Choosing a pool pump: flow, power and noise
Updated : · Piscines VP
Choose a pump by the flow you need, not by horsepower. It should pass all the water through the filter in a reasonable time, without exceeding the filter's maximum flow or what the plumbing can handle. An oversized pump is louder, wears the filter and costs more. Variable speed lets you match the flow and cut noise.
“Get the biggest one, it’ll filter better.” It’s the most common mistake, and it costs a lot in noise and electricity.
Start from flow, not horsepower
- Pool volume: see our volume calculator.
- Target turnover time: a common target is passing all the water through the filter in 6 to 8 hours.
- Flow needed = volume ÷ time.
- Check the filter: the pump shouldn’t exceed its maximum flow.
- Check the plumbing: small pipes limit flow, whatever the pump.
Why too big is a problem
- More noise and vibration.
- Cavitation if the suction side can’t keep up. See Cavitation.
- The filter works poorly (water passes too fast).
- Higher electricity bill. See the cost calculator.
Variable speed: the right reflex
A variable-speed pump adjusts to the flow you need: low speed for filtration, high speed for vacuuming or backwashing. See Is a variable-speed pump worth it?.
Think about noise when buying
- Compare the sound levels manufacturers list (in dB), at the same distance.
- Plan where the pump will go and what it will sit on. See Building a good base.
Piscines VP advises on and installs pumps in Laval and the Basses-Laurentides, Quebec.
Frequently asked questions
Does a more powerful pump clean better?
No. Beyond the flow the pool needs, a bigger pump pushes water too fast through the filter, makes more noise and uses more power, without improving water quality.
How do I find my filter's maximum flow?
It's on the filter label or in its manual. The pump shouldn't exceed it.
Not sure of the cause? Take the 2-question diagnosis →
Be the first to know
The first batch will be limited. People on the list hear before anyone else. One email, no ads, no sharing.
Read next
Where and how to install your pool pump so it bothers less
Slab, pavers, wood deck or shed: where to put your pool pump to reduce noise for you and your neighbours. The common mistakes.
Building a good base for your pool pump
Concrete pad, pavers, blocks or a deck: how to prepare a solid, level, well-drained base for your pool pump and filter.
Reinstalling your pool pump in spring
Your pump spent the winter indoors? How to reinstall it in spring without leaks or noise: fittings, seals, level, priming and first start.