How to Calculate What Size Heat Pump to Use for Swimming Pools
- 1). Decide how warm you want your pool water to be. Most people prefer a temperature in the high 70s or low 80s (Fahrenheit), but your individual taste may vary.
- 2). Determine the average temperature during the coldest month you wish to use the pool. You can usually do a quick estimation based on your own experiences, but if you want formal numbers, check the National Weather Service for average temperatures in your area.
- 3). Subtract the ideal temperature of the pool water from the average outside monthly temperature. The result is the number of degrees Fahrenheit your heater will need to warm the pool in order to make it comfortable.
- 4). Calculate the surface area of your pool. If you have a rectangular pool, this is easy: simply multiply the pool's length by its width. If your pool has a more unusual shape, apply the formula provided at PoolBright.com (see Resources, below).
- 5). Multiply the surface area from Step 4 by the required elevation in pool temperature from Step 3. Then multiply the results by 11. That figure is the number of British Thermal Units per hour (btu/hr.) your heater will need to produce in order to adequately heat your pool.
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