Common Swimming Pool Terms, Explanations, Problems, & Solutions

Air Relief Valve (aka Air Bleeder): used on top of the filter, this device is used to let the air escape and allow the tank to fill with water. It’s critical to open the air bleeder before restarting the motor. The force of the water can compress the air and cause excessive pressure which can damage the equipment.

    Common Problems & Solutions:
  • Problem: The air valve won’t open.
    Solution: The unit needs to be disassembled with tools and lubricated.
  • Problem: Water keeps squirting out even when closed.
    Solution: The rubber seal ring on the inside of the unit is damaged or missing and needs replacement.
  • Problem: The valve is opening and nothing comes out.
    Solution: The passage is clogged with debris and needs to be disassembled and unclogged.

Backwash: the process of running water through a filter in the reverse direction to flush the filter of debris and contaminents, freeing up the filter to be less restricted so the water can pass through the filter more efficiently, collecting more debris.

    Common Problems & Solutions:
  • Problem: The water flow (flowrate) didn’t increase after the backwash, and the tanks pressure is still higher than usual.
    Solution: More backwashing is needed. Be sure that the hair and lint strainer is always cleaned before backwashing.
  • Problem: No water is coming out of the pipe.
    Solution: The pump must be primed.

Cartridge: the element in a filter, covered with pleats of fabric, to strain debris and contaminants from the water passing through it.

    Common Problems & Solutions:
  • Problem: The filter becomes clogged and requires cleaning.
    Solution: Remove the filter element, replace with the previously cleaned set, and rinse dirty elements with pressure or soak in a degreaser (TSP).
  • Problem: The filter fabric rips, and allows dirty water to pass through.
    Solution: The damaged filter needs replacement.

Caulking: material used in a joint to create a waterproof seal.

    Common Problems & Solutions:
  • Problem: Splitting from the sides of the joint, holes where it was applied too thin. This allow water to seep into the joint.
    Solution: Remove old caulk, clean joint, tape both sides of joint, apply caulk compound, strike to smooth finish and pull tape. Correct any imperfections by hand with a release agent and allow to dry.

Centrifugal Force: the outward force created by an object in circular motion. The force that is created by water pumps to move water.

Chlorinator: a mechanical device or pump that delivers chlorine to a body of water.

    Common Problems & Solutions:
  • Problem: The pump tube wears out.
    Solution: Replace the pump tube assembly.
  • Problem: The strainer is clogged.
    Solution: Replace or clean the strainer.
  • Problem: The injection fitting is clogged.
    Solution: Replace or clean the injector.
  • Problem: The tubing is cracked or split, allowing air to disrupt suction force or the chlorine to leak.
    Solution: Search for the leak, possibly shorten the tubing to eliminate the leak which is common at the ends or replace all tubing.

Circulation System: the combination of pipes, pump, filter, and other components through which water flows.

    Common Problems & Solutions:
  • Problem: The filter is clogged.
    Solution: Backwash or change cartridges.
  • Problem: The strainer is clogged.
    Solution: Clean the strainer (a must before each backwash).
  • Problem: Loss of prime.
    Solution: Familiarize yourself with each systems needs. Depending on system design and equipment, there will be different procedures. Refer to your pool chart.

Coping: the cap stone on the edge of a pool or spa mounted on the bond beam.

    Common Problems & Solutions:
  • Problem: Cracks
    Answer: A crack can be repaired with mortar or epoxy. This is a temporary repair to ensure a smooth, safe surface. If in very poor condition, replacement is required.
  • Problem: Hollow or delaminating at bonding surface.
    Solution: Re-set the stone by removing stone cleaning surfaces and reapplying in a fresh mortar bed. You can also replace the stone.

Discharge: the flow of water out of a pipe or port.

    Common Problems & Solutions:
  • Problem: Water leaks.
    Solution: The PVC piping and fittings must be removed and replaced to reseal the threaded discharge, this commonly is a repair that is conducted by an experienced repair technician. If the discharge has a bolted flange, a rubber gasket makes the seal, and it may just need tightening.

Effluent: the water discharging from a pipe or equipment.

Erosion System: a type of chemical feeder in which tablet sanitizer is slowly dissolved by constant flow of water through the device.

    Common Problems & Solutions:
  • Problem: Chemical fumes.
    Solution: Wear safety gear when checking the system. Try to add chemicals to an empty feeder only. Never add the residual "dust" from the container.
  • Problem: Slow addition of chemical.
    Answer: A supplemental chemical, such as granular chlorine, may be needed for superchlorination.

Filter Run: the time between cleanings, expressed as the total running time of the system, also called the filter cycle.

    Common Problems & Solutions:
  • Problem: Inconsistent or irregular cleaning can result in turbid water. Awareness of the filter run will allow the prediction of cleaning frequency.
    Solution: Consistent record keeping, including change in flowrates, tank pressure, and pressure differential will reveal the patterns of the filter run.

Flow Meter: a device for measuring the rate of water passing through a given pipe, expressed in gallons per minute (gpm).

    Common Problems & Solutions:
  • Problem: The float becomes stuck, indicating an inaccurate reading.
    Solution: Lightly tap the top of the flowmeter to vibrate the float and dislodge it. Be careful not to exert too much force on the unit, as it’s plastic and will break.
  • Problem: The painted numerals on the flowmeter become faded.
    Solution: Replace all flowmeters which have faded numerals to avoid rule violation.

Flow Rate: the volume of water passing a given point in a given time, expressed in gallons per minute (gpm).

    Common Problems & Solutions:
  • Problem: Flow rate is lower than the requirement.
    Solution: A low flow rate will be unacceptable to county inspectors, and indicative of a pump or filter restriction, or an improperly sized pump. High flow rates are acceptable as long as the rate does not exceed the filter system’s capacity.

Gate Valve: a valve that restricts water flow by raising and lowering a disc across the diameter of the pipe by means of a worm drive.

    Common Problems & Solutions:
  • Problem: Stripped threads at the worm drive, the round handle will keep spinning without moving the disc. The problem is not visible.
    Solution: Damaged valves need repair or replacement.

Gauge: refers to a measuring device, as in pressure gauge. Typically 0-60 p.s.i. Used to measure tank pressure, influent pressure, and effluent pressure on filtration systems.

    Common Problems & Solutions:
  • Problem: Some gauges are made with metal components which do not last in pump rooms due to the chemical fumes accelerating the deterioration.
    Solution: Replace any gauge that does not “zero out” when the system is off. Replace when needles are damaged or the unit fills with water.

Gunite: a dry mixture of sand and cement that is mixed with water at the nozzle and sprayed onto contoured and supported surfaces to build a pool or spa, creating the shell of the pool.

    Common Problems & Solutions:
  • Problem: In situations where the shell has not properly been waterproofed, damage to the top of the pool shell (bond beam) can occur with freezing temperatures.
    Solution: When the coping is removed, damage can become evident and must be repaired by removing all the deterioration and rebuilding.

High-rate Sand Filter: a filter using sand for the filtration media designed for high flow rates. Strains impurities larger than 50 to 80 microns. Uses pool water to clean dirty filters.

    Common Problems & Solutions:
  • Problem: Channeling
    Solution: May need to change filter sand due to the channeling of water around the sand rather than through it.
  • Problem: If internal components fail, sand will be forced into the pool.
    Solution: Internal components can be replaced but when this occurs, it is indicative of future labor intensive maintenance needs. At this point, it’s recommended you replace the entire unit.
  • Problem: Sand erosion
    Solution: Years of water passing over each grain makes them round instead of faceted and rough. Smooth sand does not catch and trap dirt as effectively.

Hose Bibb (also bib): the faucet to which a garden hose is attached.

    Common Problems & Solutions:
  • Problem: Requires a backflow preventer, will fail inspection from county if missing at pools.
    Solution: Be sure all hose bibs have back flow preventers, which are in place and operating properly to protect the potable water supply.

Hydrostatic Valve: a check valve located in the main drain of a pool to relieve hydrostatic pressure created by the groundwater. The valve allows groundwater into the pool, but does not let water out.

    Common Problems & Solutions:
  • Problem: If the spring loaded top is stuck open, the pool will leak at this location when full.
    Solution: Before a pool is full, it’s important to check proper operation. Once a pool is filled and diagnosed as leaking, this could be a common source. Check by lifting and dropping the top to insure a seal.

Impeller: rotating part of a pump that creates centrifugal force to create pressure and suction. The impeller is said to be closed, if it is shrouded (covered) on both sides of the vanes, or semi-open if shrouded on one side, while the interior surface of the volute creates a partial shroud on the other side.

    Common Problems & Solutions:
  • Problem: If an impeller gets clogged, obstructed, or if it gets damaged in any way, the flow rate will be reduced, causing filtration problems.
    Solution: Protect the impeller with a clean strainer basket, which is intact, has no holes, and isn’t damaged. Be sure the basket is always in place, especially at pool start up.

Laterals: the slotted horizontal collection tubes at the bottom of a sand filter, installed on the drain manifold hub.

    Common Problems & Solutions:
  • Problem: Broken laterals will allow filter sand to pass through the filter and into the pool.
    Solution: It’s difficult and labor intensive to repair the laterals. This type of internal break in a tank is indicative of the wear of the tank, we recommend tank replacement.

Leafmaster: a brand name; leafmaster is a term applied to a device that vacuums large debris from a pool by means of water pressure created with a garden hose.

    Common Problems & Solutions:
  • Problem: Leafmasters will not work in shallow water. The wheels commonly break, and the bag, if not properly secured, will blow off of the body.
    Solution: Be sure to check equipment before trying to use. Make sure the bag is secured. The greater the water pressure, the better the performance of the unit.

Leaf Rake: a large open net secured to a frame that attaches to a telepole that is used to skim debris from the surface of the water. Different from a leaf net, the screen is like a bag which will hold a greater capacity of debris.

    Common Problems & Solutions:
  • Problem: The net material ripped.
    Solution: Keep it clean, as excessive weight can cause the material to rip and debris to pass through.

Main Drain: the suction fitting located in the lowest portion of a body of water; secondary intake for the circulation system.

    Common Problems & Solutions:
  • Problem: Single drains or non VGB approved covers can be an entrapment hazard.
    Solution: Dual drain conversion with VGB approved frames and grates are the best solution. Never operate the drain without the skimmer valve open.

Manifold: an assembly that combines several other components together; a pipe fitting with several lateral outlets for connecting other lines.

    Common Problems & Solutions:
  • Problem: Filter manifolds or suction manifolds may develop leaks or valves need replacement.
    Solution: Suction leaks will allow air in; pressure leaks will allow water out. Correct by diagnosing leak source and repair/replace equipment fittings, or pipe as needed.

Niche: the housing built into the wall of a pool for an underwater light.

    Common Problems & Solutions:
  • Problem: The conduit (plastic tube) which protects the cord for the light in the back of the niche is a common source for water leaks.
    Solution: When the pool is empty, a conduit sealer can be inserted into the back of the niche at the gap around the cord inside of the conduit (also called butyl tape).

National Pipe Thread (NPT): the generally accepted standard specifications for threaded plumbing pipe and fittings. NPT threading is slightly tapered, so when the treaded fitting is tightened a seal occurs.

    Common Problems & Solutions:
  • Problem: The joint compound dries out, causing leaks. Heat will distort the threads and break the seal in PVC.
    Solution: When the thread becomes distorted, the fitting, plug, or device will need repair/replacement.

Plaster: a hand-applied combination of white cement, aggregates, and additives that covers the shell of a gunite pool or spa to waterproof and add beauty. Plaster can also be colored.

    Common Problems & Solutions:
  • Problem: Separation or failure of the bond in layered materials, such as plaster to gunite, also referred to as “plaster pops.”
    Solution: Replastering needs to occur when the surface is cracked, chipped, or has popped, or if the surface becomes too rough. Underwater patching of plaster can occur with epoxy (pool putty).

Pressure Gauge: a device that registers the pressure in a water or air system, expressed in pounds per square inch (psi).

    Common Problems & Solutions:
  • Problem: Gauges are sensitive, and are subject to deterioration while in an environment like a pool pump room with chemical fumes.
    Solution: Replace at once, if there are problems with inaccurate readings, sticking needles, or if it does not “zero out.”

Prime: the process of initiating water flow in a pump to begin circulation by displacing air in the suction side of the circulation system.

    Common Problems & Solutions:
  • Problem: Air is displaced usually by filling with water and resealing the strainer. Be sure the valves are closed to prevent water from running back into the pool. Before starting, be sure to check that there is enough water in the pool and that no skimmer weirs are stuck in the upright position, restricting water flow to the skimmer line.
    Solution: The physics involved in displacing the air may require some trial-and-error testing. Listen to the sound the pump makes when working properly. Listen for spraying noises or a gurgling sound to determine your completion. Turn off the pump. Close the valves at suction manifold. Open and clean the strainer, and then fill with water. Properly seal the strainer lid. Be sure it’s sealed properly to eliminate air entering at lid. Ensure all valves are in proper filter positions. Open the air reliefs on the top of the filter tanks to allow water to displace air as the tanks fill (unopened air valves will allow air to compress at dangerously high levels). Turn on the pump, and slowly open suction valves to allow pool water to enter the strainer and pump.

PSI: Pounds per square inch.

PVC: Polyvinyl Chloride. The type of plastic pipe and fittings most commonly used in pool and spa plumbing.

    Common Problems & Solutions:
  • Problem: Connections are made by gluing the pipe together with connectors. Where a glue joint (slip joint) is mostly trouble free, threaded connections are more common leak points than solvent welding.
    Solution: Each time a treaded connection is utilized, a thread sealant must be applied to the threads before screwing together. If threads have been distorted by heat (pump running dry), the piping section must be rebuilt with new fittings.

Return: the line and/or fitting through which filtered water is discharged into a body of water, also called an inlet. Return fittings are designed with adjustable plates, which allow the flow of water through the unit to be regulated. The returns closest to the pump get more flow; the ones furthest away get less.

    Common Problems & Solutions:
  • Problem: Plastic covers can break and screw hole threads strip out.
    Solution: Repairs to returns are easiest when the pool is empty. Always check for problems before filling. Repairs are difficult when required under water. A temporary repair is to secure the cover with underwater epoxy resin or put in an oversized stainless steel screw.

Sight Glass: a clear glass or plastic section of pipe that allows viewing of the water in the line. Used when backwashing filters, a way to know when the discharge water is clean by water clarity.

    Common Problems & Solutions:
  • Problem: Can be a source of a water leak.
    Solution: Be sure all parts are properly installed and rubber seals are properly lubricated.

Skimmer: a part of the circulation system that removes debris from the surface of the water by drawing surface water through it.

    Common Problems & Solutions:
  • Problem: If the water level is not high enough in the pool to keep the water flowing into the skimmer, it will suck air into the pump and cause the pump to lose prime. The weir can get stuck on the side walls if not aligned, and will restrict water from flowing into the skimmer, also causing the same effect.
    Solution: Keep the water level at proper levels, keep the baskets clean, and make sure the weir is in place and not rubbing the skimmer wall. Also check for cracks, as this plastic device is susceptible to damage, causing water leaks.

Strainer Basket: a plastic or stainless steel mesh container that strains debris from water flowing through it inside the strainer pot.

    Common Problems & Solutions:
  • Problem: If missing or if there are holes, debris will pass through and will clog the pump impeller. If not regularly cleaned, the flow will be restricted.
    Solution: Check the basket regularly to insure proper placement, lack of holes and to clean out debris.

Strainer Pot: the housing on the intake side of a pump that contains a strainer basket and serves as a water reservoir to assist in priming (also called hair and lint strainer).

    Common Problems & Solutions:
  • Problem: If the lid is metal, it can rust and will obstruct an airtight seal. Plastic lids, commonly found on smaller pumps, are mostly maintenance free.
    Solution: Overhauls which involve removing rust and lubricating the rubber seal will prevent air leaks (sucking air). Keep the plastic lids properly lubricated and clean.

Teflon Tape: a thin fabric provided on a roll used to coat threaded plumbing fittings to prevent leaks.

    Common Problems & Solutions:
  • Problem: If not wound onto the threads in the proper direction, the tape can unravel as the threads are turned.
    Solution: Always wrap the threads going counterclockwise. On pump discharges, use a combination of Teflon tape and silicone sealant for the best seal.

Telepole: a metal or fiberglass pole that commonly extends to twice its original length with the two sections locking together. The telepole is used with most pool and spa cleaning tools.

    Common Problems & Solutions:
  • Problem: The metal pole end can become bent, restricting the removal and installation of the cleaning tools. The locking mechanisms can be problematic.
    Solution: Always treat with care, and hang poles rather than stand on end. Keep the locking mechanism lubricated and do not over extend pole and push too hard, as this may result in the pole bending. Do not use near overhead power lines.

Turbidity: cloudiness.

    Common Problems & Solutions:
  • Problem: Turbidity restricts the ability to see “through” the water.
    Solution: Keep the filtration system clean at proper flow rates and keep chemicals at proper levels.

Turnover Rate: The amount of time required for a circulation system to filter 100 percent of the pool water.

    Common Problems & Solutions:
  • Problem: When renovating a pool, the pump may be required to be upgraded for a quicker turnover rate.
    Solution: Once the pump is sized and installed, the turnover rate cannot be altered or changed, it can only be maintained by checking and maintaining your flowrate.

Valve: a device in plumbing that controls the flow of water. Three common styles of valves are wafer, ball, and gate. Wafer and ball style are similar. A wafer valve involves a circular disc, and a ball valve has a sphere with a hole through the center. Both styles are connected to an arm style handle, which goes from open to closed position with ¼ swing of the handle. When the handle is perpendicular to the valve and piping, it is closed. When parallel, it’s open. A gate style valve involves a sliding plate which is threaded. As you spin the wheel style handle, the threaded rod connected to the sliding plate closes the valve as you spin clockwise and opens the valve as you spin counterclockwise.

    Common Problems & Solutions:
  • Problem: The primary problem with the valves or valving systems (called manifolds) is not the failure of the valve, but more understanding the valve positions and how they are set at your pool for the desired mode. Air leaking at valves on the suction side of the pump can be common. Water leaks on the pressure side are also ordinary.
    Solution: Valves with threaded connections can be reused during a plumbing repair if the valve opens and closes properly and doesn’t leak. However, the correction of most valve problems involves removal and replacement of the valve and surrounding plumbing.

Weir: the barrier in a skimmer over which water flows. A floating weir raises and lowers its level to match the water level in a pool or spa. Another type is shaped like a barrel and floats up and down inside the skimmer basket. The design is such that the top ¼” to ½” of water constantly flows into the skimmer basket. This flow pattern of water collects the floating debris in a pool. Proper skimmer function will reduce the need for vacuuming.

    Common Problems & Solutions:
  • Problem: The weir can get stuck on the sidewalls of the skimmer if not aligned, and will restrict water from flowing into the skimmer, also causing loss of flow, due to the pump sucking air. Weirs, as with many pool parts, have to be made of plastic, which is impervious to corrosion from pool chemicals. The plastic becomes brittle over time, and the weirs commonly break or crack.
    Solution: A weir can be trimmed to free an obstructed pattern of movement. However, due to the fact that they are relatively inexpensive and the replacement is easily completed, this is a common replacement part through the summer. Frequently check all weirs for proper placement and unobstructed movement.


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