You might be a lot like me. I often overkill and over-design everything instead of taking the time to work out the required amount. Running a pool pump is no exception. But, is running your pool pump around the clock financially sustainable? Let’s find out if we can save some cash by putting our laziness aside, and taking the time to find out exactly how long our pumps should be running during the day.
The minimum requirement is to cycle the full volume of pool water once a day, and most pools are designed so that the pump can cycle all the water in the pool within 8 hours. So running your pool pump 8 hours a day is a good starting point.
Your pump should run long enough each day to cycle the full amount of water that is in your pool. This is referred to as the “turnover time” If you have a large pool with a small pump, then you will need to run your pump for longer. If you have a smaller pool with a larger pump, your running time is going to be less.
Let’s go through the calculations and work out exactly how long you should be running your pump every day using the volume of your pool and the flow rate of your specific pump.
How to Calculate You Pool’s “Turnover Time”
The “turnover time” of your pool is the amount of time it takes for your pump to cycle the full volume of water that is in your pool. To calculate your “turnover time” we need two figures, your pool’s volume in gallons, and your pool pump’s “flow rate”.
How to calculate your pool’s water volume (with a calculator)
There are many reasons to know the volume of water that is in your pool. You will need this figure to calculate what quantities of chemicals to add to your pool, how much refilling your pool will cost, and in this case, to calculate the “turnover time” of your pool. So write this number down and don’t lose it.
You can either work out the volume by yourself by using basic math (or not so basic for some of us), or you might find this calculator useful to do the job for you. I am lazy by nature, so I will opt to use the calculator.
Click here to use the pool volume calculator (opens in new window)
Ok, I am back with the results. My pool is 9ft wide by 16ft long, and 4ft deep at the shallow end, 10ft deep at the deep end. So my pool is approximately 10,800 gallons.
Once you have the volume of your pool, we know how much water needs to be pumped daily. In my case, I need my pump to cycle 10,800 gallons of water each day.
The next thing I need to know is how long it will take for my pump to cycle that amount of water, which is my pool’s “turnover time”. I now need to find my pump’s “flow rate”.
How to find your pumps “flow rate”
Before we get stuck into this, we want to make sure that the pump can get the job done in less than 10 hours. In other words, the pool’s “turnover time” needs to be less than 10 hours. If the “turnover time” is more than 10 hours, then we should consider upgrading our pump.
To calculate the turnover time, we need to know the rate at which your pump can drive water. This is known as the “flow rate” of the pump and is measured in Gallons per Hour (GPH).
Finding the flow rate for your specific pump is very easy. The flow rate is usually specified on the packaging and user manuals of the pump. If you don’t have the packaging or manuals anymore, simply go to your pool pump manufacturers’ website and check the specifications. Use a search feature and look for “flow rate”.
When you find the specs, you’ll notice two flow rates; “pump flow rate” and “system flow rate”. Always use the system flow rate, as this is the final flow rate with the filtration system taken into account. (Filters, valves, cleaners, etc.)
Let’s use the 3000 Gph Krystal Clear Sand Filter Pump for example. This pump can cycle 2,450 Gallons per Hour.
And the “Turnover Time” is…. (drumroll please)
Wait, one more step, dammit…
Now we need to divide the volume of the pool (10,800 gallons) by the system flow rate (2,450GPH) and we get the turnover time of our system (4.4 hours).
See, that was easy, wasn’t it?
Not so fast! Now, I gotta tell you that this calculation is the best-case scenario based on a brand new pump with flawless plumbing and barely any bends in the line. Let’s be safe and give ourselves a 100% margin of safety by doubling the “turnover time”.
We get to 8.8 hours which is 8hours and 48 minutes. This is just about standard for most normal pools.
Now, if you have managed to get this far, give yourself a pat on the back.
But I know what you’re thinking. Why in the world did we just spend our precious time with stupid maths? We could just get a super-powerful pump and run it ten hours a day, and be done with it.
Yeah, you could do that, but we really have to consider the energy usage first. Just because you’re rich, doesn’t mean its right.
How Much Electricity Does My Pool Pump Use Per Hour?
After the air-conditioner, the pool pump is the highest energy-consuming appliance in the average household, and houses with swimming pools consume 49% more electricity than households without pools.
Based on the US National Average Price of Electricity of 12.85c/kWh, a standard 2hp pool pump using 2.25kW/h will cost you 28.92 cents per hour to run. If you run your pump for 8 hours daily, it would cost you $2.30 a day, or around $69.40 a month.
To put that into perspective, reducing your daily run time by one measly hour can save you around $105.56 per year. You could buy 120 beers with that!
So we can now clearly see why it is important to run your pump for only as long as you need to. For every hour of run time you save, just think about an extra 120 beers handed to you at the end of the year. It’s that real!
Conclusion
Technically speaking, there is nothing wrong with running your pool pump on overtime, heck you could even run it 24 hours a day if you like. The problem is that is isn’t financially feasible for most people, and it’s completely unnecessary. As a matter of fact, I believe that it is quite irresponsible, both financially and on the environment.
All you have to do is some basic calculations to find out the volume of your pool and look online to determine your pool pump’s “flow rate”. Using these two numbers, we can easily calculate the pool’s turnover time – the time it takes for your pump to drive the full volume of your pool’s water through the system.
If your turnover time is more than 10 hours, it would be a good idea to upgrade your pump and get the run-time down to 8 hours.
By saving one hour of run time, we are able to save $105 every year on our energy bill. That’s enough for 120 beers!
Sound’s reasonable to me…