Pool Equipment Terms

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Pool Equipment Terminology & Definitions:

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

AIR BLEEDER ASSEMBLY: Located on the top of the filter, sometimes accompanied by a pressure gauge, the bleeder is opened to release air trapped in the filter. >Top<

AUTOMATIC POOL CLEANER: A device which agitates or vacuum debris from the walls and floor of the pool.

BACKFILL: The repositioning of the soil after construction of a pool.

BACKWASH: The process of thoroughly cleaning the filter medium and/or elements by reversing the flow of water through the filter to waste.

BALL VALVE: A device with a hollowed out ball inside which can be turned with an external handle to decrease or increase flow.

BLOWER: Plumbed into the spa return line, air is injected to produce fun bubbles and a hydrotherapy effect in the spa.

BOOSTER PUMP: Secondary to the filter pump, a booster pump is used to power an automatic pool cleaner such as Polaris or Letro.
terminology
BTU: British Thermal Unit. A unit of measurement for the use of gas by a gas appliance. Pool heaters are rated by their consumption.

CAPACITY: The gallonage of the pool. Want the formula?

CARTRIDGE: One type of filtration, the cartridge is a pleated, porous element through which water is passed through.

CHECK VALVE: A one way flow device.

CHLORINATOR: Devices which allow for the safe, controlled introduction of chlorine into the water.

CHLORINE GENERATOR: A miniature chlorine factory, this device creates its own sanitizer for your pool.

CIRCUIT BREAKER: A switch which allows manual override of an electrical circuit. It also automatically breaks the circuit when current fluctuations are detected.

CIRCULATION SYSTEM: The "circuit" of plumbing which continuously carries the water out of the pool, through the pump & filter, and returns it to the pool.

CONDUIT: A pipe, usually gray pvc or flexible pvc designed to carry wires from a source (i.e. time clock) to a load (i.e. pump motor).

COPING: The capstone on top of the bond beam which finishes the edge around a pool or spa. It may be precast concrete or brick. On vinyl liner pools pre fab coping is usually part of an integrated system for the wall, vinyl liner and deck.

COUPLING: A plumbing fitting designed to join two pieces of pipe.

COVERS:

Automatic covers: Solid, reinforced vinyl which rolls onto a reel on one end of the pool and attaches on the sides into small aluminum tracks. Can be motorized or hand crank. Some models may snap the sides into small anchors placed into the deck, providing more shape flexibility. Provides safety (with water pumped off), debris protection and heat/chemical/water retention.

Hard Covers: A cover which rests on the edge or coping of the spa or small pool. Provides a barrier to debris and possibly people, while keeping the heat trapped in.

Solar Covers: Sometimes called a thermal blanket, this cover floats on the surface, magnifying the sun's rays to warm the water and also provide chemical/heat/water evaporation.

Winter Covers: A barrier to sun and debris, winter covers secure the pool from contamination. These are subdivided below.

Mesh Covers: These stretch tightly across the pool like a trampoline. The only covers which can be called safety covers in that the mesh polypropylene allows precipitation to pass through.

Solid Covers: These are usually made of some form of plastic or vinyl and are secured around the edges either by aqua bloks or similar weight or the edges attach to anchors set in the concrete or wood deck.

DIATOMACEOUS EARTH: The filtering medium of the DE filter, this dry powder is the fossilized remains of the ancient plankton, diatom.

DIATOMACEOUS EARTH FILTER: A filter tank containing fabric covered grids which hold the DE powder up against the flow of the water.

DIVERTER VALVE: Used in a twin port skimmer, a diverter allows the operator to manipulate the amount of flow from the main drain and skimmer to the pump.

DRAIN: Also called the main drain, this plumbing fitting is the start of one suction line to the pump and is usually situated at or near the center bottom of the pool.

EFFLUENT: The water that flows out of the pump, on its way through the filter, heating and treating equipment, and returning to the pool. Also known as the pressure side.

ELBOW: A 90 or 45 degree plumbing fitting. Used where your pipes take a turn.

FILTER: A device used to remove particles suspended in the water by pumping water through a porous substance or material.

FILTER ELEMENT: A device inside a filter tank designed to entrap solids and direct water through a manifold system to exit the filter.

Cartridge filter elements and DE filter grids are two examples.

FILTER MEDIUM: A finely graded material, such as sand, diatomaceous earth, polyester fabric or anthracite coal that removes suspended particles from water passing through it.

FILTER PUMP: The device that pulls water from the pool and pushes it through the filter on its way back to the pool.

FILTRATION RATE: The rate of water pumped through a filter, in gallons per minute (gpm).

GATE VALVE: The type that spins "lefty-loosey; righty-tighty".

GAS VALVE: An electronic valve in the pool heater that directs gas flow from the meter to the pilot and the burner tray.

GROUND-FAULT CIRCUIT-INTERRUPTER: A GFCI device protects a circuit from branching off by de-energizing the path of electricity very quickly when it senses current loss. An important safety device around water (the pool?).

GUNITE: A dry mixture of cement and sand mixed with water at the "gun"; hence the name. A gunite operator "shoots" the pool's rough shape, while finishers trowel after.

HEATER: A device used to heat the water. It may be electric, fuel operated or solar powered heat.

HEAT EXCHANGER: A set of 8 or 10 ribbed copper tubes that absorb the heat produced below it and transfer it to the water cycling through its tubes.

HEAT PUMP: The antithesis of the air conditioner, the heat pump's cooling coil removes heat from the air while the condenser coil transfers it to water cycling through it.

HOT TUB: Usually considered a circular, wooden vessel filled with heated and circulated water.

HYDROSTATIC PRESSURE: A force involving built up ground water which creates upward pressure beneath the pool shell.

HYDROSTATIC RELIEF VALVE: Fitting(s) installed in the floor of the pool designed to manually or automatically release hydrostatic pressure beneath the pool by allowing ground water into the pool.

IMPELLER: The rotating vanes of a centrifugal pump; its action creates the flow of water. The impeller is shaft driven by an electric motor.

INFLUENT: The water coming into and up to the impeller from the suction lines. These pipes are under vacumn pressure.

JANDY VALVE: A brand name of a three way valve, which has simplified pool plumbing.

JET PUMP: Used in spas to provide additional thrust into the hydrotherapy jets.

LADDER BUMPERS: Rubber caps or inserts which protect the pool plaster or vinyl liner from the sharp steel ends of the ladder.

LATERALS: Elongated, capped plastic nipples at the bottom of a sand filter which are slotted to allow for water passage while keeping the sand in the filter tank.

LOAD: An electric device which consumes energy, placing a load on the source.

LOW WATER SUCTION: An influent fitting, typically low on the wall in the deep end of a vinyl liner pool. A cheaper alternative to a main drain.

MECHANICAL SEAL: A seal behind the impeller which prevents water from running out along the shaft of a motor. aka; pump seal.

MOTOR: A machine for converting electrical energy into mechanical energy. Your motor is known as the dry end of the filter pump. It drives the impeller, which moves the water.

MULTIPORT VALVE: A 4 or 6 position valve combining the functionality of several valves into one unit, revolutionizing pool plumbing. The six common functions are described below:

Filter: This is normal water flow through the filter, say, top to bottom. This is where the valve sits 99% of the time.

Backwash: When the pressure gauge indicates, you will need to backwash the filter. When the handle is turned to backwash, the flow through the filter is reversed, say, bottom to top. The effluent water (out of the filter) is directed to the waste line.

Rinse: After backwashing, it's a good idea to rinse for 15-20 seconds to remove any residual dirt that may "poof!" back into your pool after backwashing. Rinse flows through the water in filter fashion, say, top to bottom, but effluent is sent out the waste line.

Recirculate: This setting bypasses the filter, water coming into the multiport does a U-turn and heads back towards the pool. Used only when the filter is broken (at least it's circulating), or when adding specialty chemicals which specify using this setting.

Drain / Vacumn to waste: This useful setting allows you to vacumn up large volumes of debris that would either clog the filter or pass through it because of its small size. Dirt that is vacumned passes right out the waste line. It is also the setting of choice when draining the pool or lowering the water level (if you didn't need to backwash, which also lowers the water level).

PLASTER: A common type of interior finish applied over the concrete shell of an inground swimming pool.

PRESSURE CHECK: A test for the rate of water flow; also a test for leaks in plumbing by placing a line in question under pressure and waiting for the pressure to drop.

PRESSURE GAUGE: A device indicating pressure in a filter system. Provides a determination of how the system is operating, and informs us when service is required.

PRESSURE SIDE: The return side of the plumbing. The section from the pump impeller towards the pool.

PRESSURE SWITCH: A switch used in pool heaters which opens when the flow rate is insufficient for safe heater operation. This disrupts the circuit in the heater, preventing it from firing.

PLUNGER: The sliding disc assembly that changes valve position in a push-pull valve. For example; up for backwash, down for filtration.

PUSH-PULL VALVE: A two position valve used for backwashing sand or DE filters.

PUMP: A mechanical wet-end, powered by an electric motor, which causes hydraulic flow and pressure for the circulation of the pool water.

PVC: Polyvinyl chloride, which is used to make flexible and rigid PVC pipe used for pool plumbing.

RATE OF FLOW: Quantity of water flowing past a designated point within a specified time period, measured in gallons per minute (gpm).

RESTRICTED FLOW: The term used to describe a condition preventing full flow of water. Restriction can occur with full skimmer or strainer baskets, obstructions in the plumbing, dirty filter, undersized plumbing or equipment , or placing devices like, heaters, cleaners or fountains in the circulation system. Restriction on the suction side creates higher vacumn, (or suction) while on the pressure side creates higher pressure.

RE-BAR: Reinforcement bar, used to add strength to a concrete. After excavation of an in ground pool, a steel cage is formed out of re-bar, and the gunite shell is shot over and surrounding it.

SAND FILTER: A filter tank, usually fiberglass or ABS plastic, filled with sand and gravel. The pump diffuses water over the top of the sand bed, and forces it through the sand and into the laterals on the bottom.

SHOTCRETE: A different type of application of the concrete and sand mix which is used to "shoot the shell". Gunite is pumped dry and mixed with water at the gun, whereas shotcrete is pumped wet.

SKIMMER: A surface skimmer is a plumbing fitting set at water level, containing a weir mechanism and a debris basket. The skimmer is part of the suction side circulation system.

SKIMMER BASKET: Beneath the lid, the basket strains debris, as the first line of defense in filtering the water.

SKIMMER NET: Attached to a telescopic pole, a leaf rake is a very useful tool in keeping the pool clean. Also called a skimmer net are the flat, "dip and flip" nets, which aren't so useful.

STRAINER BASKET: The second line of defense is a basket at the pump. The holes in this are smaller than those in a skimmer basket, and prevent the pump impeller from clogging up.

SOLAR SYSTEM: Black mats of miniature plastic tubes through which water is pumped, absorbing the heat as it passes through. These mats are roof mounted with up & down plumbing connecting it.

SOURCE: Refers to the origination of electrical power. The source for your filter pump (load) is probably a timer clock.

SUCTION SIDE: The plumbing prior to and carrying water to the pump. This side is under vacumn pressure.

SPA: A filtered, hot water vessel with hydrotherapy jets and air induction. Can be portable or installed permanently. Jacuzzi is a brand name.

TEE: A plumbing fitting used to bring two pipes together into one, or vice-versa.

TEST KIT: What you should be using more frequently to determine the water balance in your pool.

TIME CLOCK: A mechanical device that controls the timed operation of your electrical equipment, primarily your filter and booster pumps.

TURNOVER: The amount of time it takes your pump to move all the water in your pool through the filter and back again. Usually, pools are designed for an eight hour turnover.

UNDERDRAIN: The lower collection system in a filter which directs filtered water back towards the pool. It also distributes water in reverse during backwashing. See laterals.

VACUUM: Refers to the low pressure condition created in the suction line. Also refers to the cleaning process of sucking leaves, algae and debris from the pool floor.

VALVES: A device placed in the plumbing line which restricts or obstructs water flow to create desired hydraulics, or may permit flow in one direction only (as in a check valve).

VENTURI: Increasing water velocity by restricting pipe size.

VINYL LINER: One type of interior finish. The liner is draped over a sand or cementitious floor, and locked into the top of the wall.

WEIR: The device in a skimmer that controls the amount of water coming into the skimmer, and keeps debris inside. That "flapper-gate thing".

For more great resources on pool supplies and parts, visit our friends at the PoolCenter.com