Choosing a Pool Pump
Calculate the size of your pool
- Measure your pool's width, length and (water) depth in feet, using decimals to approximate fractions of feet. (In other words, 20 feet, 3 inches would be 20.25 feet.)
- Multiply the length of your pool by its width to determine its surface area.
- Multiply the pool's surface area by its depth, and multiply the result of this by 6.25 (rectangular pools) or 4.9 (circlar pools) to determine how many gallons of water your pool holds
e.g. Rectangular Pool 24 foot pool x 12 foot x 4.5 foot = 8,100 gallons
Circular Pool 18 feet x 18 feet x 4.5 feet = 7,745 gallons
Determine the Minimum Flow Rate for your Pool
- Divide the number of gallons of water your pool holds by 8.
- Then, divide the result by 60.
- This will determine the minimum flow rate you need from a pump to ensure the water in your pool can make a complete circulation every 8 hours.
- e.g. Rectangular Pool 24 foot pool x 12 foot x 4.5 foot = 8,100/8 = 1013 gallons per hour
Circular Pool 18 feet x 18 feet x 4.5 feet = 7,745/8 = 968 gallons per hour
Determine the maximum flow rate your pool can handle by looking at its plumbing system.
- A 1.5-inch pipe system can handle upto than 2700 gallons per hour
- Most pools use 2-inch pipes, which can handle about 4380 gallons per hour.
- A 3-inch pipe can handle more than 9000 gallons per hour.
- Use a slightly lower flow rate if your plumbing has a lot of intricate turns and connections that could be stressed by too much rushing water.
- Select a pool pump with a flow rate between your minimum and maximum allowance.
- e.g. Rectangular Pool 24 ft x 12 ft x 4.5 ft needs a pump between 1013 and 2700 gph (1.5" pipes) or 1013 and 4380 gph (2" pipework)
