| abbrev |
define |
| ABS | Acrylonitrile-Butadiene-Styrene. Rigid black plastic pipe used for drain / waste / vent lines. |
| A Valve | A manual gas shut-off valve. |
| AC | Alternating Current. Electrical supply in which the polarity of the wire reverses rapidly. |
| AGA | American Gas Association |
| AIA | American Institute of Architects |
| ANSI | American National Standards Act |
| API | American Petroleum Institute |
| ASA | American Supply Association |
| ASME | American Society of Mechanical Engineers |
| ASHRAE | American Society of Heating, Refrigeration, Air Conditioning Engineers. |
| ASSE | American Society of Sanitation Engineers |
| ASTM | American Society for Testing Materials |
| AWWA | American Water Works Association |
| Absolute Pressure | Atmospheric pressure added to gauge pressure. |
| Absorption Field | A leeching or seeping field engineered to receive septic tank effluent. |
| Acceptance Factor | Bladder tank draw-down expressed as a percentage. |
| Access Panel | A covered opening that allows access to service a plumbing system. |
| Acrylic | Thermo-plastic used on surface of shower walls / bathtubs / whirlpools. |
| Adaptor | A fitting that joins two different types of pipe together, or joins threaded to non-threaded pipe ends. |
| Adjusting Link | An adjustable strap / bar that forms a connection between the lift rod of a faucet and the ball lever assembly of the drain. |
| Aeration | The turbulent mixing of water and air to dissipate pollutants into the air |
| Aerator | A device attached to the end of a faucet that mixes air into flowing water.. |
| Air Admittance Valve | A device that replaces a traditional vent to allow air to enter the pipe and equalize pressure, preserving the seal of water in the fixture trap. |
| Air Chamber | A vertical, air-filled pipe or spring coil, set above the water line to absorb pressure when water is turned off at the faucet. |
| Air Check | A device that allows water, but not air, to pass through it. An air check is a typical component in treatment systems using a regenerant eductor. |
| Air Elimination Vent | A device which automatically eliminates trapped air in the ”closed-loop” hydronic system |
| 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. |
| Air-Gas Ratio | Ratio of combustion air supply flow rate to the fuel gas supply flow rate. |
| Air Lock | Blockage liquid flow of liquid (i.e. on suction side of pump) caused by an air bubble in the line. |
| Air Volume Control | Maintains the air charge in a standard water storage tank. Pre-charged tanks do not require an air volume control. |
| Alarm Check Valve | A check valve located in the riser of a wet pipe fire sprinkler system that sounds an alarm when water begins to pass through it. |
| Anaerobic | The ability to live and grow without air or free oxygen (i.e. some forms of bacteria that break down waste in a septic system.) |
| Angle Discharge Tube | A discharge tube that changes direction of the flow by 90°. |
| Angle Seat Wrench | A valve seat wrench with a handle that includes a 90° bend. |
| Angle Stop | A shutoff valve between water pipes and a faucet. The inlet connects to the water-supply pipe in a wall, the outlet angles up 90° to the faucet |
| Anode Rod | A sacrificial rod installed in a water heater. It is composed of one or more metals that protect the tank from corrosion and extend tank life. |
| Anti-Clog Suction | Whirlpool water recirculating system mechanism that prevents clogging but doesn’t restrict water flow. |
| Anti-Scald Valve | A 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 called pressure-balanced valve. |
| Anti-Siphon | Preventive device for back-flow of liquid such as on sprinkler systems to prevent water from trickling back into the feed supply. |
| API Specifications | American Petroleum Institute specifications |
| Apron | The apron (or skirting) is a decorative portion of a bathtub covering the rough-in area from the floor to the top rim of the tub. |
| Aquastat | A thermostat that is submerged in water. It is used to control operation of a specific device. |
| Aspiration | The process of mixing air with discharging water to enhance the hydro-massage effect of a whirlpool. |
| Auto Pilot | A gas pilot device that automatically shuts off gas supply to the appliance burner if the pilot flame is extinguished. |
| BC | Brushed Chrome finish used on faucets. |
| BHP | Brake Horse Power. The actual amount of horsepower consumed by a pump as measured on a dynamometer. |
| BN | Brushed Nickel finish used on faucets. |
| BTU | British Thermal Unit – A unit of heat energy required to raise the temperature of 1 lb. of water 1 degree Fahrenheit. |
| Backfire | Flashback of flame through the burner venturi causing the gas to burn at the orifice. |
| Back Flow | The act of water traveling from one system back into any part of the main distribution system (usually by siphoning. ) |
| Back Flow Preventer | A device to prevent backflow i.e. into a potable water supply. Usually required for sprinkler systems, handheld showers, pullout faucet spouts, kitchen sprayers, etc. |
| Back Pressure | Pressure that resists the flow of fluid in a piping system. |
| Back Siphonage | The negative pressure that causes backflow. |
| Backjet | Whirlpool jets located on the fixture wall behind a reclining bather. |
| Backjet Pulse Canister | A water-controlling device responsible for backjet pulsing action. |
| Back Vent | Plumbing fixture’s separate vent in a building drainage system. |
| Back Wash | The process of cleaning a filter by reversing the flow of water through it. Accumulated sediments are sent to waste. |
| Backup | Overflow of a plumbing fixture due to drain stoppage |
| 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 |
| Balancing Valve | A water heater valve that controls water flow and balances heat distribution to different locations. |
| Ball Check Valve | A valve that uses a ball to seal against a seat to stop flow in one direction. |
| Ball Joint | Spherical assembly allowing pivot rotations for showerheads. |
| Ball Passage | Refers to the size of the ball that can pass through the trap-way of a toilet. Also relates to trap-way size. Usually the trap size will be 1/8” larger than the maximum size ball that can pass through it |
| Ball Valve | A valve that uses a ball to seal against the seat. |
| Ballcock | Controls the flow of water from the water supply line into a gravity-operated toilet tank. It is controlled by a float mechanism in the tank water. |
| Balloon Bag | Device that attaches to a garden hose. Used to loosen drain blockage. |
| Barlow’s Formula | An equation that shows the relationship of internal pressure to allowable stress, nominal thickness and diameter. |
| Barrier-Free | Relating to handicap access, e.g. a shower enclosure system having minimal or no bottom track and openings that are wheelchair-accessible. |
| Basket Strainer | Basket-shaped strainer with holes and a slot that fits the sink drain to allow water to run out but to catch food or other solids before they can enter the sewage system. |
| Beehive Strainer | A strainer inserted into a urinal to prevent foreign matter from falling into the drain. |
| Bernoulli’s Law | The principle that a stream of liquid or gas exerts less sideways pressure while in motion than while at rest. As a result, fluids seem to be drawn into the stream, but are really pushed in by higher outside pressure. |
| Bidet | A personal hygiene plumbing fixture similar in appearance to a toilet bowl used for washing genitals and posterior areas of the body. It is mounted on the floor next to a toilet and consists of a washing basin, a hot and cold faucet, and sprayer. |
| Biochemical Oxygen Demand | The amount of oxygen consumed in the oxidation of organic matter by biological action under standard test conditions; often used as a measure of the strength of sewage and waste water. |
| Bisque | The rough, unpolished finish found in unglazed areas of vitreous china fixtures, such as inside the tank or the bottom of the bowl. |
| Blackwater | Wastewater from toilets or latrines and sinks used for food preparation or disposal, or for the disposal of chemicals. |
| Bleed | To drain a pipe of excess air by opening a valve at the end of the pipe |
| Blind Plug | Plug used on No Hub pipe. |
| Block Sensor Mode | For touch-less faucets, a system mode that occurs when the faucet continually senses an object, causing the faucet to stop functioning normally. The faucet will appear to be ”OFF”, and will self-actuate every two hours to alert you to its condition. |
| Blowbag | Also called a ”blowfish” it is a drain-cleaning device consisting of a rubber bladder with a hose fitting one one end and a nozzle on the other. The device attaches to a water hose and is inserted into a clogged drainpipe. As water is introduced, it expands to grip the pipe, and releases pulsating bursts of water through the nozzle, forcing water through the pipe to clear the obstruction. |
| Blowdown | Partial venting or draining, under pressure, of the water side of a boiler to reduce or remove unwanted contaminants. Also the pressure drop after releasing a pressure-relief valve. |
| Bodyspray | Shower component used in conjunction with a showerhead to deliver flow of water. Commonly used in multiples to create a custom shower space. |
| Boiler | A sealed tank where water is turned to steam for heating or power. |
| Boiler Feed | A check valve controlling inlet water flow to a boiler. |
| Bonnet | The top portion of a compression valve assembly that holds the valve in place as it is tightened against the valve seat at the other end. |
| Box | The internal (female) threaded end of pipe. |
| Box Flange | Flange containing internal (female) threaded pipe fitting |
| Brackish Water | Water containing bacteria between 1.000 and 15,000 ppm of dissolved solids |
| Braided Tubing | A flexible pressure tubing of synthetic material encased in braided threads of steel, usually chrome plated or stainless. The braiding protects the tube from damage due to abrasion or crimping. Often used in water supply lines. |
| Branch | Any part of a drain system other than the main, riser, or stack. |
| Branch Vent | A vent connecting one or more individual vents with a vent stack |
| Brine | A strong solution of sodium chloride (salt) used in the regeneration of ion exchange water softeners. |
| Building Drain | The lowest point in a drainage system where the interior drainage pipes meet and are conveyed it to the sewer. |
| Burst Pressure | The internal pressure that will cause piece of tubing to fail |
| Bushing | A pipe fitting used to join two pipes of different sizes. A bushing is threaded inside and out. Also a cylindrical part used as a lining or guide |
| Butterfly Valve | A valve made of a square, rectangular, or round disk attached to a shaft inside a body of the same shape. Rotating the shaft 90 degrees opens or closes the valve. |
| Buttress (Tile Rise) | The raised portion of a shower curb that is on more than one level. |
| Bypass | A type of shower door system that consists of two or more panels running in parallel tracks. |
| CBD | Certified Bathroom Designer |
| CC | Copper to Copper soldered. |
| CFM | Cubic Feet per Minute |
| CI | Cast Iron |
| CO | CleanOut |
| CP | Polished Chrome finish used on faucets |
| CPe | Solvent Chlorinated Polyethylene. A melting agent to form seams in shower pan liners |
| CPvC | Chlorinated Polyvinyl Chloride. Rigid plastic pipe used in water supply systems, where code permits. Withstands high temperatures. Available in straight or in rolls |
| CSST | Corrugated Stainless Steel Tubing. Also known as ”TracPipe” and has a polyethylene jacket. |
| CTS | Copper Tube Size. Refers to outside diameter and is used to size certain fittings and hangers |
| CW | Continuous Weld. A method of producing a small diameter pipe. |
| Calcium Carbonate | A white accumulation that forms in water lines, water heaters and boilers in hard water areas usually referred to as ”scale.” |
| Calcium Hypochlorite Extract | The matter adsorbed from a stream of water by activated carbon, and then extracted from the activated carbon with chloroform, using a specific standardized procedure; a measure of the organic matter in a water. |
| Calcium / Magnesium | Two of the principal elements that, when dissolved, make water hard. Their presence contributes to the formation of scale and insoluble soap curds. |
| Capacity | 1. Pumps: The flow rate in gallons per minute or liters per minute. \n2. Water softeners / conditioners: Quantity of undesirable matter that can be removed by a water conditioner under standard test conditions. For ion exchange water softeners, this is expressed in grains of hardness removal between regeneration’s and is related to a pound of salt used.\n3. Water filters: For filters, capacity may be expressed in the length of time or total gallons delivered between servicing.\n4. Water heaters: The size in gallons of water of the storage tank (e.g. 40 gal, 75 gal, etc) |
| Carbon Dioxide (CO2) | 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. |
| Carbonate Alkalinity | Alkalinity due to the presence of the carbonate ion (CO32-). |
| Carbonate Hardness | Water hardness due to the presence of calcium and magnesium carbonates and bicarbonates in water; the smaller of the total hardness and the total alkalinity. |
| Carbonizing | In a pump, where a reduction of hydrocarbons results in the formation of carbon residue that will interfere with the movement of a mechanical seal. Often called coking. |
| 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. |
| Cast Iron | Heavy metal made of casting on molds to make fixtures such as sinks, tubs and lavatories, covered with a porcelain enamel coating. Casting is made of a series of alloys primarily of iron, carbon, and silicon. |
| Cast Iron No Hub Pipe | Also known as Soil Pipe, No Hub pipe is used in certain locales and for commercial buildings for soil stacks. It cannot be soldered, threaded, or welded, and can only by connected by steel banded rubber sleeved adapters. |
| 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.. |
| Cavitation | The vacuum created when the discharge capacity of the pump exceeds the replacement in the suction line. This causes bubbling and vibrations that can damage the pump if they occur over an extended period. |
| Celcon Nut | Connectors used to hand-tighten faucets to lavatory from underside of lavatory |
| Centerset | Style of bathroom faucet having combined spout and handles, with handles 4 inches apart, center-to-center. Also a single-handle faucet installed on 4 inches center-to-center faucet holes. |
| Centrifugal Pump | A pump that moves water by centrifugal force developed by rapid rotation of an impeller.. As the rotating impeller whirls the water around, centrifugal force builds up pressure forcing the water through the discharge outlet. |
| Chain Wrench | An adjustable wrench in which a chain is used for gripping. Commonly used on large pipes. |
| Chamfer | Beveled end, usually done on pipe prior to threading |
| Check Valve | A type of backflow preventer installed in a pipe run that allows water to flow in only one direction. |
| Circuit Vent | Plumbing drainage system vertical vent which is run from the last two traps on a horizontal drain line to the main vent stack of a building drainage system. |
| Cistern | Rainwater storage tank, often underground. |
| Cleanout Plug | A plug in a trap or drain pipe that provides access for the purpose of clearing an obstruction. |
| Close Coupled | A toilet with a separate tank and bowl, secured to each other, and with a separate tank cover. Also known as a two-piece toilet. |
| Close Nipple | Short lengths of pipe that are threaded on both ends. The threads that are so close together they almost join in the center. |
| Closed System | A system where the incoming cold water supply has a device that will not allow water to expand when heated. (i.e. check valve, backflow preventer, pressure reducing valve, etc.) |
| Closet Auger | A flexible rod with a curved end used to access the toilet’s built-in trap and remove clogs. |
| Closet Bend | A curved fitting mounted immediately below the toilet that connects the closet flange to the toilet drain |
| Closet Flange | An anchoring ring that attaches to the closet bend and secured to the floor. The heads of closet bolts, used to secure the toilet in place, insert into slots in the closet flange. |
| Closet Tube | A water supply tube used for toilets. |
| Coagulant | A material, such as alum, which will form a gelatinous precipitate in water, and cause the agglomeration of finely divided particles into larger particles which can then be removed by settling and/or filtration. |
| Coagulant Aid | A material which is not a coagulant, but which improves the effectiveness of a coagulant, often by forming larger or heavier particles, speeding the reactions, or permitting reduced coagulant dosage. |
| Coagulation | The process in which very small, finely divided solid particles, often colloidal in nature, are agglomerated (lumped) into larger particles. |
| Cock | A faucet or valve for regulating the flow of water. |
| Cockhole | Cover A round cover-plate or disk installed on a sink to cover an unused faucet hole. |
| Coil Spring Tube Bender | A flexible heavy-wire coil, which, when slipped over copper tubing, allows it to be bent without crimping. |
| Coking | In a pump, where a reduction of hydrocarbons results in the formation of carbon residue that will interfere with the movement of a mechanical seal. Also referred to as ”Carbonizing”. |
| Cold Drawn | Pipe or tubing that’s pulled through a die to reduce diameter and wall Produces closer tolerances and higher strength Cold Vapor Method to test water for the presence of mercury. |
| Coliform | Bacteria Non-pathogenic microorganisms used in testing water to indicate the presence of pathogenic bacteria |
| Collar | A galvanized sheet metal restricting device used in conjunction with plastic pipe. Its function is to direct and control the expansion action of the firestopping material |
| Colloid | Very finely divided solid particles that remain suspended in a solution; the removal of colloidal particles usually requires coagulation. |
| Combined Sewer | A sewer system that carries both sanitary waste and storm water runoff. |
| Combustion Chamber | The location where combustion takes place. |
| Combustion Gases | Gases released when a gaseous, liquid, or solid fuel reacts at an elevated level that needs to be vented with gas or oil-fired water heaters. |
| Commode | Toilet. |
| Common Vent | Building drain system vertical vent which connects two or more fixture branches on the same level. |
| Compensated Hardness | A calculated value based on the total hardness, the magnesium to calcium ratio, and the sodium concentration of a water. It is used to correct for the reductions in hardness removal capacity caused by these factors in cation exchange water. |
| Composite | Composite sinks made from high-tech, high-strength, color- impregnated that resists shipping and scratching. |
| Composting Toilet | A self-contained toilet that use the process of aerobic decomposition (composting) to break down feces into humus and odorless gases |
| Compression Fitting | A kind of tubing or pipe connection where a nut, and then a sleeve or ferrule is placed over a copper or plastic tube and is compressed tightly around the tube as the nut is tightened, forming a positive grip and seal without soldering. Also a flexible connector that has a nut and gasket designed to attach directly to an SAE standard compression thread, without the use of a sleeve or ferrule. |
| Compression Valve | A type of valve that is often used for water faucets. It is opened or closed by raising or lowering a horizontal disk by a threaded stem. |
| Concealed Arm Carrier | One of a variety of common mechanisms to securely mount a wall-mount lavatory. Unlike a hanger which only supports the lavatory where it meets the wall, the carrier has long arms onto which the lavatory slides. |
| Condensation | Water vapor that separates from products of combustion due to a reduction in heating surface temperatures to below the dew point of surrounding air. Water formed when water vapor formed in gas combustion loses heat before it passed out of the venting system. |
| Conductance | In water conditioning, the readiness of water to carry electricity. The unit of measure for conductance is the mho (reciprocal ohm); it is used to approximate the dissolved solids content of water. |
| Conductivity | The quality or power to carry electrical current; in water, the conductivity is related to the concentration of ions capable of carrying electrical current. |
| Conduit | A tube that houses electrical wiring. |
| Conduit Clamp | A screw-down, U-shaped spring clamp formed out of a band of metal used to hold conduit pipe. |
| Console Lav | A table-like fixture with an integral lavatory. The back is fixed to a wall and the front is supported by brackets or legs. |
| Console Table | Same as console lav. |
| Consumptive Water Use | Total amount of water used by vegetation, man’s activities, and evaporation of surface water |
| Continuous Hinge Door | A shower door that has a full-length continuous metal hinge on the side of the door. |
| Conventional Vent | Atmospheric venting that utilizes the natural convective rise of hot flue gases through the system to release the products of combustion. |
| Corporation Stop | The stop connected to the water main, usually made of brass and can be connected to the main with a special tool without shutting off the municipal supply. |
| Corrosion | The disintegration of a metal by electrochemical means. |
| Corrosive Water | A water condition of low pH (acid condition) that can corrode metal pipes, pool fixtures and pumps. (Unbalanced water) |
| Cowl | A short fitting used to join two pieces of pipe. |
| Crocus Cloth | Finer than sandpaper grit on a cloth backing |
| Cross-Connection | Any connection or situation that may allow wastewater to enter the supply system. |
| Crow’s Foot | A PVC tee with twin outlets at right angles off the main. |
| Crown-vented Trap | An air admittance valve attached to a drainpipe, protected by a check valve, designed to equalize pressure in the drain line and to protect the trap seal. |
| Crown Weir | The interior projection in the outlet side of a P-trap to aid in maintaining the water seal in the trap. |
| Cubic Foot of Gas | The amount of gas that will occupy one cubic foot at a temperature of 60 degrees F, and under a pressure equivalent to that of 30 inches of mercury. |
| Culvert | A pipe-like construction of concrete that passes under a road to allow drainage. |
| Curb | A raised edge or border of a shower, usually made of tile, marble, or fiberglass. |
| Curb Cock Shutoff | A valve normally used with water meters set between the meter and the building. |
| Curtain Drain | A ditch sometimes filled with gravel or drainage tile which diverts storm water away from a structure |
| Cut Lengths | Pipe cut to a specific length as ordered |
| DI | Abbreviation for ”deionization” |
| DWV | Drainage, waste, and vent systems, which remove wastewater. Not for drinking water. |
| Dam | The barrier built into a trapway of a toilet that controls the water level in the toilet bowl. |
| 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. |
| Deep Well | A well more than 25 ft. deep |
| Degree Rise | The difference between the starting water temperature and the ending temperature after heating is complete. |
| Deionization | The process of reducing water to a non-mineral state by passing it over a bed of resins |
| Deionized Water | Water free of inorganic materials. |
| Desanco Fitting | A type of compression adapter that connects tubular brass fittings to pvc pipe. |
| Dew Point | Temperature at which water vapor condenses to a liquid. |
| Dial Plate | Trim piece found behind a single-control wall-mount faucet handle. Also known as a face plate. |
| Diaphragm | Flexible membrane in a valve that deflects down onto a rigid area of the valve body to regulate water flow from the supply lines. This eliminates the possibility of debris build-up within the valve. |
| Die | Cutting device used to thread pipe. A set of these attach to die-heads, and mounted on a threading device. |
| Diffuser | Device for reducing the velocity and increasing the static pressure of a fluid passing through a system |
| Dilution Air | Air that enters a draft hood or draft regulator and mixes with the flue gasses. |
| Dip Tube | Tube inside the water heater that sends cold water to the bottom of the tank. |
| Direct Tap | Clamping device that allows a branch line to be drilled and tapped off a main line. |
| Direct Vent | A system that pulls outside air for combustion and vents combustion gases directly outside without using a chimney. |
| Directional Jet | Whirlpool air discharge unit with pivot allowing discharge path to be adjusted by the user. Directional Tee Tee fitting that allows direct flow in one direction by use of an internal baffle. |
| Discharge Head | Difference in elevation between the liquid level of the discharge tank and the centerline of the pump. Also includes any additional pressure head that may be present at the discharge tank fluid surface. |
| Discharge Tube | Outlet tube that connects a disposer or sump pump to the drain line. |
| Disposal Field | A series of trenches conveying the effluent from the septic tank laid in such a manner that the flow will be distributed with reasonable uniformity into natural soil. |
| Dishwasher Tailpiece | A flanged adapter connecting a basket strainer to the drainpipe with a dishwasher inlet. |
| Diverter | A valves that directs fluid to various outlets. They are used in showers, tubs, bidets, and sinks. |
| Dope | Pasty lubricant used on seal pipe threads prior to making a threaded pipe connection. |
| Double Extra Strong | Standard pipe weight designation (XXS). Sometimes described as XXH (double extra heavy). |
| Double Horizontal Tee | A PVC tee with twin outlets of a smaller diameter than the inlet. |
| 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. |
| Double Suction Pump | A pump where the rotor is suspended between two bearings with the fluid entering on either side of the impeller. Used at higher capacities. |
| Double Wye Fixture | A fitting that has branches coming in at an angle from each side of the main to join the main run. |
| Down Head Boring Gimlet | A flexible cutting tip for an auger cable. |
| Draft Diverter | A device fitted in the flue way of a gas appliance to prevent updraft, downdraft, or the secondary flue blockage from obstructing the escape of combustion gases. |
| Drain | Any pipe that carries wastewater or water-borne waste. |
| Drain Hub | Floor drain used with hubbed soil pipe. The bell (hub) section is counter-sunk vertically in the floor and covered by a flush-mounted grill. |
| Drain Seal Gasket | Gasket used to seal a drain to a sink to prevent leaks. |
| Drain Valve | Device designed to allow drainage of stored contents from a water heater. |
| Drainage Tile | Pipe-shaped clay tiles installed in below-grade trenches for gravity-rated drainage. PVC pipe is now commonly used for this purpose. |
| Drawdown | The distance the water level drops below the standing water level while the pump is operating. |
| Drip Channel | A metal channel that is designed to prevent water running down a shower door from dripping onto the floor when the door is opened. |
| Drip Leg | A stub end pipe placed at a low point in the gas piping to collect condensate and permit its removal. |
| 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. |
| Duostrainer | Sink drain fitting consisting of a strainer body attached to the drain opening and a removable basket. Also called a strainer. |
| Duo Valve | A twin valve (hot & cold) with a single on/off lever used for washing machine boxes |
| Duplex Basin | An ejector pump container, usually 30” x 36” or 36” x 36” large enough for two pumps, used in multi-family buildings |
| Duraflow | A process patented by Ace Duraflow Company to rejuvenate old corroded plumbing by cleaning and lining with an Epoxy coating. |
| Dynamic Pressure | The pressure when the water is flowing. |
| E. Coli | The common abbreviation of Escherichia Coli. One of the members of the coliform groups of bacteria indicating fecal contamination. |
| ECO | Energy Cut Off. A safety device designed to shut power off to the water heater and prevent high temperature. |
| EF Energy Factor | A measure of the overall efficiency rating of the water heater based on the model’s recovery, efficiency, stand-by loss and energy input. |
| EMT | Electrical Metal Tubing. A thin wall galvanized steel pipe used to carry electrical or other types of conductors. |
| ERW | Electric Resistance Weld. Most common form of manufacture for pipes 2 3/8” to 22” in diameter. |
| Earthquake Strap | A metal strap used to secure a water heater to the house frame or foundation. |
| Eccentric Shank | A shank or the fitting with a shank in which the centerline is offset to allow minor compensation for supply lines that would be difficult to precisely position. |
| Eductor | A device utilizing a nozzle and throat, installed in a stream of water to create a partial vacuum to draw air or liquid into the stream; commonly used to draw regeneration chemicals into an ion exchange water treatment system, such a softener or deionizer. |
| Efficiency | A product’s ability to utilize input energy, expressed as a percentage. |
| Effluent | Septic system liquid waste |
| Ejector | A mechanical device for pumping sewage from below the sewer line. |
| Elbow | A fitting with two openings that changes the direction of the line. Also known as an ell. It comes in various angles from 22 degrees to 90 degrees; often referred to by their angles (i.e. 45, 90) |
| Electric Resistance Weld Pipe (ERW) | Cold finished pipe made by a series of operations in which the flat rolled material is cold shaped into tubular form and welded at the seam. The heat for the weld is generated at the seam by the resistance to the flow of electric current applied through electrical contacts or an induction coil. |
| Electrodialysys | A process which uses an electrical current and an arrangement of permeable membranes to separate soluble minerals from water. It is often used to desalinate salt or brackish water . |
| Electrolysis | A process involving chemical change caused by the passage of an electric current through a liquid. |
| Electrolyte | A nonmetallic substance that carries an electric current, or a substance which, when dissolved in water, separates into ions which can carry an electric current. |
| Element | Heating unit in an electric water heater |
| Elevation | The vertical distance between the level where fluid enters a pipe and the level where it leaves. It must be added to the Total Discharge Head if the inlet is lower than the outlet and subtracted if the inlet is higher. |
| Elongated | The shape of a some toilet bowls, where the bowl is about 2 inches longer than the standard round front bowl, usually 14 inches wide by 18 inches long. |
| Enamel | An opaque vitreous composition applied by fusion to the surface of metal fixtures such as cast iron and pressed steel tubs, lavs, and sinks. Enameled steel is less durable than enameled cast-iron. |
| Enclosure | Panels of glass or other material used to form shower or tub stalls. |
| End Body | A faucet valve body configuration in which both the inlet and outlet are at the end of the valve body. |
| End Drain | The side of a tub where the drain is found. When facing a tub, if the drain is on the right, this is a Right-Hand tub (RH). If on the left, it is a Left Hand tub (LH). On whirlpools, the pump is located opposite the drain. |
| Endpoint | (1) The point at which a process is stopped because a predetermined condition is met;\n(2) in an ion exchange water softener service run, this is where the hardness of the softener effluent increases to a predefined concentration, often 1.0 grain per gallon;\n(3) in a filter service this may be where the pressure drop across the filter reaches a predetermined value. |
| Energy Guide Label | The label required by the FTC on water heaters that show 1) an estimated annual cost of operation and 2) how that unit’s efficiency compares to all other comparable models. |
| 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) |
| Expansion Valve | Thermostatically controlled valve that controls liquid refrigerant. |
| Extinction Pop | A flashback occurring when a burner is turned off. |
| Extra Strong | A standard pipe weight designation (XS). Sometimes called XH (Extra Heavy) |
| Extrusion | Refers to the result of forcing molten metal or plastic through a die or mold to form a specific shape. Commonly refers to shower door components such as jambs and headers that were created by extrusion. |
| Eye of the Impeller | The center of the impeller, where the fluid enters. |
| F Rating | A rating of effectiveness of firestop material, measuring its resistance to flames and water. |
| FHT | Female Hose Thread. (e.g. end of garden garden hose) |
| FIP | Female Iron Pipe connection. Standard internal threads on pipe fittings. |
| FMA | Free Mineral Acidity. |
| FMPX | Female pipe swivel connection |
| FNPT | This refers to the female pipe thread, in which the threads are on the inner side of the connection fitting |
| FVI | Flammable Vapor Ignition |
| Facultative Bacteria | Bacteria that can live under aerobic or anaerobic conditions |
| Fall / Flow | The proper slope or pitch of a pipe for adequate drainage. |
| Fascia | A decorative apron or front face. A wooden enclosure holding the main pump assembly for whirlpool and master baths. |
| Faucet Threads | Special thread size for fittings that connect to faucets. A cone seal or gasket is usually included because straight threads will not have a complete seal without a gasket. |
| 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 |
| Feed Pump | A pump that supplies water to a boiler. |
| Feed Water | Water introduced into a boiler during operation. It includes make-up and return condensate. |
| Female Fitting | A fitting that receives a pipe or fitting. A fitting into which another fitting is inserted. |
| Female Threads | Faucet threads that are in place on the inside of a fitting. |
| Ferrous | Material containing or derived from iron. |
| Ferrule | Metal cover piece for the lavatory overflow opening. |
| Filter Element | A device within a filter tank designed to trap suspended solids as water flows through it. |
| Filtrate | Liquid that has been passed through a filter |
| Filtration Rate | The rate at which the water is traveling through the filter, measured as GPM (gallons per minute) per sq. ft. |
| Finish Plumbing | Installation of plumbing fixtures to make the system usable. |
| Finished Water | Water that has completed a purification or treatment process. |
| Fire Hose Closet | Usually a compartment built into an interior wall, covered by a glass door, holding a coiled fire hose connected to a water line, ready for immediate use in case of fire. |
| Fire Stand Pipe | A main water line that feels water sprinkling system or fire hose connections. This is separate from the lines feeding restrooms or other fixtures. |
| Firestop | Materials that fill the opening around penetrating items such as cables, cable trays, conduits, ducts, and pipes and their means of support through the wall or floor to prevent spread of fire. |
| First Draw | Water that has been sitting in pipes or plumbing fixtures overnight and is first drawn when taps are opened in the morning. For instance, where lead is present in plumbing, this water would have the highest levels of lead contamination. |
| First Hour Delivery | Rating based on the combination of the usable stored volume of hot water in a tank plus the recovery capacity for the first hour of operations. |
| Fitting | Any pipe part used to join together two sections of pipe, such as elbows, couplings, bushings, bends, wyes, etc. |
| Fixed Cone Valve | A cylinder gate mounted with the axis horizontal. Also known as Howell Bunger valve. |
| Fixture | A device that provides a supply of water or its disposal, e.g. sinks, tubs, toilets. |
| Fixture Unit | An arbitrary unit assigned to different types of plumbing fixtures, and used to estimate flow rate requirements and drain capacity requirements. |
| Flame Stability | Flames on a burner tend to stabilize at a point where flow velocity out and burning back are equal. It changes when primary air or gas rate is adjusted. |
| Flange | Extending rim or edge at one end of a pipe shaft that gives support or a finished appearance. |
| 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. |
| Flapper Valve | The part on the bottom of the toilet tank that opens to allow water to flow from the tank into the bowl. |
| Flare Fitting | A fitting used to connect flex copper pipe, usually gas pipe |
| Flaring Tool | Tool used to create a cone-shaped enlargement at the end of a piece of tubing to accept a flare fitting. |
| Flex Coupling | Rubber coupling used to join DWV Pipe. Can be used to connect PVC to Clay or Cast Iron above or below ground. Also used for repairs, and attach by used of steel band clamps. |
| Flexible Connector | A braided hose that connects a faucet or toilet to the water supply stop valve. Serves as a riser but is much more flexible and easier to install. Usually stainless steel or PVC/Polyester reinforced hose. |
| 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. |
| Floating Flames | An undesirable burner operating condition, usually indicating incomplete combustion in which flames leave the burner port to ”reach” for combustion air. |
| Flocculant | A chemical substance that promotes the aggregation or coagulation of suspended particles in the water. |
| Flood Level Rim | The top edge of a receptacle from which water overflows. |
| Floor Drain | Drainage fitting that sits flush with the floor, used in basements and showers. |
| Floor Flange | A fitting that connects a toilet to a floor drain. |
| Floor Sink | Receptacle usually made of enameled cast iron located at floor level and connected to a trap to receive the discharge from indirect waste and floor drainage. Cleaner and more sanitary than regular floor drains. Usually used in hospitals & restaurants. |
| Flow Control Valve | Device designed to reduce water flow to a plumbing fixture. Often used to improve efficiency and reduce operating costs. Also a check valve that prevents flow reversal when heater is turned off. |
| Flow Rate | Rated in gallons per minute (GPM) or in gallons per hour (GPH) |
| Flue | A passageway for combustion by-products. |
| Flue Baffle | A device to deflect, check, or regulate flow through a pipe. |
| Flue Damper | A device to minimize heat loss through a venting system. |
| Flue Exhauster | A fan installed in the vent pipe which will provide a positive induced draft. Sometimes called a draft inducer. |
| Flume Spout | An open spout design that is also referred to as a waterfall spout. |
| Flush Joint | A Connection with both male and female threads cut into the pipe. |
| Flush-Mount Lavatory | Sink that sits flush and even with the countertop and is supported by a metal ring. |
| Flushing Surface | The interior surface of the bowl and all other surfaces which may come into contact with water during flushing. |
| Flushometer | Toilet valve that automatically shuts off after it meters a certain amount of water flow. |
| Flushometer Tank System | Toilet flushing system that uses supply water pressure to compress water to provide a pressurized flush as opposed to a gravity flush. |
| Flushometer Valve | The valve located at the bottom of a gravity-operated toilet flush tank, which opens when the trip lever is actuated, and closes when the tank has drained to the desired level. Usually also contains an overflow tube. |
| Flux | Paste applied to copper pipes and fittings before soldering to help the fusion process and prevent oxidation. |
| Foam Insulation | Insulation surrounding the surface of a water heater tank. |
| Foot Valve | A special type of check valve located at the bottom end of the suction pipe on a pump; it opens when the pump operates to allow water to enter the suction pipe but closes when the pump shuts off to prevent water from flowing out. |
| Footprint | The area of floor space taken up by a water heater or other appliance. Framed A bath enclosure system that mounts all glass or plastic panels in a metal frame. |
| Frameless | A bath enclosure system that minimizes the amount of metal used to hold the system panels and door in place. |
| Free-Standing | Term used to describe a bathtub that is free of walls on all sides. |
| Free Available Chlorine | The concentration of residual chlorine present as dissolved gas, hypochlorous acid or hypochlorite, not combined with ammonia or in other less readily available form. |
| Freeboard | The vertical distance between a bed of filter media or ion exchange material and the overflow or collector for backwash water; the height above the bed of granular media available for bed expansion during backwashing; may be expressed either as a linear distance or a percentage of bed depth. |
| French Drain | A covered ditch containing a layer of fitted or loose stone or other pervious material. |
| Friction Head Difference | The difference in head required to move a mass of fluid from one position to another at a certain flow rate within a piping system. It is also the specific energy required to overcome friction in the system. |
| Friction Loss | The loss of pressure caused by the turbulence created in water while traveling through the pipe. |
| Frost Line | The depth to which frost penetrates the earth. |
| Full-Finished | Refers to tubular products in which the weld has been processed to produce uniform strength and dimensions, and subsequently annealed to obtain proper corrosion resistance. |
| Full Hydraulic Capacity | The designed capacity of a pipe or conduit. |
| Ga. | Abbreviation for gauge, the wall thickness of tubing |
| GAMA | Gas Appliance Manufacturers Association |
| GFCI | Ground Fault Circuit Interrupter. A device to cut off the flow of electricity if a short circuit is detected. |
| GPF | Gallons Per Flush used in toilets. Current law requires maximum of 1.6 gpf. Older styles were usually 3.5 gpf. |
| GPG | Grains Per Gallon. A measurement of the amount of dissolved material in water. One grain per gallon equals 17.1 ppm |
| GPH | Gallons Per Hour. A measure of flow rates. |
| GPM | Gallons Per Minute. The rate of flow by which faucets and showerheads are measured and regulated. |
| Galvanic Action | The phenomenon of corrosion of an anode (positive terminal – like on a battery). When two dissimilar metals are immersed in an electrolyte, an electrical potential will exist between them. If the two are in an electrical contact, a current will flow. The metal that becomes the anode (negative) of this cell will corrode and dissolve while the cathode (positive) will be protected from corrosion. |
| Galvanic Series | A list of metals with those on the top of the list being attacked by those lower down in the list. The father apart on the list, the faster the attack. |
| Galvanizing | The process of applying a coating of zinc to the finished product to provide corrosion protection. The coating can be applied by hot dipping or electrolytic deposition. |
| Galvanometer | Laboratory instrument that detects and measures small electric current. |
| Gas Cock | Plug valve installed the main gas line and an appliance. |
| Gas Control Device | Is used to regulate gas pressure on a water heater. |
| Gasket | Flat device usually made of fiber or rubber used to provide a watertight seal between metal joints. |
| Gate | A device that controls the flow in a conduit, pipe, or tunnel. |
| Gate Diverter | The pop-up lever on a tub faucet that activates the diverter valve |
| Gauge (gage) | Device for registering water level, discharge, velocity, pressure, etc. A number that defines the thickness of the sheet used to make steel pipe. The larger the number, the thinner the pipe wall. |
| Gel / Grease Cap | Waterproof wire connector. |
| Gland | In a pump, the part that holds one half of the mechanical seal and attaches to the stuffing box. |
| Glaze | Glossy water-resistant, colored finish on vitreous china fixtures. |
| Globe Valve | A gate valve with a curved chamber. |
| Grab Bar | Safety bar installed in a bathtub or shower for use when bathing. |
| Gravity Operated Toilet | A toilet that relies on the natural downward pressure of water in a toilet tank to flush the toilet effectively. |
| Grains Per Gallon (gpg) | A common basis for reporting water analyses in the United States and Canada; one grain per U.S. gallon equals 17.12 milligrams per liter (mg/1) or parts per million (ppm). One grain per British (Imperial) gallon equals 14.3 milligrams per liter or parts per million. |
| Gray Water | Waste water from sinks, showers, and bathtubs, but not toilets. |
| 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. |
| Greensand | A natural mineral, primarily composed of complex silicates, which possesses ion exchange properties. |
| Grip Fitting | A compression-type fitting used on PB pipe. |
| Grooved Fitting | A gasketed mechanical pipe fitting made of ductile iron that is clamped onto a groove in a pipe rather than screwed onto threads. It is mostly used in commercial applications on pipes larger than 1 1/2” in diameter. |
| Ground Joint | A joint which consists of pressing two smooth mating surfaces together without a gasket or supplemental sealant. |
| Ground Joint Union | Pipe union that has a brass grounding section between the two halves. |
| Ground Water | Naturally occurring water rising from the water table of the surrounding land. |
| Grounding | Connecting a piece of electrical equipment to a ”ground wire” which is connected to the electrical system ground at the circuit breaker box. This helps to ensure that the circuit breaker will trip and cut off power in the event of a short circuit or damage to insulation. |
| Guide Arm | Valve which controls water flow into the toilet tank. |
| HBA | Home Builders Association |
| HD | Head |
| HP | Horsepower |
| HT | Hose Threads. Note: Garden hose threads are different from standard pipe threads. |
| HVAC | Heating, Ventilation, and Air Conditioning. |
| Hand-shower | A showerhead designed with a handle that’s connected to a water supply and a flexible hose. |
| Hanger | A device used to support pipes. |
| Hard Water | Natural water containing impurities in various proportions. Traditional hardness is a measure of calcium or dissolved solids in a solution, measured in parts per million. Hard water generally ranges from 100 to 250 ppm. |
| Hardness | The amount of dissolved minerals in water measured in grains per gallon (GPG). The most common minerals are calcium and magnesium. |
| Hardness Leakage | The presence of a consistent concentration of hardness in the effluent from an ion exchange water softener, often due to high concentrations of hardness or sodium in the water being treated (see Leakage). |
| Head | The pressure of water (or steam) in a closed system (see Pressure Head). It represents the differential in the gravitational force exerted by a liquid at two different depths. |
| Head Loss | The pressure of water as measured at a stated point, either in feet or in pounds per square inch (PSI). |
| Heat Exchanger | A heat transfer system. |
| Heat Sensors | Heat-triggered devices on sprinkler systems that release the flow of water. |
| Heat Trap | Restriction of heat loss through water connections to a tank. |
| Hermetic | Completely sealed, especially against the escape or entry of air. |
| Hold Down | A type of pipe anchor consisting of a U-strap bolted at either end onto a horizontal plate. |
| Hollow-jet Valve | A valve having a closing member that moves upstream to shut off the flow. The hollow-jet valve discharges a hollow or annular jet dispersed over a wide area. |
| Horizontal Branch | Lateral drain pipes that run from plumbing fixtures to the waste stack in a building or in the soil. |
| Horizontal Run | The horizontal distance between the point where fluid enters a pipe and the point at which it leaves. |
| Hose Bibb | An outdoor faucet, also used to supply washing machines. |
| House Trap | U-shaped fitting with two adjacent cleanout plugs visible at floor level if main drain runs under floor. |
| Hub & Spigot Piping | Gravity rated DWV or pressure pipe that has a bell-shaped section at one end and a straight section at the other. As lengths are assembled, the straight end of one fits into the bell of the next. |
| Hydration | The chemical absorption of water into a substance. |
| Hydraulic Pressure | Pressure that exists in a system containing non-compressible liquid. |
| Hydrolysis | The reaction of a salt with water to form an acid and a base. |
| Hydronic | System of forced hot water. |
| Hydrojet | Cold inlet tube designed to reduce sediment build-up and increase efficiency in a water heater. |
| Hydro Jetting (Service) | The process of clearing blocked pipes using high pressure water as a boring and flushing mechanism. More on Hydro Jetting Service |
| Hydrostatic Pressure | Pressure exerted by or existing within a liquid at rest with respect to adjacent bodies |
| Hydrostatic Test | Test using non-compressible liquid under pressure at a level equal to or greater than the maximum pressure that will be utilized when in use, such as in steam boilers. |
| Hypochlorite | The OCL anion; calcium and sodium hypochlorite are commonly used as bleaches and disinfecting agents. |
| ID | Inside diameter. All pipes are sized according to their inside diameter. |
| IPS | Iron Pipe Size (OD). Same as NPS. Standard pipe threads. Also Internal Pipe Swivel connection (female) |
| ISO | International Standards Organization based in Geneva Switzerland. Among the many standards it issues are pump and seal standards for the metric community. |
| ISO 9000 | A series of five standards for developing a total quality management system. Developed by the International Standards Organization |
| Immersion | A term referring to something submerged in water. |
| Impeller | Rotating wheel with vanes found inside a centrifugal pump. As it spins at high speed it draws fluids in and thrusts them under pressure to the discharge outlet. |
| Incomplete Combustion | A product of inadequate ventilation which restricts the flow of air into an appliance. This may lower oxygen content in the surrounding air. |
| Incoming Inlet Temperature | Temperature of water entering the tank. |
| Indirect Waste Pipe | Waste pipe used to convey gray water by discharging it into a plumbing fixture such as a floor drain. |
| Induction Motor | The most common type used in industry. Has a slippage of 2 to 5 percent compared to synchronous motors. |
| Influent | The stream entering a unit, stream or process, such as the hard water entering an ion exchange water softener. |
| Injection | The drawing of primary air into a gas burner by means of a flow of fuel gas. |
| Inlet | An entrance, opening, or aperture for the intake of fluid or gas. |
| In-line Pump | Small pump which pumps fluid through a line on which it is supported and mounted. |
| Input | The amount of fuel used by a water heater in a given period of time, usually 1 hr. |
| Input Rate | The quantity of heat or fuel supplied to an appliance, expressed in volume of heat units per volume of time (BTUs/hour). |
| Input Rating | The gas burning capacity of an appliance in BTU’s per hour as specified by the manufacturer. |
| Insert Fittings | Fittings equipped with external, annular rings fir gripping, which are inserted into flexible rubber or plastic tubing as a connection. |
| Ion Exchange | A reversible process in which ions are released from an insoluble permanent material in exchange for other ions in a surrounding solution; the direction of the exchange depends upon the affinities of the ion exchanger for the ions present, and the concentrations of the ions in the solution. |
| Ionization | The process in which atoms gain or lose electrons; sometimes used as synonymous with dissociation, the separation of molecules into charged ions in solution. |
| Island Vent | An air admittance valve. |
| Isolation Mount | The four small rubber feet located beneath a whirlpool’s pump base, or attached to the pulse canister assemblies, designed to reduce noise and vibration when the whirlpool is running. |
| Instantaneous Water Heater | A type of water heater that heats water as it flows through a heat exchanger coil. |
| Insular | Kohler’s registered trade name for factory-installed insulation, which minimizes condensation on the outside of the tank when exposed to high humidity. |
| Insuliner | Kohler’s Registered trade name for factory-installed tank insulation, which minimizes condensation on the outside of the tank (also known as tank sweating) when exposed to high humidity. |
| 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 back-flowing into the fresh water supply. |
| Interceptor | Device for separating grease and oil from drainage system. (See grease trap.) |
| Isothermal | Action that takes place with no change in temperature. |
| JTU | Jackson Turbidity Unit |
| J Bend | The trap section, with a 180-degree bend, or a multi-piece P-trap. Also called a return bend. |
| J Hook | A pipe hanger in the shape of a ‘J’. |
| Jacket | Usually refers to the heating/ cooling jacket surrounding the stuffing box on some pumps; The outer casing (shell) of a water heater. |
| Jackson Turbidity Unit | (JTU) A quantitative unit of turbidity originally based on the comparison of a liquid (such as water) with a suspension of a specify type of silica, using the turbidity measure in a Jackson Candle Turbidimeter. |
| Jet | An orifice or other feature of a toilet that is designed to direct water into the trapway quickly to start the siphon action. |
| Jetport | Hydro-jet dip tube, which creates turbulence in the tank. |
| Johnni-bolts | Closet bolts, used to mount toilet bowls to the closet flange. |
| Joint | One length of pipe. |
| Joint Runner | Collar like device that keeps molten lead in place while sealing a joint in cast iron pipe. |
| Junction Box | Utility area where incoming current is connected in an electrical appliance. |
| kPa | Kilopascal. A metric unit for pressure. 100 kPa = one atmosphere. |
| KW | Kilowatt. A measure of the rate of supply of energy or power, equal to 1000 watts or 3412 BTU per hour. |
| Kafer Fitting | Cast iron drainage pipe fitting with threaded-on hub used to attach to existing cast iron lines |
| Kilowatt | One thousand watts. |
| Knockout Plug | PVC test plug |
| Kollar Kap | Styrofoam forms used to protect floor drains while concrete is being poured around them. |
| L Tubing | An industry standard for copper tubing defined by the tube wall thickness and identified by a ”blue” strip. Type ”L” copper tube wall is approximately 50% greater thickness than Type ”M” |
| LDO | Lint, Dust, and Oil |
| LP | Liquid Propane. A fuel for gas water heaters. |
| Laminar Flow | Streamlined flow of a fluid near a solid boundary. |
| Laminated Glass | Glass that has been made by uniting layers of glass in order to strengthen the glass. |
| Langelier’s Index | A calculated number used to predict whether or not a water will precipitate, be in equilibrium with, or dissolve calcium carbonate. It is sometimes erroneously assumed that any water that tends to dissolve calcium carbonate is automatically corrosive. |
| Lateral Sewage Line | A sewage line that connects one sewage pipe with another. |
| Laundry Tray | Laundry Tub |
| Laundry Tub | Very deep sink used in a laundry room for soaking or washing clothing. |
| Lav | Lavatory |
| Lav Tube | Water supply tube for lavatory. |
| Lavatory | A fixed bowl or basin with running water and drainage for washing. Bathroom sink. |
| Leach Field | Porous soil area, through which septic tank leach lines run, emptying the treated waste. |
| Leach Lines | Pipes that carry effluent from the septic system out to the leach field. |
| Leakage | Loss of fluid usually due to mechanical breakdown or gasket wear. |
| Lean Mixture | An air-gas mixture that contains more air than needed for complete combustion of the gas. |
| Leader Pipe | A pipe that carries rainwater to the ground or sewer. |
| Lien | A legal right to hold another’s property, or to have it sold, or applied for payment of a claim, especially to satisfy a debt. |
| Lien Release | A written document from the contractor to the owner that releases the Lien (mechanic’s or material) following its satisfaction. |
| Lien Waiver | A written document from a contractor or material supplier having lien rights against an owner’s property that relinquishes all or part of those rights. |
| Lifting Flame | See Floating Flame |
| Length | A unit of linear measure for pipes, such as 10 or 20 ft. |
| Life Cycle Labs | A place where water heaters are tested at an accelerated rate to simulate life expectancies. |
| Light Duty | Small commercial applications. |
| Lime | See sediment. |
| Limit Stop | Faucet control unit used to adjust maximum water temperature. |
| Lock Nut | Nut fitted into a piece of pipe and screwed onto another pipe to join the two pieces. |
| Low Consumption Toilet | A class of toilet designed to flush using 1.6 gallons of water or less. Also known as ”Water-saving” toilets. |
| M Tubing | An industry standard for copper tubing defined by the tube wall thickness, identified by a ”red” stripe |
| MC Tank | Acetylene tank holding 10 cu.ft. of gas, used for plumbing, once used to fuel motorcycles. |
| MCL | Maximum Contaminant Level The maximum level of a contaminant allowed in water by federal law. Based on health effects and currently available treatment methods. |
| MHT | Male Hose Threads (threads on outside of connection). |
| MIPC | Male Iron Pipe Connection. Standard external threads on pipe and fittings. |
| MNPT | Refers to the male pipe thread, in which the threads are on the outer side on the connection fitting. |
| MPN | See Most Probable Number. |
| MPX | Male Pipe Swivel Connection. |
| Macerator | A device installed in a drain line between a toilet and the soil stack to reduce solids to liquid form. |
| 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. |
| Main | The primary artery of supply of the water supply or drain system in which all the branches connect. In the case of drains, known as the Main Vent. |
| Male Fitting | Fitting that is inserted into another fitting. |
| Male Threads | Threads on the outside of pipes and fittings. |
| Malleable Fittings | Fittings made of cast iron. Metal which is soft and pliable. |
| Manganese | An element sometimes found dissolved in ground water, usually with dissolved iron but in lower concentration; causes black stains and other problems similar to iron. It can be removed by a water softener or it can be precipitated by chlorine at a pH of 9.5 or above. |
| Manganese Greensand | Greensand that has been processed to incorporate in its pores and on its surface the higher oxides of manganese. The product has a mild oxidizing power, and is often used in the oxidation and precipitation of iron, manganese and/or hydrogen sulfide, and in their removal from water. |
| 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). |
| Manifold | A fitting that connects a number of branches to the main; serves as a distribution point. |
| Manifold Pressure | The gas pressure in an appliance manifold upstream of the burner orifices. |
| Manifolded Installation | Paralleling of water heaters for large hot water demand applications. |
| Mapp Gas | A colorless, flammable gas made by combining liquified petroleum gas with Methylacetylene-Propadiene. It is a stable, non-toxic fuel used in brazing and soldering. |
| Mechanic’s Lien | A lien obtained by an unpaid subcontractor or supplier through the courts. When enforced, real property – such as your home – can be sold to pay the subcontractor or supplier |
| Mechanical Controls | Dials, slides, switches, knobs, buttons, and so forth used to operate ranges, ovens and cook-tops. |
| Mechanicals | The wiring, plumbing and heating and cooling systems in a building; also the components with moving parts such as furnaces, plumbing fixtures, etc. |
| Metal fatigue | A breakage of the metal caused by the bending and flexing or the expansion and contraction of a metal part beyond its endurance limit. |
| Meter Tailpiece | An adapter connecting a water meter to the water supply line. |
| Meter Tile | The cylindrically shaped casing that forms the pit to hold a water meter. It’s usually made of plastic. |
| Micron | A unit of measure, one thousandth of a meter. Used to describe the pore size of filters. |
| Millivolt | One thousandth of a volt. |
| Mini-Widespread | A special style of bathroom lav faucet having separate spout and handles, but small enough to fit 4 inch center-to-center faucet holes. |
| Minimum Run Time | The minimum length of time that the pump should run while refilling the pressure tank. |
| Mission Coupling | A neoprene flex coupling, connecting pvc to pvc or clay to pvc. |
| Mixer | The portion of a burner where air and gas are mixed before delivery to the burner ports. |
| Mixing Valve | Mixes hot and cold water to achieve a specified delivery temperature. |
| Moenstone | A blend of ceramic-like quartz (70%) and acrylic polymer (30%) that is impervious to chips or water spots. |
| Monitor Cover | The cast iron lid that fits over a flange casting which is mounted on meter tile in a water meter pit. It consists of an outer lid, an inner lid, and the flange casting in one or two pieces. |
| Monobloc Faucet | A single-handle faucet, usually a lever. |
| Most Probable Number | Most Probable Number (MPN) The term used to indicate the number of organisms which, according to statistical theory, would be most likely to produce the results observed in certain bacteriological tests; usually expressed as a number in 100 ml of water |
| Multi-Port Valve | Rotary type backwash valve. Can replace up to 6 regular gate valves. Serves various functions. |
| Multi-Stage Pump | A pump that has more than one impeller. |
| Municipal Water | Water supplied by a city for public use; tap water. Usually held in a reservoir. |
| NEMA | National Electrical Manufacturers Association |
| NH | No Hub |
| NKBA | National Kitchen and Bath Association |
| NOM | Nominal. Usually refers to the Inside diameter of trade sizes of copper pipe and some CPVC pipes. Not for Iron Pipe connections. For example, a 1/2” NOM Comp. Fitting is actually 5/8” because 1/2” pipe has an OD of 5/8”. |
| NPS | National Pipe Straight threads standard, Same as IPS |
| NPSP (Discharge) | Non Point Source Pollution. Nutrients, sediments, toxic substances, and pathogens that degrade waterways. NPS occurs mainly through stormwater runoff. |
| NPSHA | Net Positive Suction Head Available to prevent cavitation of the pump. It is defined as: Atmospheric pressure + gage pressure + static pressure – vapor pressure – friction loss in the suction piping. |
| NPSHR | Net Positive Suction Head Required to stop a pump from cavitating. This number is provided by the pump manufacturer. |
| NPT | National Pipe Tapered thread standard. The same as IPS. |
| NSF | National Sanitation Foundation |
| 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. |
| Negative Pressure | Less than atmospheric pressure. |
| Net Usable BTU | That portion of a fuel’s heat energy actually transferred into the water by a heater. |
| Nipple | A short length of pipe installed between couplings or other fittings. |
| Nipple Extractor | A tool used to unscrew sections of pipe. |
| No-Hub Connector | A connector for no-hub iron pipe consisting of a rubber sleeve and a stainless steel band secured by hose clamps. A variation, a neoprene sleeve with two adjustable steel bands, is used for connecting dissimilar materials, as when connecting new plastic pipe to an existing cast-iron drainpipe |
| Non-CFC Foam | Insulation that minimizes the use of Chlorofluorocarbons. |
| Non-Ferrous | Not containing iron. |
| Non-Potable | Not suitable for drinking. |
| O-Ring | Round rubber washer used to create a watertight seal, chiefly around valve stems. |
| OD | Outside Diameter |
| OEM | Original Equipment Manufacturer. |
| Oakum | Loosely woven hemp rope that has been treated with oil or other waterproofing agent; it is used to caulk joints in a bell and spigot pipe and fittings. |
| Oil Powered | A water heater that uses oil as its fuel source. |
| One-Piece Toilet | A toilet in which the tank and bowl are manufactured as a single vitreous china fixture. One-piece toilets usually have a lower profile than two-piece toilets. |
| Operating Cost | The cost of running a water heater for a given time period. |
| Orbital Weld | A circumferential, full fusion weld used to join together two lengths of tubing. It is a GTAW welding process. Usually to join coiled lengths. |
| Organic Matter | Plant and animal residues, or substances made by living organisms. |
| Orifice | An opening through which gas is discharged and whereby the flow of gas is limited and/or controlled. |
| Outlet / Discharge | The opening through which the water exits the pump. |
| Outlet Sewer | Pipe section in a septic system which runs between the septic tank and the drainage field. |
| Outside Diameter | The diameter of a pipe measured from the outside edge. (OD) |
| Overflow Tube | Overflow hood On a bath drain, the decorative hood concealing the overflow. 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. |
| Ozone | An unstable form of oxygen (O3 ), which can be generated by an electrical discharge through air or regular oxygen. It is a strong oxidizing agent and has been used in water conditioning as a disinfectant. |
| P Trap | See Trap |
| P & T Relief Valve | Pressure and Temperature Relief Valve – Same as T & P |
| PB | Polybutylene. A flexible plastic tubing used in water supply systems where allowed by code. Also, polished brass finish on faucets. |
| PDI | Plumbing and Drainage Institute |
| PE | Polyethylene plastic material. Also Plain End pipe. |
| PEX | Cross-linked polyethylene. PEX tubing is commonly used for hydronic radiant floor heat, but increasingly also used for water supply lines. Stronger than PE. |
| PH | Potential Hydrogen. The hydrogen ion concentration of water to denote acidity or alkalinity, measured on a scale of 0 to 14. Below 7 denotes acidity; above 7 denotes alkalinity. |
| PHCCA | Plumbing Heating Cooling Contractors Association |
| P O Plug | Lavatory drain with separate removable plug |
| PoS | Porcelain on Steel. A finish commonly used on sinks and tubs. |
| PP | Polypropylene Pipe. |
| PPM | Parts Per Million. A unit of measure for impurities in water. |
| PR | Pressure Regulator. Usually required if water pressure ever exceeds 80 PSI on potable water supplies inside a structure. |
| PSI | Pounds per Square Inch |
| PSIG | Pounds per Square Inch Gauge. |
| PVC | Polyvinyl Chloride. A rigid white or cream-colored plastic pipe used in non-pressure systems, such as drainage, waste, and vent systems. |
| PVD | Physical Vapor Deposition. A modern plating process used mostly with polished brass or gold finishes on faucets. Vaporized zirconium reacts with nitrogen and other gases to form a very durable surface, which will not tarnish or discolor. |
| Packing | Fibrous material that is used on faucets to prevent leaks. |
| Packing Nut | The nut that holds the stem of a faucet in position & holds the packing material. |
| Parallel System | Two or more identical size heaters piped with water connections, that is, cold water travels equal distance into the inlets of the heaters from a ”T” connection and hot water travels equal distance from the outlet of the heaters to a ”T” connection. |
| Peak Hour Demand | Time when the largest demand for hot water is needed. |
| Peak Load Period | The period of the day in which the system has the greatest demand. |
| Penal Valve | A commercial flush valve, so-named because of its use in penal institutions. |
| Perfect Vacuum | Theoretically, space without matter in it. A perfect vacuum has never been obtained. |
| Perforated Pipe | Pipe designed to discharge water through small, multiple, closely spaced orifices or nozzles, placed in a segment of its circumference for irrigation purposes |
| Petcock | A small faucet for draining liquids or relieving air pressure. |
| Phase | For ease of production and distribution, A.C. is distributed in what is known as a 3 phase supply using three active wires and one neutral wire. |
| Phenol | A poisonous and carcinogenic chemical often found in municipal water supplies. Also known as carbolic acid, phenol is a benzene derivative. |
| Pickling | Pipe immersed into acid bath for removal of scale, oil, dirt, etc. |
| Piezo Switch | The electronic switch the bather uses to control the whirlpool and optional heater. This switch, based upon the piezo-electric effect, generates a voltage when pressure is applied to it. |
| Pilot | A small burner used to ignite the main burner. |
| Pin | External (male) threaded end of pipe. |
| Pipe Dope | Industry term for pipe-joint compound. Substance applied to threaded fittings to create a watertight seal. |
| Pitch | Downward slope of a drain pipe in the direction of the water flow. |
| Plug | Male threaded fitting which seals the end run of a pipe when fitted into a female threaded fitting. |
| Pivot Door | A shower door that rotates on two metal pivots at the top and bottom of the door. |
| Plumb | Precisely vertical. Also to test for, or to make vertical. Also to perform plumbing work. |
| Plumber’s Helper | A plunger |
| Plumber’s Putty | Pliable putty used to seal joints between drain pieces and fixture surfaces. |
| Plumbing Tree | Prefabricated set of drain waste, vent, and supply lines. |
| Pneumatic | Pertains to devices using compressed air. |
| Point of Use | Small water heater used for remote locations. |
| Pop-up Assembly | The drain mechanism of a faucet installed on a lavatory. The drain stopper ”pops” up and down. |
| Pop-up Drain | Type of drain assembly for lavatory and bath. When a lavatory lift rod or bath overflow plate lever is lifted, the pop-up drain closes so the lavatory or tub retains water. |
| Poppet | Valve that rises perpendicularly to or from its seat. |
| Porcelain | White ceramic ware that consists of quartz, kaolin, and feldspar. It is fired at high temperature on steel or cast iron to make the surface of some bathtubs, kitchen sinks, and bathroom lavatories. |
| Porcelain Enamel | Vitreous enamel. Often refers to pressed steel products with a porcelain glaze. |
| Porosity | A measure of the volume of internal pores, or voids, in ion exchangers and filter media; sometimes expressed as a ratio to the total volume of the medium. |
| Port | An opening in a burner head through which gas or an air-gas mixture is discharged for ignition. |
| Positive Displacement Pump | Known as a ”PD pump.” Gear, sliding vane, progressive cavity, lobe etc. the capacity determined by the pump speed. The maximum head is determined by the horsepower available and the casing strength. |
| Potable Water | Water that is suitable for drinking. |
| Potentiometer | An adjustable resistor used to vary the sensing distance of the touch-less faucet. |
| Powder-Coat | A technique for applying paint to aluminum shower door frames. The aluminum is covered with a powder of dry paint particles and is baked in an oven. This causes the powder to melt and harden into a tough, colorful finish. |
| 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 water-logging. This tank design provides greater draw-down than standard tanks. Pre-charged tanks do not require air volume control. |
| Pre-Heated Water | Water that has been tempered (heated) for inlet supply. |
| Pressure Balanced Valve | A 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 called an anti-scald valve. |
| Pressure Head | Pressure in a plumbing system. The unit of measure which is the vertical force exerted by water at a depth of one foot. |
| Pressure Loss | The term given for the loss of pressure that occurs whenever water moves through a pipe or when water moves uphill against the force of gravity. If the total pressure loss in a piping system exceeds the available static water pressure the water will not flow. |
| 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. |
| Pressure Tubing | Tubing used to conduct fluids under pressure or at elevated temperatures or both, and produced to stricter tolerances than pipe. |
| Primary Air | Air which is mixed with gas before the gas leaves a burner port to burn. Ideal burning condition generally is 10 cubic feet of air per one cubic foot of gas. |
| Primary Air Inlet | The opening(s) through which primary air is admitted into a burner. |
| Priming Jet | Opening in bowl through which tank-supplied water flows, designed to propel waste up into the trapway. |
| Pull-out Spray | Single-control kitchen faucet which offers a retractable hose and spray-head to be used for food preparation and cleaning. |
| Public Sewer | A common sewer directly controlled by public authority. |
| Pumping Level | The lowest water level reached during pumping operation. |
| Purged Line | A plumbing line in which the faucet has been opened and allowed to run for a specified length of time, usually1-5 minutes. |
| R & D | Reamed and Drifted. Pipe commonly used in water wells having a special, heavy-duty coupling and a guaranteed I.D. clearance. |
| RF | Recovery Factor – Rating based on the efficiency of the product which is input required to raise 1 gallon of water 1 degree Fahrenheit. |
| Rail Fittings | Fittings with setscrews rather than threads, which hold pipes used for hand railings. Available in various sizes and configurations to suit a number of applications. Not used for plumbing or conduit. |
| Rated Storage | Volume Quantity of water stored in a tank. |
| Raw Water | Water supplied to the plant before any treatment. |
| Reamer | A grinding tool used to level or remove burrs from valve seats in faucets so that the valve stem will fit properly. |
| Recessed Tub | A tub that has a decorative finish on one side only, and surrounded by three walls. The apron, or skirting, may not be included and must be ordered separately. The most popular style. |
| Recirculating Harness | PVC tubing setup that circulates water throughout a whirlpool system, delivering water to the jets. |
| Recovery | The amount of water in gallons that can be heated in one hour. (gph). |
| Recovery Capacity | The amount of water in gallons per hour raised 100 degrees F at a given thermal efficiency and BTU per hour input. |
| Red Water | Water which has a reddish or brownish appearance due to the presence of precipitated iron and/or iron bacteria. |
| Reducer | A fitting that connects pipes of different sizes together. |
| Reed Switch | A serviceable, magnetic sensing switch that triggers the water flow to stop when the neck jet pillow (with magnet) is removed from the whirlpool. |
| Refill Tube | The tube that directs water from a ballcock into the overflow tube to refill the bowl after a siphon break. |
| Relief Valve | A valve that opens to relieve excess temperature. |
| Repair Clamp | Sleeve type clamp used to repair a split pipe, held in place by bolts. |
| Return Circulation System | Tempered water from or near the point of usage which eliminates waste of hot water used for long runs and adds storage to the system. |
| Revent | Pipe installed specifically to vent a fixture trap. Connects with the vent system above the fixture. |
| Reverse Osmosis | A water treatment method whereby water is forced through a semi permeable membrane which filters out impurities. |
| Reverse Trap Water Closet | A water closet having a siphonic trapway at the rear of the bowl, and integral flushing rim and jet. Min. dimensions are 9” x 8” water spot and 1-1/” ball pass. |
| Rigid Pipe | Pipe designed to transmit the backfill load to the foundation beneath the pipe. Rigid pipe must be supported on the bottom portion of the pipe |
| Rim Holes | A series of small holes in the underside of a toilet rim, around the circumference of the bowl. Incoming water flows down into the bowl through these holes, creating a rinse effect or wash over the entire inner surface of the bowl. |
| Riser | A vertical metal or plastic tube or assembly that connects a faucet to the water supply stop valve. Usually made of copper. Metal Flex Risers are corrugated to facilitate bending. Also a supply line that rises from one story to the next. |
| Residual Chlorine | Chlorine Chlorine remaining in treated water after a specified period of contact time to provide continuing protection throughout a distribution system; the difference between the total chlorine added, and that consumed by oxidizable matter. |
| Roller Hanger | A pipe hanger similar to a clevis hanger except that the yoke bolts to a roller rod instead of a metal strap. This roller rod supports the pipe and permits horizontal movement. |
| Roman Spout | Deck-mounted faucet spout. |
| Roof Drain | A drain installed at the low spot in a roof that channels water into a drainpipe to prevent pooling. |
| Roof Flashing | Sheet metal installed at any break in a shingled roofline to prevent leaks. Also around sewer vents, fluepipes. |
| Root Valve | A multi-port valve commonly used on gauges or switches in high pressure, high temperature, or under otherwise severe process conditions. Typically built with non-rotating and non-threaded stems. |
| Rough-In | Installation of the drain, waste, vent, and supply lines in a structure to the proposed location of each fixture. |
| Rough-In Dimensions | The distance from a finished wall or floor to the center of the waste or supply opening or mounting holes on a plumbing fixture. |
| Round Front Bowl | Standard shape of the front of a toilet bow, having dimensions of 14” wide by 16-1/2” long from center of seat hinge holes to front outside rim edge. |
| Run | A complete or secondary section of pipe that extends from supply to fixture or drain to stack. |
| Running Trap | An in-line trap mounted in a horizontal drainpipe, where the inlet and outlet are parallel. |
| SAE | Society of Automotive Engineers standard; a thread size used on nuts and bolts but not pipe connections. |
| SJ | Slip Joint. |
| SMLS | Seamless pipe. |
| SN | Satin Nickel finish. |
| SS | Stainless Steel. |
| STD | Standard |
| SV | Service Victory. A designation for service weight cast iron drainage pipe. |
| Saddle Tee | Fitting that taps into the side of a pipe, used to make quick connection to an existing line. |
| Saddle Valve | A valve mounted on a pipe run by a clamping device, or saddle tee to provide a water supply for a low-demand device. |
| Safe Drinking Water Act | An amendment to the Public Health Service Act, which was passed in 1976 to protect public health by establishing uniform drinking water standards for the nation. In 1986 SDWA Amendments were passed that mandated the EPA establish standards for 83 drinking water contaminants by 1992 and identify an additional 25 contaminants for regulation every 3 years thereafter. |
| Safety Shutoff Valve | A device on a gas appliance that shuts off the gas supply to prevent a hazardous situation. A flame safety shutoff operates when the actuating flame becomes extinguished. |
| Sag Pipe | A section of a sewer line that is placed deeper in the ground than normal in order to pass under utility piping, waterways, rail lines, highways, or other obstacles. The sewer line is raised again after passing under the obstacle. |
| Sanitary Fitting | Fitting that joins the assorted pipes in a drain, waste, and vent system, designed to allow solid material to pass through without clogging. |
| Saponification | The process in which a fatty acid is neutralized with an alkali or base to form a soap. |
| Sanitary Sewer | House drain that carries wastewater away from the house to a sewer system or septic tank. |
| Scale | A thin coating or layer, usually calcium on the bottom of a tank or interior parts that may prevent heat transfer. |
| Schedule | Numbers assigned to different wall thicknesses of pipe (e.g. sch 40). |
| Scupper Drain | A drain normally located on a roof or deck that allows rain water to drain off. |
| Seal-Off Fitting | Fitting which prevents gas leakage from moving from one section of pipe to another. |
| Sealed Combustion | Sealing of combustion chamber to prevent spillage of combustion products. |
| Sealed Combustion Heater | A heater which pulls combustion air from outside the structure and vents combustion by-products to the outside. |
| Seamless Pipe | Pipe with no weld in the circumference. |
| Secondary Air | The remaining air needed for complete combustion besides primary air. This is the air surrounding the flames outside the burner ports. |
| Sediment | The substance that settles on the bottom of a water tank. Also known as lime. |
| Self-Rimming Sink | Sink with no metal ring that has a built-in lip of the same material which supports it in the vanity top. |
| Sequestering Agent | A chemical compound sometimes fed into water to tie up undesirable ions, keep them in solution, and reduce their effects. For example, polyphosphate can sequester hardness and prevent reactions with soap. |
| Series System | System where a primary heater preheats water to a given desired general purpose temperature and feeds into another heater. |
| Self-Rimming | A style of bathroom sink with a rolled and finished edge. |
| Serial / Model / Rating Plate | A permanent information plate attached to major home appliances. The plate includes product model and serial numbers, plus information about wattage or BTU requirements. |
| Service Entrance | Pipe connecting the water company piping to the water meter. |
| Service Pressure | The range of pressure in the pressure tank during the pumping cycle, usually expressed in pounds per square inch gauge (P.S.I.G.). |
| Service Sink | Deep fixed basin, supplied with hot and cold water, which is used for rinsing of mops, disposal of cleaning water, or washing clothes and other household items. |
| Service Tee | Tee fitting with male threads on one run opening and female threads on the other two. |
| Sewer Ejector | See Ejector. |
| Sewer Gas | Gases, esp. methane, which may be combustible and poisonous from the decay of organic materials in the sewer system. |
| Shallow Well | A well with a pumping head of 25 feet or less, permitting use of a suction pump. |
| Shroud | Color-matched component under a wall-mount lavatory that covers the drain outlet for aesthetic purposes. |
| Shower Receptor | A one-piece base (floor) unit used as a shower, for example, to catch water and direct it to a center drain. |
| Shutoff Valve | Usually refers to angle stops installed under sinks and toilets, but also valves installed on branch lines and alongside the meter. |
| Side Cutter | A heavy duty auger tip for large diameter pipes. |
| Sight Hole | Generally a window on oil-fired products that allows the viewing of burner and flame patterns. |
| Sillcock | See Hose Bibb |
| Simplex Basin | An ejector pump container usually 18” x 30” for single family homes. Single Threshold Type of shower base used in a three wall installation with the threshold being the side with the door. |
| Siphon | A pipe connecting two canals. A tube or pipe through which water flows over a high point by gravity. |
| Siphon Break | The point in a toilet flush cycle when air is re-introduced into the trapway, breaking the siphonic action. This is characterized by the deep gurgling sound heard at the end of a flush. |
| Siphon-Jet Water Closet | A toilet having a siphonic trapway at the rear of the bowl and an integral flushing rim and jet. |
| Siphon-Vortex Water Closet | A toilet having a trapway at the rear of the bowl integral flushing rim and a water supply system with or without a jet, which does not feed directly into the trap. |
| Siphon Wash Closet | A toilet having a trapway at the rear of the bowl and integral flushing rim, and minimum dimensions of 5” x 4” water spot and 1-1/2” ball pass. |
| Siphoning | The suction or pulling effect that takes place in the trapway of a toilet as it is filled with outgoing water and waste. |
| Sisson Joint | This is a joint between pipes that is larger on one end than the other. NOTE: Sisson joints are often prohibited for drainage system purposes. |
| Sleeve | Pipe which is passed through a wall for the purpose of inserting another pipe through it. |
| Slide Bar | Type of shower component designed for the attachment of a hand-shower. The mounting bracket can be adjusted at different heights to accommodate individual preference. |
| Sliding Inner Door | A door that slides along the combustion chamber radius for easy access to the burner and pilot. |
| Slip Gasket | Elastomer (natural occurring elastic substance) gasket, usable with a hub and spigot pipe because it has a tapered cross section. |
| Slip Joint | A connection made with compression fittings. |
| Soda Ash | Common name for sodium carbonate, Na2CO3 a chemical compound used sometimes used in soap and detergents to neutralize acid water. |
| Soft Flame | A flame partially deprived of primary air such that the combustion zone is extended and the inner cone of the flame is ill-defined. |
| Soft Water | Water that has a low calcium and magnesium content. |
| Soil Cutter | A device used to cut No Hub pipe, consisting of a handle and a cutting chain, similar to a chain wrench in appearance. |
| Soil Pipe | A sewer pipe for carrying off waste from toilets. |
| Soil Stack | Largest vertical drain line to which all branch waste lines connect. This line carries waste to the sewer line. |
| Solder | A metal alloy that is melted to create a fused joint between metal pieces. Also the act of melting solder into the joint. |
| Solute | The substance which is dissolved in and by a solvent. Dissolved solids, such as the minerals found in water, are solutes. |
| Solvent Weld | Any of the types of PVC pipe and fittings that are fastened together with solvent-based cement. |
| Spark Ignition | Intermittent ignition devices that utilizes a spark to light a flame. |
| Spark Test | A test procedure to evaluate the integrity of the glass lining. |
| Specific Gravity | The ratio of the weight of a specific volume of a substance compared to the weight of the same volume of pure water at 4oC. |
| Specific Heat | Amount of heat required to raise the temperature of a kilogram of a substance one degree Celsius. |
| Spigot | The plain end of a cast-iron pipe. The spigot is inserted into the bell end of the next pipe to make a water tight joint. |
| Spigot Soil Adapter | Hub adapter to connect PVC with soil pipe. |
| Spline Adapter | Device sometimes required to form a mating connection between the splines of a valve stem and the splines inside a faucet handle. |
| Spud | A threaded opening on the water heater tank. Also a tool for digging having characteristics of a shade and chisel. |
| Stack | The vertical main in the drain, waste, and vent system, extending one or more stories. |
| Stacking | The ability of hot water to form layers of different temperatures in the tank stratification. |
| Stainless Steel Sink | Steel sinks made of solid stainless material, durable, and immune to rust and corrosion. The gauge measures the thickness of the steel, with a lower number indicating thicker steel. Their underside is often sprayed with a rubberized undercoating to provide a sound-deadening barrier, eliminate condensation, and reduce heat transfer. |
| Stand Pipe | Open vertical pipe that receives water from a washing machine. Also the vertical pipe run supplying water to a fire sprinkler system; also large vertical pipe into which water is pumped in order to produce a desired pressure; a high vertical pipe or reservoir that is used to secure a uniform pressure in a water-supply system |
| Standing Pilot | See Pilot |
| Static Discharge Head | The vertical distance from the pump to the highest outlet in the water system Stand By Loss. The amount of heat lost while a unit is in stand by mode. |
| Static Lift | The vertical distance between source and discharge water levels in a pump installation. |
| Static Pressure | The pressure when no water is flowing. |
| Static Water Level | The undisturbed level of water in the well before pumping. |
| Stem | Part of the faucet that holds the handle on one end and the washer on the other. Stiffener A galvanized bushing used to strengthen tubing to fit in a leadpak coupling. |
| Stillson Wrench | Pipe wrench |
| Stop | The shutoff valve under sinks and toilets. Allows water supply to be cut off to one fixture without affecting the water supply to other fixtures. |
| Stop and Drain Fitting | Plug-type valve used to tap into a water main to control the flow to a branch line, which has a side opening to shut off the water and allow it to drain out so the pipe won’t freeze. |
| Storage Tank | A tank used to hold a specific volume of water. |
| Storm Drain | Drain used to receive and convey rain water, surface water, and ground water away from buildings. |
| Straight Cross | Fitting that connects four pipes of the same diameter. |
| Straight Pipe Threads | A special kind of straight thread used only on iron pipe, toilet, and faucet fittings. A cone seal or gasket is usually included because straight threads will not form a complete seal without a gasket of some kind. |
| Straight Stop | An emergency stop valve that is usually installed before the water supply line to toilets and faucets. Similar to angle stops but the line does not change direction. |
| Strainer Pot | A housing on the influent side of a pump that serves as a priming chamber and a receptacle for the strainer basket. |
| Strap Wrench | Tool with metal body and heavy cloth or metal mesh belt used for turning pipe. |
| Street Ell | A 90 degree elbow joint with a hub on one end and male threads on the other. Used to make an angled connection between pipe or tubing and a fitting with a hub. |
| Stub-Out | Short lengths of pipe installed during rough-in to which fixtures and drains will eventually be installed. |
| Stud Guard | Short band of metal attached to wall studs to prevent nails from penetrating and damaging pipes |
| Stuffing Box | That portion of the pump that held the packing and now holds the mechanical seal. |
| Submergence | The distance the ejector, foot valve or submersible pump is installed below the pumping level. |
| Suction Head | The head on the suction side of the pump. This is subtracted from the discharge head to determine the head being produced by the pump. It is a sum of the static, pressure and friction heads. |
| Suction Static Lift | Same as Suction Static head. This term is only used when the pump centerline is above the suction tank fluid surface. |
| 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. |
| Supply Kit | Usually a kit of all parts needed to connect a faucet or toilet to the pipes coming out of the wall. Usually includes stop valves, water connectors, and escutcheons. |
| Supply Stop | The valve controlling water supply to a toilet. |
| Surface Mount | Typically refers to thermostats mounted on the outside of the tank that senses temperature through the steel tank. |
| Surface Pump | A mechanism for removing water or wastewater from a sump or wet well. |
| Suspended Solids | Solid particles in water which are not in solution. |
| Sweating | Term for soldering. Also formation of condensation on the outside of pipes or toilet tanks. |
| Sweep | A drain ell fitting with a long radius that allows for smooth passage of waste. Fittings with abrupt changes of direction, such as a vent tee, may only be used for vents. |
| Swing Joint | A flexible sprinkler connection made by connecting three threaded elbows fittings together. |
| TBE | Threaded Both Ends |
| T & C | Threaded and Coupled. Some cast iron pipe is sold threaded with a coupling attached. |
| TDS | Total Dissolved Solids. |
| TO | Threads Only. |
| T & P Valve | Temperature & Pressure relief valve. A safety device used to expel excess pressure or heat from inside a tank. |
| TPI | Threads Per Inch |
| T & S | Tub and Shower |
| Tailpiece | Section of pipe that runs between a fixture outlet and the trap. |
| Tail Pipe | The pipe added below the jet assembly, in a weak well application. |
| Tank Fixture | A reservoir for flush water. On a conventional toilet, the ballcock, flush valve, and trip lever are installed in the tank. A tank lid closes the top tank opening. |
| Tank Cross | A double-tee-shaped fitting installed between a shallow well pump and the bladder tank with integrated valve and gauge fittings, and an outlet for a pressure-relief valve. |
| Tank-less Water Heater | Instantaneous water heater. |
| Tannin (Tannic acid) | A substance occurring naturally in well water. It is produced by decaying vegetation, and causes the water to have a yellow of light brown color and can provide a bitter taste. There is currently no EPA regulatory level for tannin in water. |
| Tap Adapter | Fitting with one plain end and one threaded female end. |
| Tap Tee | Cast iron tee with a threaded female side inlet. |
| Tap Water | Water provided by a water company by way of the home’s plumbing system. |
| Tapered Pipe | Standard type of threads used on iron pipe and pipe fittings. |
| Tee | T-shaped fitting with three openings that allow another pipe to be joined at a 90 degree angle, used to create branch lines. |
| Teflon Tape | A fluorocarbon polymer with non-sticking properties used to wrap pipe threads to seal a joint. |
| Temperature Rise | The number of degrees Fahrenheit that incoming water must be raised to reach the desired water temperature. |
| Tempered Glass | Glass that has been annealed or strengthened by a process of gradually healing and cooling. Once a piece of glass has been tempered, it cannot be cut. If it breaks, it breaks into many small pieces. By code, all shower doors must be made of tempered glass. |
| Tempering Valve | An in-line hot / cold mixing valve. |
| Test Plug | A rubber plug that is used to seal off sections of pipe to allow testing for leakage. |
| Test Tee | A tee with a removable plug for permitting access to a drainage line. |
| Therm | Measurement of 100,000 BTU’s. |
| Thermal Efficiency | Ability to transfer and absorb heat from fuel sources into the water. |
| Thermal Expansion | The effect of water expanding when heated. |
| Thermal Stratification | See Stacking. |
| 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 that automatically maintains a predetermined temperature in an appliance. |
| Thermostat (Upper) | Device that 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. |
| Throat-Plate | The underside portion of some faucet spouts which also use a top shroud to cover an assembled faucet waterway. The throat-plate is only visible when viewed from a very low angle. |
| Threaded | A helical or spiral ridge on a screw, nut, or bolt. |
| Tile Rise (Buttress) | The raised portion of a shower curb that is on more than one level. |
| Total Dissolved Solids | A measure of the total amount of dissolved matter in water. |
| Total Head | The difference between the head at the discharge and suction flange of the pump ( syn Total Dynamic Head, pump head, system head). |
| Touchless Faucet | Commercially installed faucet or urinal valve that function using infrared sensor system. |
| Total Discharge Head | The total pressure or head the pump must develop. It is the sum of the depth to pumping level, elevation, service pressure, and friction loss. |
| Toxicity Test | Test to determine the toxicity of a chemical or an effluent using living organisms. It measures the degree of response of an exposed test organism to a specified chemical or effluent. |
| Transite Pipe | Pipe manufactured from asbestos and concrete, commonly found in water mains. Transom Panel a panel usually located above the door of an enclosure. It can be used to keep steam inside of a steam-shower unit. Some open to vent steam. |
| 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. |
| Trap Arm | The waste arm portion of a drainage trap. |
| Trap Dip | The U-bend portion of a drainage trap. |
| Trap Drain | A flex adapter to connect 1-1/2” to 1-1/2” drain pipe Trap Primer A small feeder line connecting the cold water line directly to the drainage trap, which releases a small amount of water to the trap should it run dry to maintain the water seal. |
| Trap Seal | Height of water in a toilet bowl ”at rest.”. It provides the water seal which prevents sewer gases from entering the home. It is measured from the top of the dam down to the inlet of the trapway. Also referred to as deep seal. |
| Trap Weir | See Crown Weir. An interior projection in the outlet side of a trap to aid in maintaining a water seal. |
| Trapway | Channel in a toilet that connects the bowl to the waste outlet. It is where the siphonic action takes place. The trapway is measured in terms of the largest diameter ball which can pass through it. Also called the passageway. Trim Any non-vitreous china toilet components, except the seat. Includes such items as ballcock, bolt caps, trip lever. |
| Trenchless | A system of installing or replacing underground infrastructure by pulling the lines through an existing pipe or a pilot hole, rather than laying pipe into long, pre-dug trenhches. More on Trenchless Services. |
| 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. Tube Talon Plastic hanger for mounting copper pipe. |
| Tube Valve | A valve which is opened or closed by mechanically moving a tube upstream or downstream by an actuating screw Tube Washer Replacement washer for one end of a closet tube. |
| Tuberculation | The process in which blister-like growths of metal oxides develop in pipes as a result of the corrosion of the pipe metal. Iron oxide tubercles often develop over pits in iron or steel pipe, and can seriously restrict the flow of water. |
| Turbulent Flow | Fluid flow in which the velocity at a given point varies erratically in magnitude and direction. Turbidity Water cloudiness caused by suspended particles. |
| Two-Piece Toilet | Toilet with a separate tank and bowl. Also referred to as a close-coupled toilet. Type ”L” Tube An industry standard for copper tubing defined by the tube wall thickness and identified by a ”blue” strip. Type ”L” copper tube wall is approximately 50% greater thickness than Type ”M.” |
| Type ‘M’ Tube | An industry standard for copper tubing defined by the tube wall thickness and identified by a ”red” stripe Tyseal Gasket Gasket for joining SV cast iron pipe into a hub. |
| UL | Underwriters Laboratories |
| ULF | Ultra Low Flush. Widely used description of 1.6 gpf or less toilets. |
| UNC | Unified National Coarse Thread. A standard kind of coarse straight thread used on fittings, nuts, and bolts. Not for pipes. |
| UNF | Unified National Fine Thread. A standard kind of fine straight thread used on fittings, buts, and bolts. Not for pipes. |
| USEPA | United States Environmental Protection Agency |
| USPHS | United States Public Health Service |
| Ultracoil | True double wall heat exchanger. |
| Uni-flex | One piece stop and riser combination. One-piece supply. |
| Uniformity Coefficient | A measure of the variation in particle sizes of ion exchange resins and filter media. It is defined as the ratio of the size of particle that has 60 percent of the material finer than itself, to the size of the particle that has 10 percent finer than itself. |
| Union | Three piece fitting that joins two sections of pipe, but allows them to be disconnected without cutting the pipe. Used primarily with steel pipe; never in a DWV system. |
| Universal Plumbing Code | A system of procedures designed to provide consumers with safe and sanitary plumbing systems and used throughout the United States by local jurisdictions. |
| Urinal | A plumbing fixture which receives only liquid body waste and conveys the waste through a trap seal into a gravity drainage system. |
| Urinal Strainers | Refers to a domed metal piece fastened to the bottom of an urinal to prevent debris from plugging the trapway of the unit. |
| Usable Storage | Percentage of hot water that can be drawn from a tank before the temperature drops to a point that it is no longer considered hot. |
| Utility Sink | Deep fixed basin, supplied with hot and cold water, which is used for rinsing of mops, disposal of cleaning water. |
| V-clip | A clip shaped like the letter ”V” used on a lavatory drain lift linkage assembly to easily adjust connection of the drain to the lift rod. |
| Vacuum Breaker | An anti-siphon device that prevents the backflow of contaminated water into the water supply system. |
| Valve | A device that regulates the flow of fluid. |
| Valve Dressing | Resurfacing a worn valve seat with a special tool. Stops leaks by providing a smooth sealing surface. Applies only to older compression style faucets. |
| Valve Seat | The non-moving part of a valve. Water flow is stopped when the moveable portion of the valve comes in contact with the valve seat. |
| Valve Seat Wrench | Hexagonal end wrench inserted into the hexagonal opening in a valve seat for installing or removal. |
| Vanity | A bathroom storage cabinet under the wash basin. |
| Velocity Head | The amount of energy required to accelerate water to a given velocity; expressed in feet per head. |
| Vent | A pipe that allows air into a drain system to balance the air pressure, preventing water in the traps from being siphoned off. |
| Vent Header | A vent pipe into which several vents connect. The vent pipe leads to the vent stack and out of the building. |
| Vent Stack | Upper portion of the soil stack above the topmost fixture through which gases and odors escape. |
| Venting Materials | Materials used for venting, i.e. PVC, CPVC, ABS, metal. |
| Venturi | A short tube with a tapered constriction in the middle that causes an increase in the velocity of flow of a fluid and a corresponding decrease in fluid pressure and that is used for creating a suction in a vacuum pump. |
| Viscosity | The resistance of fluids to flow, due to internal forces and friction between molecules, which increases as its temperature decreases. |
| Vitreous Surface | Material on some plumbing fixtures derived from or consisting of glass, translucent, and low on porosity. |
| Vitreous China | Ceramic materials fired at high temperature to form a non-porous body, having exposed surfaces coated with ceramic glaze fused to the body. This is used to form bathroom fixtures such as toilets, bidets, and lavs. |
| Volatile | Capable of vaporization at a relatively low temperature. |
| Volumetric | Refers to measurement by volume rather than weight. |
| Volute Casing | Derives is name from a spiral shaped casing surrounding the pump impeller. It converts velocity energy to pressure energy. |
| Voral Tube | Flexible steel hose used for hand-held shower sprays. |
| WC | Water Closet |
| WH | White finish on faucets. |
| Wall Thickness | The thickness of the tubing wall. |
| Wash-Down Water Closet | Water closet having a siphon trapway at the front of the bowl, and integral flushing rim. |
| Waste Arm Drain | An extension pipe, usually to extend a sink drain into a wall. |
| Waste & Overflow Drain | An assembly for a bathtub. The outlet at the top removes the overflow water during tub filling and the drain at the bottom removes wastewater when the tub is drained. |
| Waste Plug | Drain stopper on a bathtub drain |
| Waste Shoe | Bathtub drain assembly. |
| Waste Stack | See Soil Stack. The vertical main pipe in a drainage system, extending one or more stories. |
| Water Closet | A toilet. |
| 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 Horse Power (WHP) | The calculated horse power produced by the pump using the formula WHP = head x gpm/3960. |
| Water Service Pipe | The pipe from the water main or other sources of potable water supply to the water-distributing system of the building served. |
| Water Spot | Water surface in the toilet bowl once the flush is completed. |
| Water Table | Level below the earth’s surface at which the ground becomes saturated with water. |
| Waterway Fitting | A channel through which water can flow; connects water heater to inlet and outlet lines. |
| Wave Washer | A washer, common in drain linkages, which provides pressure against a ball or other mechanism even when the opposing nut is not fully tightened. |
| Weak Well | Weak well application occurs when the pump lowers the water level in the well faster than the well can replenish itself. |
| Weir | A long notch with a horizontal edge, as in the top of a vertical plate or plank, through which water flows, used in measuring the quantity of flowing water. |
| Well Casing | A steel or plastic pipe inserted into a drilled well to prevent dirt and debris from contaminating the water. |
| Wellpoint | A pipe fitted with a driving point and a fine mesh screen used to remove underground water. A complete set of equipment for drying up ground including wellpoints, connecting pipes and pumps. |
| Wet Vent | Drain or waste pipe that also acts for one or more fixtures on the same line. |
| Whirlpool Tub | A bathtub with circulation jets in various spots throughout the tub that provide therapeutic massaging action. |
| Widespread | A style of bathroom lavatory faucet having separate spout and handles, usually 8” from center of handle to handle. |
| Working Pressure | Maximum pressure of the operating system permissible. |
| Working Water | Water used in a home for most general purposes including bathing and laundering. |
| Wrought Copper Fittings | Plumbing fittings used to connect copper tubes made of mechanically worked and toughened copper as opposed to an as-cast brittle copper. |
| Wye | A Y-shaped fitting with three openings used to create branch lines. Allows one pipe to be joined to another at a 45 degree angle. |
| XH | Extra Heavy |
| XL | Extra Large |
| XLG | Extra Long |
| XS | Extra Small |
| Yellow Tipping | A flame condition caused by too severe a reduction in primary air. The yellow color is caused by glowing carbon particles in the flame. It can be corrected by the injection of more primary air. |
| Yoke | Usually a brass casting that holds both the hot and cold valves and the mixing chamber for the water. May also refer to an assembly of copper or other metal which serves the same function. |
| Yoke Vent | A pipe connecting upward from a soil or waste stack to a vent stack for the purpose of preventing pressure changes in the stacks. |
| Zeolite | A group of hydrated sodium aluminosilicates, either natural or synthetic, with ion exchange properties. |
| Zero Soft | Water with a total hardness less than 1.0 grain per U.S. gallon, as calcium carbonate. |
| 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. |
