Your above ground pool pump is the heart of your pool’s water circulation system. No pump, no water moves, period. We all know that, but what else do we need to know when making a decision about what type and size of pool pump is best for your above ground pool infrastructure?
How Does a Pool Pump Work?
One important aspect of your pool pump is that it cleans your water by circulating it through filters. The rule of thumb is that a pump should be run long enough to circulate the entire volume of water in your swimming pool each day. On days of heavy usage, such as during a pool party, you would want to run the water through your filters twice. By comparison, a commercial or public pool would run all of its water through the filters many times per day. So how do you determine how long your pump has to run to filter your swimming pool water properly? That is where some simple math comes into play.
Let’s say your above ground pool holds 20,000 gallons of water, and your pump can move 50 gallons of water per minute. That means your pump can move 50 x 60 minutes = 3000 gallons of water per hour. Divide 20,000 by 3000 and it would take your pump 6 hours and 40 minutes to filter the entire pool. That is called the turnover rate.
By the way, an easy way to calculate the gallon capacity of your above ground swimming pool can be found here.
What Capacity of Pump for Your Pool Size?
I have read many websites about pool pump size and have discovered some variance of opinion. Some sites claim that pool retailers will upsell a pump that is 1.5 to 2 hp because bigger is better, right? Not necessarily. Not included in the math above are two other numbers associated with pool pumps; minimum turnover rate and maximum flow rate. These parameters within which the manufacturer represents your pump can operate.
Minimum Turnover Rate / Maximum Flow Rate
Minimum turnover rate is how long it takes to turn over your pool water. Let’s say you have a 15,000 gallon pool.If you desired to turn over your water every 6 hours, it would take a 50 GPM (gallon per minute) pump capacity. Every 8 hours would take a 31 GPM pump, and for a complete filtration cycle of 10 hours it would take a 25 GPM pump.
Your maximum flow rate in GPM (gallons per minute) is determined by the entire system, not just the pump. The equation considers the maximum flow in GPM based on plumbing size (diameters of the pvc lines) and water velocity, which is impacted by suction side (the line going into the pump) in FPS (feet per second) and return side (the line exiting the pump) in FPS.
Hayward is considered the gold standard for pool pumps and heaters. Click to see their powerpoint about the mechanics and formulae of water circulation. It contains some great information and I think that it will be time well spent for prospective pool owners.
Difference of Opinion
Some experts do not like the 8 hours on / 16 hours stagnant circulation cycle that is supported by some many others and referenced on this page. The supporters of running your pump 24/7 claim that in reality, when the stagnant state is in effect, that is when algae, ph swings, and debris buildups will occur. These are all negative developments, to be sure. The rest of the argument is that if you have sized a pool pump small enough in hp that will circulate the entire amount of water in your pool over 24 hours, it will be less costly than using a bigger pump over 8 hours. There is chart from ThoughtCo that you should take a look at. It certainly expanded what I thought was a done deal as far as matching and operating a pool pump in my future above ground pool. In conclusion, while the remainder of my article assumes 8 on/ 16 off operation, I’ll am saying it with an asterisk in place, ok 🙂
By the way, one should check their local bylaws or state / provincial laws regarding operation of pool pumps. California passed Title 20 in order to support energy conservation. They are a high pool density state with 1.5 million swimming pools, and if all pools were pump efficient that could eliminate the equivalent need for 4 power plants! California now requires all pool pumps to be variable speed because they are so much more efficient. The state government even offered subsidies to help pool owners switch over to the much cheaper, energy and efficient variable speed pumps. Here is a quick overview of the California environmental effort.
Three Types of Pool Pumps
The three types of pool pumps are the single speed, the dual speed, and the variable speed. Basically, the differences between the three types are in upfront purchase price (cheapest in order : single speed, dual speed, variable speed). Point two is the operational cost (cheapest in order : variable speed, dual speed, single speed). The third difference between the three is sound level, or noise generated. The noisiest is the single speed, followed by the dual speed, and both surpassed by the very quiet variable speed pool pump.
Pool Pump Examples
Here is one of their products that you can click on to read Amazon reviews and consider pricing. This single speed unit is rated at 4.5 stars out of 5 by 1,255 customer reviews! You can’t get much better than that!
The unit below is a variable speed. There are no customer reviews yet available on this pump but click on to discover it’s much higher pricepoint than the single speed pump above.
Pool Pump Efficiencies
Keeping your pool pump operating efficiently includes what you can do to ease the work burden on the pump. This will keep your pump from wearing out and needing premature repair or replacement. You also want your pump to do it’s job and keep the water circulating in your pool to keep it clean, warm, and healthy. Pool pump efficiency also considers how to do this at the lowest recurring financial cost for electricity. Similar to solar power optimization , there are many easy steps that you can implement.
- Clean your drains on a routine basis – debris will accumulate around your pool drain leading to the pump. Blocked drains cause the pump to work harder to do it’s job, and it takes more electricity to do it. This easy maintenance will save both on pump life and daily operational electrical cost.
- Install a pool cover – follow the link to the section explaining how a pool cover will go a long way to saving you money and energy. Evaporation is the enemy of pools. Not only can a pool lose thousands of gallons of water in evaporation each season which costs you money to replace. It also costs you in the chemicals that evaporate along with the water. Remember that the heat your pump worked hard to distribute to bring your swimming pool up to a nice temperature for you is gone along with the evaporated water. Do your pump and your pocketbook a favor and install a pool cover!
- Run your pump for less time – Your pool pump should run for approximately 8 hours per day if it is properly matched for the size of pool. If your pump is running for a longer period than that, consider experimenting to reduce that time. A well managed pool takes into consideration minimizing the operational time of it’s pool pump.
- Keep your filters clean – just as you keep debris from your pool drains, so should you clean your pool’s filters. As they do their job pool filters will accumulate debris and grime slowly over time. This makes them less efficient to continue to do their job at filtering contaminants from your water. It also makes your pump work harder as the accumulation also serves as blockage in the system. Pool sites suggest a weekly review of the state of your filter.
A really good idea for saving money is to set your pump timer to operate in non-peak consumption hours. This would typically be at night from around midnight to the early hours of the morning. Check your electricity provider to find the cheapest consumption hours in your community. You will not use and less energy, but you will pay less for what you use if your local utility company has off hours rates.