the lingo of the plumbing world. Whether you’re a plumbing expert or just starting to explore the world of pipes and faucets, we’re here to ensure that plumbing jargon won’t leave you scratching your head.

Dive in and start decoding the language of pipes and drains with us!

  • Aerator: A device that is affixed to the extremity of a faucet spout and functions to regulate the flow of water while incorporating air to mitigate splashing. The efficiency of kitchen and lavatory plumbing is frequently enhanced by its use.

    Angle Stop Valve: A shut-off valve that operates by turning a handle or knob. Commonly used in kitchen and bathroom plumbing, usually beneath sinks to control the flow of water to fixtures.

    Anode Rod: The tank of a water heater is protected from corrosion by a sacrificial rod, which aids in the tank’s longevity.

    Anti-Siphon: A device that prevents undesirable water sources from being siphoned back into the potable water supply. Essential in commercial plumbing to maintain water purity.

    ABS (Acrylonitrile Butadiene Styrene): A type of plastic piping used primarily for venting, waste, and drain lines in residential and commercial plumbing.

    Adapter Fitting: A fitting that joins pipes made of different materials or sizes.

    Access Panel: A door, panel, or piece of plywood that can be easily removed to provide access to a shut-off valve, drain clean-out, or other type of plumbing fixture.

    Automatic Drip Systems: Systems used primarily in commercial plumbing that allows controlled, consistent delivery of water to specific locations.

  • Backflow: A reversal of the normal direction of water flow in a water-based system, often necessitating immediate emergency plumbing interventions.

    Ball Valve: A valve that utilizes a ball to seal as opposed a seat to stop flow in a pipeline. Often used in water line repairs and maintenance.

    Booster Pumps: Mechanical devices used to increase fluid pressure, ensuring consistent water flow, especially in multi-story commercial buildings.

    Braided Supply Line: A flexible water supply line, commonly used in kitchen and bathroom plumbing fixtures.

    Branch Vent: A vent connecting one or more individual vents with a vent stack or stack vent.

    Building Drain: The lowest part of a drainage system that receives discharge from soil, waste, and other drainage pipes inside a building and runs to an external point of disposal.

    Burst Pipe: A pipe that has ruptured, often due to freezing or physical damage, often necessitating immediate emergency plumbing.

    Bathroom Plumbing: Refers to all the plumbing activities associated with bathroom fixtures, including toilets, showers, bathtubs, and sinks.

  • Cleanout: An opening providing access to a drain or sewer pipe for the removal of blockages, essential for drain cleaning.

    Closet Auger: A tool used to clear blockages from toilets.

    Commercial Plumbing: Plumbing services tailored to businesses, industries, or large residential complexes.

    Compression Fitting: A type of fitting used with copper or plastic tubing, tightened down with a compression nut, securing the tubing in place.

    Curb Cock: A valve located in the water service pipe near the curb and between the main and the building. Used for turning on or shutting off water to a premise.

    Curb Stop: The point where the water service pipe meets the main, used for controlling water supply.

    Cutoff Valve: A valve that allows water supply to be turned off to one fixture without affecting the water supply to other fixtures.

    Copper Piping: A durable, corrosion-resistant type of piping used for water lines and often employed in repiping services.

  • Drain Cleaning: The process of ensuring that waste water flows out freely from drains, often involving the removal of blockages.

    Dielectric Union: A fitting that separates two metals (e.g., copper and galvanized steel) to prevent corrosion.

    Direct Vent: A pipe that safely expels gases from appliances to the outdoors.

    Diverter: A valve in the spout or faucet that diverts water from the bathtub faucet to the showerhead.

    DWV (Drain, Waste, Vent): Refers to the sections of a plumbing system that remove wastewater from fixtures and vent the system.

    Drip Leg: A small pipe or tee located at a low point in the gas piping to gather condensate and allow its removal.

    Drain Trap: A curved section of drain line that stops sewer odors from escaping into the living space.

    Drain Vent: A pipe that allows the entry or exit of air in a drainage system to protect trap seals from siphonage and back pressure.

  • Emergency Plumbing: Immediate plumbing services provided in situations that pose risks to property or health.

    Expansion Tank: A tank that absorbs excess pressure due to thermal expansion in a closed water heating system.

    Escutcheon: Decorative plate used to cover a hole in a wall or floor around a plumbing fixture.

    Elbow: A pipe fitting that connects two lengths of pipe at an angle.

    Effluent: Liquid waste or sewage discharged from a treatment plant or septic system.

    Endurance Test: A procedure to check the longevity and performance of plumbing fixtures or systems.

    Equalization Basin: A large holding chamber used to balance out large flow variations in wastewater treatment.

    Emergency Shut-off Valve: A valve, often hand-operated, used to shut off the water supply in case of emergencies or repairs.

  • Flapper Valve: The part in the toilet tank that regulates the flow of water to the bowl during a flush.

    Float Ball: The floating ball attached to the ballcock inside the tank that rises or falls (depending) with changing water levels in the tank, and activates or shuts off the ballcock as needed.

    Flood Level (FL): The highest point in a sink, lavatory, or tub to which water can rise before it overflows.

    Fixture Unit: A standardized measure representing the load-producing effects on a plumbing system from different types of fixtures.

    Flow Control Valve: A device designed to regulate the flow of water or other fluids.

    Frost-proof Hose Bibb: An outdoor faucet that prevents water from freezing inside the spigot.

    Full-port Valve: A type of ball valve where the bore inside the valve is the same size as the pipe. This design results in no loss of pressure or flow.

    Flux: A substance used in soldering and brazing to help ensure a clean joint.

  • Gas Lines: Piping systems that transport natural gas from the main source to appliances in a property.

    Grease Trap: A device that captures grease and solid waste before it enters a wastewater disposal system.

    Gasket: A flat (usually rubber) seal that ensures a watertight joint between two surfaces.

    Gate Valve: A valve that utilizes a gate or wedge to stop or allow flow in a pipeline.

    GPM (Gallons Per Minute): A measurement indicating the flow rate of water.

    Gravity Operated Toilet: A toilet that counts on the force of gravity to flush.

    Ground Joint: A joint containing a gasket or washer to ensure a watertight seal.

    Galvanized Pipe: Steel or iron pipes that have been coated with zinc for increased resistance to corrosion.

  • Heat Exchanger: A device that transfers heat from one fluid to another without mixing them.

    Hose Bibb: An outdoor faucet, used for connecting a hose.

    Horizontal Branch: Lateral drain pipes that go from plumbing fixtures to the waste stack within a building or in the soil are referred to as horizontal branches.

    Hydro Jetting: A method of cleaning sewers and drains using high-pressure water streams.

    Hydronic: Pertaining to a heating or cooling system that uses water or steam as the medium.

    Hydrostatic Pressure: The pressure exerted by a fluid due to its weight.

    Hard Water: Water with a high mineral content, usually calcium and magnesium, which can cause scaling in water heaters and pipes.

    Hammer Arrestor: A device that absorbs sudden pressure changes in the water supply system, preventing water hammer.

  • Inlet Valve: The valve in a toilet that allows the refill of the tank after a flush.

    Interceptor: A device designed to separate and retain deleterious, hazardous, or undesirable matter from normal wastes.

    Indirect Waste Pipe: A waste pipe that does not connect directly with the drainage system but conveys liquid wastes by discharging into a receptor connected to the drainage system.

    Isolation Valve: A valve that isolates a portion of a system to allow maintenance without shutting down the entire system.

    Insulation Jacket: A protective cover around a water heater to reduce heat loss.

    Invert: The lowest point of the inside of any pipe or conduit that is not vertical.

    Irrigation System: Systems designed to deliver water to landscapes or agricultural lands.

    Intake: The pipe through which water is drawn from a main source.

  • J-Bend: The section of a drain trap that is shaped like the letter “J”, where water remains to provide a water seal.

    Joint Compound: A material applied to thread joints to ensure a leak-proof seal.

    Jetting: A method of clearing blockages from pipes using high-pressure water streams, similar to hydro jetting.

    Jumper Wire: A wire or strap used to ensure electrical continuity across a joint.

    Joint Runner: A tool used in lead jointing to smooth the joint and ensure a complete seal.

    Jack Faucet: A specialized faucet, typically found in laboratories, which allows the user to regulate the flow of gases or vacuum.

    Junction Box: A box in which the joins of electrical wires or plumbing pipes are made.

    Jet Pump: A type of pump, often used in well pump repairs, that uses an impeller and a venturi to draw water from a well.

  • Kitchen Plumbing: Pertaining to the installation, maintenance, and repair of plumbing fixtures and systems in a kitchen, including sinks, dishwashers, and water lines.

    Knockout Plug: A temporary plug in a floor drain or a fixture drain to prevent sewer gas from escaping during construction.

    Kitec Piping: A type of flexible plumbing pipe, commonly used for water supply lines but has faced recalls due to durability issues.

    Kilopascal (kPa): A unit of pressure measurement. In plumbing, it’s commonly used to describe water or gas pressure.

    Kinetic Water Ram: A tool used to clear blockages from pipes, using a burst of compressed air.

    Kitchenette: A small kitchen or an area with kitchen facilities, often found in studio apartments or office settings.

    Kettle Tap: A type of faucet that delivers near boiling water on demand, often used in kitchens.

    Knockout Seal: A circular piece of metal used to cover a hole in an electrical box or a plumbing fixture.

  • Lavatory: Another term for a bathroom sink.

    Lead-free Pipes: Piping systems made without lead, ensuring safer drinking water.

    Low-Flow Fixture: Plumbing fixtures designed to use less water than traditional fixtures.

    Lateral Line: The wastewater pipe that connects individual properties to the main sewer line.

    Line Pressure: The pressure in a water supply system.

    Leak Detection: The process of identifying and locating water leaks in a plumbing system, utilizing specialized equipment.

    Lime Scale: A hard, chalky deposit often found in pipes and appliances due to hard water.

    Lip Seal: A type of seal commonly found in plumbing fixtures to prevent leaks.

  • Main: The primary artery of supply in the water supply or drain system.

    Manifold: A fitting that connects a number of branches to the main; serves as a distribution point.

    Mechanical Joint: A connection between pipes, made by physically fitting them together.

    Mixer Tap: A tap that combines hot and cold water supply, allowing water of desired temperature to come out of a single spout.

    Municipal Water System: A city or regional service that provides potable water to homes and businesses.

    Meter Cock: A valve placed on the water supply line, usually close to the meter.

    Mini-Vent: A type of air admittance valve used to vent a fixture trap.

    Main Vent: The principal artery of the venting system to which vent branches may be connected.

  • No-Hub Connector: Connector for no-hub iron pipe that consists of a rubber sleeve and a stainless steel band that is fastened by hose clamps. This connector is referred to as a “no-hub connector.”

    Nipple: A short length of pipe installed between couplings or other fittings.

    Neutralizer: A device or substance that brings pH levels to a neutral state, commonly used in water filtration systems.

    Non-Potable: Water that is not safe for human consumption.

    Needle Valve: A type of valve with a small port and a threaded, needle-shaped plunger.

    Natural Gas Line: Piping systems specifically designed to transport natural gas.

    Non-return Valve: Another term for a check valve; it ensures fluid flows in only one direction.

    NPT (National Pipe Thread): A U.S. standard for tapered threads used on threaded pipes and fittings.

  • O-Ring: A gasket in the shape of a ring, typically made of elastic materials, used to seal connections in pipes and fittings.

    Overflow: A system that allows excess water to flow out, commonly seen in bathtubs and sinks to prevent flooding.

    Odor Trap: A U-shaped pipe or a similar structure that holds water, blocking sewer gases from escaping into a building.

    Open System: A heating system where the water in the heating pipes is directly connected to the main water supply.

    Offset: A combination of elbows or bends that brings one section of pipe out of line but into a line parallel with another section.

    Outflow Pipe: The pipe through which water is discharged from a main source or system.

    Oxidation Reduction Potential (ORP): A measure used in water treatment to indicate the oxidizing or reducing potential of a water sample.

    Orifice: A small opening or hole in a body; in plumbing, it often refers to openings in fixtures or piping where water can flow through.

  • Potable Water: Water that is safe and fit for consumption.

    Pressure Reducing Valve (PRV): A valve that automatically cuts off the flow of a liquid or gas at a certain pressure.

    Pipe Wrench: A type of wrench used for turning pipes and fittings made of metal.

    Pop-up Drain: A type of drain often found in bathroom sinks; it has a mechanism to open or close the drain plug.

    P-Trap: A U-shaped pipe beneath fixtures such as sinks. It retains a small amount of water, preventing sewer gases from entering a home.

    Pipe Dope: A slang term for pipe joint compound; used to seal and lubricate threaded pipe joints.

    Pot Filler: A faucet mounted on the wall behind a stove, used to fill pots with water.

    Pressure Relief Valve: A safety valve that opens to release excess pressure, commonly found on water heaters.

  • Quarter-Turn Valve: A valve that requires only a quarter turn to open or close.

    Quick Connect Fitting: A fitting that allows for easy and quick connection or disconnection, without the need for tools.

    Quill: The extended lip or spout on an overflow or other drain.

    Quiet Fill Valve: A type of toilet fill valve designed to refill the tank quietly.

    Quality Check Valve: A high-quality valve that ensures fluid flows in only one direction, preventing backflow.

    Quick-Set Compound: A fast-drying substance used for sealing joints.

    Quadratic Flow Control: A sophisticated flow control mechanism that ensures consistent flow rates.

    Quarry Tile: A hard-fired tile traditionally used in commercial kitchens and areas that require a slip-resistant surface.

  • Repiping: The process of replacing old or damaged pipes in a building.

    Riser: A vertical water supply pipe, especially one that supplies a fire sprinkler system.

    Reducer: A fitting that connects pipes of different diameters.

    Roof Vent: A pipe that allows gas from the home’s plumbing system to vent outside.

    Rough-In: The initial phase of a plumbing project, where pipes are laid out and connected, but fixtures are not yet installed.

    Return Line: A pipe that returns water from a heating or cooling system to the main unit.

    Rooter Machine: A machine used to remove tree roots and other obstructions from sewer lines.

    RPZ (Reduced Pressure Zone): A type of backflow preventer that uses a differential pressure principle to protect water supplies from contamination.

  • Sewer Line Repair: The process of fixing damaged or clogged sewer lines.

    Shutoff Valve: A valve that allows you to turn off the supply of water to a particular fixture.

    Saddle Valve: A valve mounted on a pipe, used to make a quick connection.

    Septic System: An independent sewage treatment system, usually for homes in rural areas.

    Slip Joint: A type of connection that allows two pipes to be joined by simply pushing one inside the other.

    Solder: A fusible alloy used to create a permanent bond between metal pieces.

    Sovent System: A patented single-stack drainage system with engineered internal fittings.

    Soft Water: Water that has been treated to remove most of its minerals, often using a water softener.

  • Trap: A bend in a pipe that retains a small amount of water, preventing sewer gases from entering a home.

    Tailpiece: The section of pipe between a fixture and its trap.

    Thread Seal Tape: A Teflon tape used to seal threaded pipe joints, preventing leaks.

    Thermostatic Mixing Valve: A valve that automatically mixes hot and cold water to ensure a constant, safe temperature.

    Tankless Water Heater: A water heater that heats water on demand, without a storage tank.

    Tubing Cutter: A tool used to cut copper or plastic tubing.

    T&P Valve (Temperature and Pressure Relief Valve): A safety device on a water heater that releases pressure and prevents potential explosions.

    Toilet Flapper: A rubber component in a toilet tank that opens to allow water into the bowl and seals the tank to refill.

  • Union: A fitting that connects two sections of pipe and allows for their disconnection without cutting.

    U-bend: Another term for the P-trap; a section of pipe shaped like a “U” that traps water, creating a barrier against sewer gas.

    Upfeed System: A water supply system in which water is pumped or lifted to a storage tank above the fixtures and then flows by gravity to the fixtures.

    Underground Plumbing: Refers to plumbing systems and installations that are buried beneath the ground, often including main sewer and water supply lines.

    Undermount Sink: A type of sink that is mounted beneath a countertop, providing a smooth surface from the counter into the sink.

    Universal Rundle: A brand known for its plumbing fixtures.

    Ultraviolet (UV) Filtration: A water treatment method that uses UV light to kill or render harmless microorganisms in water.

    Utility Sink: A large, deep sink used for laundry and other household tasks.

  • Vent Stack: The main vertical vent in a building’s drain system.

    Valve Seat: The non-moving part of a valve against which the moving part seals or closes.

    Vacuum Breaker: A device that prevents unwanted back-siphonage of contaminated water into a potable water system.

    Vitreous China: A material used for many plumbing fixtures like toilets and sinks. It’s glossy and easy to clean.

    Vent System: A system of pipes and fittings that allow gases to escape and air to enter, ensuring smooth flow of wastewater.

    Vortex Flow Meter: A device used to measure the flow rate of fluids by creating a vortex in the fluid flow.

    Valve Box: An accessible enclosure in which a valve or set of valves is contained.

    Volume Control Valve: A valve used in showers to control the volume or flow rate of water.

  • Water Line Repair: The process of fixing damaged or malfunctioning water supply lines.

    Water Hammer: A loud noise in a water pipe caused by an abrupt stoppage of flow.

    Water Closet: Another term for a toilet.

    Wet Vent: A plumbing term for a vent that also carries liquid waste.

    Wall-Hung Toilet: A type of toilet where the bowl is attached to the wall and the tank is concealed behind it.

    Water Softener: A device or substance used to reduce the hardness of water.

    Wye Fitting: A Y-shaped fitting used to connect three sections of pipe.

    Washer: A flat ring of rubber or plastic, used to prevent leaks in faucets and other fittings.

  • (Note: “X” is an uncommon letter in the plumbing industry. Some entries might be tangentially related.)

    Xeriscaping: Landscaping and gardening in ways that reduce or eliminate the need for supplemental water from irrigation. Often interacts with plumbing in the context of water conservation.

    X-Pipe: A type of pipe fitting used primarily in exhaust systems but can refer to any piping structure that resembles the letter “X”.

    XH (Extra Heavy): A classification for pipes indicating extra thick walls.

    XP: An abbreviation often seen in plumbing plans indicating the location of a water supply point.

    Cross-Connection: A connection or structural arrangement in a plumbing system where it’s possible for a non-potable substance to come into contact with a potable water supply.

    Cross-Linking: A process used in the production of PEX (cross-linked polyethylene) pipes.

  • Yard Hydrant: An outdoor water faucet that can be used to provide water to areas away from the building.

    Y-Strainer: A device used in pipelines to filter debris from the flow and protect pumps and other equipment.

    Yellow Brass: A type of brass with a higher percentage of zinc, commonly used in making plumbing fixtures.

    Yoke: A fitting that connects two parts together, often seen in faucet assemblies.

    Y-Branch: A Y-shaped fitting used to connect three sections of pipe.

  • Zone Valve: A device used in heating systems to control the flow of water or steam to different zones.

    Zero Radius Sink: A type of sink characterized by its sharp, 90-degree corners.

    Zinc-coated Pipes: Pipes that have been coated with zinc to prevent rusting and corrosion.

    Zonal Heating: A heating system where specific areas or zones can be temperature-controlled independently of others.