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Pool pump too powerful: the signs and the fixes

Updated : · Piscines VP

A pump too powerful for the pool, filter or plumbing is noisy, can cavitate, raises filter pressure and uses too much power. With a variable-speed pump, simply lower the speed. With a single-speed pump, replacing it with a variable-speed or properly sized pump is often the best fix.

An oversized pump is like driving in first gear on the highway: noisy, straining and thirsty.

The signs

The fixes

  1. Variable-speed pump: lower the speed to the flow you need. Free and immediate.
  2. Single-speed pump: consider a variable-speed pump or a properly sized one. See Choosing a pool pump.
  3. Don’t close a suction valve to “brake” the pump: risk of cavitation.

Estimate the difference

Our electricity cost calculator shows what the pump costs at full and reduced speed.

Frequently asked questions

Can I close a valve to reduce flow?

Closing a suction-side valve can make the pump cavitate and damage it. It's not a good way to compensate for an oversized pump.

How do I know if my pump is too powerful?

Compare its flow with the filter's maximum flow and the pool's need (volume ÷ 6 to 8 hours). A gravel sound, very strong returns and high filter pressure are clues.

Not sure of the cause? Take the 2-question diagnosis →

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