Do Pool Pumps Have to Run All the Time?

By: Sarah Gleim  | 
man chilling in pool
Nothing beats relaxing in a cool pool on a hot day. But how long do you have to run the pump to make sure the water is always sparkling clean? Flashpop/Getty Images

Key Takeaways

  • Pool pumps do not need to run all the time; running them for about eight total hours a day, especially during summer, is usually sufficient for proper circulation and filtration.
  • Operating your pump during off-peak electricity hours, mostly at night, can help reduce maintenance costs without compromising water quality.
  • Utilizing a pump timer allows for the flexibility of breaking up the pump's running time into several shorter periods throughout the day, ensuring the pool stays clean and chemicals are distributed evenly.

Much of the world is experiencing oppressively hot temperatures this summer. And there's probably no better way to cool off than taking a dip in a cool pool.

Of course, that's only if your pool is properly maintained and that includes running the pump to filter the water. But does the pump have to run all the time, as in 24 hours a day? Before you just turn it on and leave it, let's first talk about what a pool pump actually does.


The pump is the main part of the swimming pool circulation system. When it's running, it keeps the water moving; otherwise the water would become stagnant and things like algae and bacteria could grow. The pump also clears debris from the water and keeps those pool chemicals mixed by pushing water through the filtration system.

Many variables determine how much time you need to run the filtration system, including the size of the pool and how you use it. But the bottom line is 100 percent of your pool's water must filter through the system at least once a day — something called turnover rate.


Your Pool's Turnover Rate

You can calculate your pool's turnover rate pretty easily. You just need to know a few numbers, including the volume of your pool. If you don't know how to determine it, has a handy calculator to help you figure it out. Once you know your pool's volume, divide that number by eight to get gallons per hour (GPH). Most pool pumps are gallons per minute, so divide the GPH by 60 to get how many gallons per minute (GPM). This is the how many minutes your pump has to filter to get full turnover. For most pools, it's going to be about eight hours.

Total Pool Volume ÷ 8 = GPH GPH ÷ 60 = GPM


When to Run Your Pool Pump

Now that you know about how many hours it should take your pool to filter the water run through the system in 24 hours, there are other things to consider, like what time of the day is best to run the pump. Do you have to run it for eight consecutive hours, or can you split the hours up?

First, consider running your pump during off-peak electricity hours. This may mean you run it mostly at night, especially if you live in a hot climate where people are using air conditioners during the peak of the day. Doing this may help lower your pool maintenance costs.


But there are times when you have to run the pump during off-peak hours, like when you add chemicals to your pool. The water must be circulating so the chemicals get distributed throughout the water. You can — and should — add pool shock at night, though. The sun can burn shock off during the hot daytime hours, but you still need to have the pump running to circulate the water.

Finally, another way to keep the costs down of running your pool pump is to break up the times you turn it on. You can run it several times a day for short periods of time — as long as it runs for about eight total hours in 24 hours, especially in the summer. The easiest way to do this is with a pump timer. However, if your pool is constantly being used, you may need to keep the pump on for up to eight consecutive hours every day, and check the water clarity and chemical balance.


Frequently Asked Questions

Is it more efficient to run the pool pump continuously or in intervals?
Running the pool pump in intervals can be more energy-efficient and still keep the pool clean, as long as it runs the recommended total hours daily.
How does the use of a pool cover affect the running time of a pool pump?
A pool cover can reduce debris and evaporation, potentially allowing for reduced pump running times by keeping the pool cleaner and minimizing water and chemical loss.