Should a Pool Pump Run Continuously?


I certainly wondered should I leave my pool pump on all the time when I first had a pool. I knew it was important that the water in the pool was kept clean but was unsure whether a pool pump should run continuously or not.

There is no need to run a pool pump continuously for 24 hours a day, with a few exceptions. It is normally recommended that your pool pump should run long enough to pump the entire volume of water in a pool each day. In practice, this generally means around 8 hour each day.

If you ran the pump continuously it would largely be a waste of electricity (and give a big electricity bill) and it would also wear out your pool pump far earlier than necessary.

Having said that, if money isn’t an issue to you, then by all means run the pool pump for twenty four hours a day. Your pool will definitely stay cleaner if the water is constantly being filtered.

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How long should I run my pool filter each day?

How long should I run my pool filter each day?

It is an established rule of thumb that the minimum time you should run the pump for is sufficient time for the all of the water in the pool to be filtered once. Often this is around 8 hours per day.

Pool constructors often supply a pool pump with a flow rate to pump the full volume of the pool in 8 hours as a rule of thumb.

To work out how long this should be you need to know two things:

  1. The volume of water your pool pump can pump per hour (gallons per hour or liters per hour)
  2. What the volume of the water in your pool is

Flow rate of the pump

To find out the flow rate of your pump you need to look at the specification label on the pump itself. You should find a GPM (gallons per minute) figure. If you cannot find it then try looking for the specifications on the manufacturer’s website.

Volume of the pool

To work out the volume of water in your pool can be more complicated, particularly if you have an oval or odd shaped pool.

For an oblong pool with a constant depth it is easy. Just multiply the width by the length and then by the depth (in feet) to give the cubic feet of water. You then multiply this figure by 7.5 to give the volume in gallons.

Pools with varying depths, round pools, oval pools, kidney pools and other shapes makes it more complicated. Rather than turn this into a mathematics post, I suggest you look on your cell phone for an app which will help you calculate the volume of a pool. There are plenty to choose from.

Simple example

Should a pool pump run continuously?

So if the pool was 30ft x 15ft and 5 ft deep the volume in cubic feet would be 2250. There are 7.5 gallons in a cubic foot of water so this is then multiplied by 7.5 to give a volume of 16875 gallons. If the pump flow rate was 50 GPM that would be 3000 gallons per hour. So 16875 gallons divided by 3000 gallons per hour gives a figure of 5.625 hours (5 hours 37 minutes) to pump the entire volume of the pool. In this case I would probably set the timer for 6 hours.4

When should you leave pool pump running all time?

I did wonder when I first had a pool whether there are any situations where should I leave my pool pump on all the time. Well there are a number of situations where you may want to do this. These include:

  • If you have given the pool a big dose of chemicals then you may want to leave the pump running for 24 hours or so to ensure the chemicals are spread around the pool.
  • If the pool is cloudy then running the pump until it clears would be worthwhile.
  • If the pool will get lots of use, if you have friends staying perhaps, particularly if they include children who are in and out of the pool all day.
  • If in winter you haven’t winterized your pool and there is a very cold spell forecast then you should leave the pump running to stop the water in the pipework freezing.

Is it better to run a pool pump at night or day?

In many places the cost of electricity is supplied at a cheaper rate at night than during the day. So running the pump at night can make the costs of running the pool less. But there is more to this than pure economics so consider these factors:

  • A pool is generally most vulnerable to attacks by algae during the day as it needs light to grow. Only running a pool at night increases the risk of algae. So ideally you want the chlorine circulating at a time when the algae is most active – so during the day.
  • Your pool will get most of its use during the day so really you need the pump running to keep the pool clean while it is being used and also for the chlorine to do its job properly.
  • If you have solar heating that requires a water flow through it to absorb the heat of the sun then obviously running the pump only at night will not heat the pool up at all.
  • If your pump is at all noisy and you have close neighbors then they not be too happy hearing the pump whirring all night. It would certainly annoy me as I am a light sleeper. In fact, my neighbor’s pool is the other side of the fence from my bedroom and, although I can’t hear his pump, I get woken up at 7am each morning when his waterfall starts. I am not an early riser so that doesn’t please me (but unfortunately he is an unhelpful idiot so if I spoke to him about it then he would just set the timer to come on at 5am!)

Will a variable speed pool pump save me money?

Having a variable speed pool pump will certainly save you money in the long run as when it is running at a lower speed it will consume less electricity. In many instances savings are in excess of 50% so even with the increased cost of buying the pump initially it is easy to see that this cost will soon be recovered.

If your existing standard pool pump is quite old then it is likely to be pretty inefficient too. So even if you were to run the variable speed pump on full for the same amount of time as the old one you will save money as new variable speed pumps are more efficient. But using the new pump at a lower speed at certain times will save even more.

The generally accepted best variable speed pump is the Pentair 011018 IntelliFlo Variable Speed High Performance Pool Pump which can save up to 90% over standard pumps. It is quite a large investment but will pay for itself over time.

How long should you run a pool pump in winter?

The length of time you should run a pool pump in winter rather depends on the climate where you live. It is different if you live in a cold climate or a warmer one.

How long should you run a pool pump in winter?

If you live somewhere that can reach low temperatures and the water could freeze, then during those cold periods you really need to either winterize the pool or when the temperature may drop below freezing, run the pump to ensure the water in the pool and the pipes does not freeze.

If you have a variable speed pump then some of these have a winter setting which turns the pump on when the temperature falls to a particular level.

Where I live the minimum winter temperature at night is around 52 degrees Fahrenheit / 11 degrees Centigrade (yes I know, poor me) so I just leave the pump on an 8 hour timer all the time.

Of course, the above assumes that you do not close your pool for the winter by lowering the water level and draining the pipework, pump, filter etc. If you do then the pump should not be run since there will be no water in the system.

If I use a pool cover will that affect the time the pump should run?

Yes it will to some extent. As discussed above, light is an important factor in the growth of algae. So if you have a pool cover on, which are generally a dark blue, then less light shines on the water so algae will be less likely to grow. Therefore, in theory you could run the pool pump for less time.

In practice I rarely reduce the time the pump is on when I have my pool cover on (which is mainly in the spring and autumn to help keep the warmth in).

Can you swim while the pool filter is running?

Can you swim while the pool filter is running?

Yes you can, and I would even say it is better to run the pool pump while you are swimming in fact.

If the pump isn’t running then the skimmers will not be operating. You are therefore more likely to have debris (leaves, insects etc) floating on the surface of the pool which you don’t really want when swimming.

Also, people swimming bring contaminants into the pool with them such as:

  • dirt, sand and dust on their feet
  • deodorant on their bodies
  • suntan lotion perhaps
  • hair

So having the pool pump running means the filter will be able to deal with these as quickly as possible.

Should I run my pool pump when it rains?

Unless there is any chance of a thunderstorm then running the pump when it is raining won’t really matter one way or the other. Potentially there could be contaminants in the rain so these might be removed more easily if the pool pump is running.

It is not something to worry about. After all, the pump is likely to be on a timer, so if it is running during the day while you are at work and it starts to rain (or there is even a thunderstorm) what are you going to do? Go home to switch off the pump? I guess that in these days of “smart” devices there may be a way to switch your pool pump off using your cellphone but I haven’t seen one.

After heavy rain it is good practice to shock the pool once it stops.

How long can a pool go without a pump?

If your pool pump breaks then obviously the water will no longer flow and be filtered. So from that moment onward the water quality is likely to deteriorate. If you leave it like this for a long period of time then you may end up with the dreaded green pool but for just a few days it won’t be a problem.

If you intend swimming in it while the pump is broken then I would suggest that you test the water quality first with a test strip or whatever method you use.

My top three pool cleaning tools to make life easier

Dolphin Nautilus CC Plus Robotic Pool Cleaner – the best time saving product on the market. I have never heard anyone say they regret buying one.

Hayward Poolvac Leaf Canister – very useful when leaves are a problem in your pool

Aquatix Pto Pool Step & Corner Vacuum Head – I use this every time I vacuum my pool. It gets where other vacuum heads can’t.

FAQ

How long do pool pumps last?

This is a “how long is a piece of string?” type question. It depends on the type and quality of the pump, the amount it is used and how well the system is maintained. But a rough rule of thumb is that a pump can last for anything from 7 years to upwards of 12 years. I recently replaced my pump and as far as I can establish it was at least 12 years old.

Can you run pool pump with cover on?

It is absolutely safe and, in fact, completely normal to run a pool pump while a solar cover is still on. The water will circulate as normal and be filtered while still retaining heat.

JP in Fuerteventura

I have had hot tubs for many years and a pool for the last 7 years. I had to learn how to clean it, maintain it and fix it the hard way. Since then I have helped many friends and neighbors with their pools and now I want to share everything I have learned with you.

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