How swimming pool pump works

Most swimming pool pumps are self-priming centrifugal pumps. These pumps must have a vacuum chamber, commonly known as a pump housing. The pump housing must be filled with water in order for any pump to create a vacuum, resulting in your pump pulling the water out of your swimming pool or spa. The pool pump housing will remain full of water while the pump is on, and will remain full or partially full of water when the pump is shut off.

When you turn on the pool pump the motor will begin to rotate on high speed (dual speed pumps rotate at the preselected speed). The motor drives the pump impeller, located inside the pumps center portion at the opposite end, away from the electrical switch portion of the motor. While the motor is rotating, the tips of the impeller are sealed hydraulically inside of the pump diffuser, this allows self-priming to occur.

Self-priming can only occurr when the pump has a diffuser. Some pool pumps have a separate diffuser, others have the diffuser molded into the pool pump’s cover, refer to your Owner’s Manual for your pump. The diffuser helps to eliminate any air coming into the pool pump housing, suction piping, or hoses on above ground pools. When all the air is being removed from the system, you will notice the bubbles returning to the pool through the return fittings. The impeller acts to convert water velocity into water pressure, which is registered on your filter pressure gauge. The actual Gallons Per Minute (GPM) varies with the type of pump and the horsepower. Check your Owner’s Manual for more information (owner’s manuals can be found online under the detailed page of your pump).

Self-priming pool pumps are very dependable and simple in design. They require a sufficient supply of water from the swimming pool or spa, and no air in the suction lines. Air could come from a loose strainer cover, a leak in any valve, a pin hole in any suction line or any crack or loose connections in the underground piping. Your swimming pool pump should be kept free of dirt and also located where it can be protected from flooding during heavy rain fall. If your pool pump motor becomes flooded you will probably have to replace it (pump motors damaged by flooding are not covered by warranty)

Below are some general problems you may come across with your pump…

	Why do i get lots of bubbles coming from my pool returns? This is a very common problem and quite easily solved. Most of the time this will be caused by your strainer basket inside your pool being full of debris. Just go through your normal regime of turning off the pump and clean out the basket.
	Why does my pump make alot of noise? This is mainly due to faulty or worn out bearings or in some cases a wronly positioned lever on the multi-port valve. Pump bearings can be fixed by a professional, the pump does not always have to be thrown away. Contact you local pool professional and he will be able to advise you.
	Why does my pump not draw water? There can be quite a few reasons for this problem. Firstly i would make sure the filter and pump basket are clean, also check for any pipe blockage in the suction side. One of the main causes of total loss of suction is a faulty impeller. If it gets to a stage were everything is clean and no blockages, then call in a trusted local professional. Like all things that have an electrical supply — SAFETY FIRST—

Related articles

How a swimming pool works
How we get water
Types of swimming pools
How swimming pool pump works

How a pool sand filter works