How Long Should I Run My Pool Pump?

Updated Jun 1, 2021

One of the most common questions we get from customers is the infamous, “How long should I run my pool pump?” It’s obviously one of the most important element to successful pool maintenance.

We have tested thousands of pools in many cities, with various weather patterns and temperatures, various city water chemistries, and all brands of pumps and filters, and concluded that the best time to run the pump is…

as long as possible!

In a perfect world, you want to run the pump 24-hrs a day. However, local power companies are not the friendliest when it comes to billing you.

So, here are the recommended times to run your pool pump:

Why do you need to run your pump?

Picture of Pool Pump

There are two really big reasons you will always want to know about pumps and their purpose…

1) Filtration:

You need to circulate water through the filter so dirt, pollen, and any other nasty particles that happen to land in your pool are removed and nothing messes up the pool water.

2) Sanitation:

You need to circulate sanitizer (chlorine) throughout the pool to kill microorganisms. If any microorganisms get into the water, they can create problems with the water chemistry, algae can start forming, or worse… the water can become toxic to swimmers. Unless you have a Smart Chemistry or Pool automation system to manage your circulation, you need to stay on top of things.

Stagnant Water is the Enemy!

Now, if your pool pump only runs 8-hrs daily, what happens for the other 16 hours? The water just sits there offering a perfect storm of potential microorganism and particle buildup. This is not good!

Filtering smaller particles throughout the day is so much less work and way more efficient for the filter vs a large amount of junk coming in all at once.

Additionally, if your pool water has sanitizer equally circulated throughout the water, and there are no stagnant zones for microorganisms to seek out, the sanitizer works smarter and not harder, and keeps things from ever getting started.

The solution is always circulation!

But, “how long to run the pump?” is the question that yields so many conflicting answers when doing your Google search.

And yes, we know it’s frustrating to find so many conflicting answers!

So, in order to figure out…

Here are the TWO most important things you need to know first…

1. What is my Pump’s Flow Rate?

This is determined by how many gallons per hour (GPH) or gallons per minute (GPM) it can circulate at high-speed. You typically can find this by looking on the side of your pump or referencing the operations manual or manufacturer’s website. e.g. 80 GPM

 

AND…

 

2. How Many Gallons in My Pool?

To figure this out, there are a couple ways to get the number.

Before you try doing any math or use a pool calculator, you can get a quick and easy rough estimate of pool volume by checking out the chart below.

Otherwise, the formulas are as follows:

Constant Depth Pools

These are square or rectangular will be Length x Width x Depth x 7.5. This will give you total volume in gallons. e.g. 12 x 24 x 6 x 7.5 = 12,960.

Round Pools

These have constant depth, or if you can find average depth, you just need to multiply Pi by the radius squared, by the depth, by 7.5. e.g. 3.14 × r2 × D × 7.5 = V (in gallons)

Variable Depth Pools

These have a shallow end and the deep end, typically have a gradual slope, which yields an average depth between shallow and deep ends. e.g. Shallow end is 3 feet and deep end is 9 feet, the average between the two is 6 feet. That’s the number you use for calculation.

 

Now, do the math…

What is the Minimum Circulation Required for my Pool?

Now that you have these two pieces of info, you can figure out how long it will take for your pump to fully circulate your pool water.

Just take the total gallons of your pool and divide by the pump’s GPM. e.g. 12,960 / 80 GPM = 162-minutes, which is 2.7 hours.

Add a little bit more time (15-minutes) to give your pump a little buffer of start-up time when it first starts flowing any stagnant water.

The calculated time above, plus another 15-minutes would be the minimum amount of time per day you want to circulate your pump on high-speed. In this case, it would be 2.95-hours.

NOW… back to the question…

How Long Should I Run My Pool Pump?

FOR VARIABLE SPEED PUMPS…

Best time to Run your Variable Speed Pump

Run your VS pump on high-speed for the Minimum amount of time for full circulation. e.g. 4-hours at night;

Then, run the pump on low speed for the rest of the day.

2nd Best time to Run your Variable Speed Pump

(Peak/Off-Peak Hours Considered)

Run your VS pump on high-speed for the Minimum amount of time for full circulation. e.g. 4-hours at night, during off-peak hours;

Keep pump off during peak hours;

Then, run the pump on low-speed for the rest of the day, during off-peak hours.

FOR SINGLE SPEED PUMPS…

Best time to Run your Single Speed Pump

Run your single-speed pump for the Minimum amount of time for full circulation. e.g. 4-hours at night;

Then, run the pump for 1-hour in the morning, around 8am;

1-hour early afternoon, around 2pm;

and 1-hour in the evening, around 6pm.

2nd Best time to Run your Single Speed Pump

(Peak/Off-Peak Hours Considered)

Run your single -speed pump on for the Minimum amount of time for full circulation. e.g. 4-hours at night, during off-peak hours;

Keep pump off during peak hours;

Then, run the pump at 1hr durations, spread throughout rest of the day, during off-peak hours.

What is the Best Way to Control My Pump?

Hands

You can use good old fashion hands to turn things on and off at the recommended times if your pump does not have a timer.

Timers

If your pool system doesn’t have a timer, standard wall mounted pool system timers will work well for basic settings if the pump does not have build in scheduling.

Built-In Pump Timer

If your pump has built in scheduling, you can use this method as well. VS Pumps should allow you to set the speed of flow in addition to scheduled time on and off.

Pool Automation

And last, but not least is a pool automation system, similar to the one we offer. Any decent pool automation system should have timers, scheduling and pump controls of some sort built into it.

Talk to your pool pro to figure out what you have if you currently have one installed. This way, you can get your pump on the correct schedule and avoid wasted energy and setup the most optimal schedule.

Conclusion

Anyways, we hope the pump info was useful. We have been testing the pump schedule theories for some time now and found that the above recommendations should get you setup for success.

And hopefully, we answered the infamous question, “How Long Should I Run My Pool Pump?”