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How Often to Run a Pool Pump

The pump and filter system of a swimming pool is a crucial factor in the general appearance of the water. If a system is too small to provide adequate filtration, the resulting inefficiency can produce cloudy or dinghy looking water. A correctlysized pump, however, moves the water through the system and sends it back to the pool, filtered, cleaned and ready for swimming.


A pool pump should run a minimum of 12 hours a day to turnover, or filter, all the water in a pool. A number of factors can reduce the amount of time required to filter the pool, one of which is the gallon size of your pool. How big your pool is determines how quickly your pump can complete a full turnover of all the water. Other factors are the size of the hoses, or PVC piping, that go to and from the pool, the pump horsepower, bather load and the degree of maintenance the pool receives. The most popular size pool in the country has long been a 24-foot round above ground pool. In a normal situation, as an example, where the pump is a 1-horsepower, the bather load is average and maintenance is performed on a weekly basis, the pool has 13,550 gallons and uses 1 ½-inch hoses to and from the pool. The 1-horsepower pump can turn over 75 gallons per minute, which equals 4,500 gallons per hour. Divide 4,500 gallons per hour into 13,550 gallons of pool water, and the answer equals complete turnover in 3.01 hours. Therefore, in this typical scenario, in a little over 3 hours, the pump and filter system have completely filtered the entire pool.


Some people prefer to run their pumps in the daytime because people use the pool during the day, and if a hose disconnects, or the pressure gauge reads too high, someone can step in and resolve the problem. Other pool owners prefer not to hear the noise of the filter system running while they are trying to relax in the pool, so they run it after swimming hours are over. However, the system may be near the homeowner’s bedroom windows, and the last thing they want is a noisy pump disturbing sleep all night. The reasons for daytime or nighttime preferences depend on the individual homeowner and the location of the pool, but the main thing is that the pool does get filtered, regardless of when--during the day or night.


Some pool owners turn their pumps and filter systems on in the late spring and run it constantly throughout the entire summer. They shut it off after Labor Day or whenever the cold weather arrives in their part of the country. These systems, designed to run continuously, rain or shine, can certainly accommodate these full-time users.

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