A common question that consumers ask us at AquaCal when shopping for swimming pool heat pumps is: How big does my heat pump need to be? You should have a trained swimming pool professional size your swimming pool heat pump, as its size will depend on many factors. There are, however, general formulas we provide to our customers to approximate heat pump size. We explain how to use these formulas in this article.
Heat pumps are sized according to required BTU (British Thermal Unit) per hour of the swimming pool. Consumer often make the mistake of purchasing under-sized units units with insufficient BTU output per hour. Under-sized units must run longer in order to heat swimming pools. These longer run times translate to decreased efficiency and higher operating costs. Use the following instructions to approximate the BTUs per hour your heat pump will require.
- Determine your desired water temperature in °F.
- Determine the average air temperature of the coldest month during which you plan to use your swimming pool in °F.
- Subtract the average air temperature from your desired water temperature to calculate the required temperature rise.
- Calculate the surface area of your swimming pool in ft2:
- Circular pools: radius x radius x 3.14
- Kidney-shaped pools: length x width x 0.75
- Oval-shaped pools: (0.50 x length) x (0.50 width) x 3.14
- Rectangular pools: length x width
- Calculate the required BTU output per hour: surface area x temperature rise x 12
In addition to these instructions, we at AquaCal provide our customers with a free cost estimator program. This program takes only minutes to complete and will provide you with recommendations on the size of heat pump you need to efficiently heat your swimming pool. To access this free program, click here. If you need additional help, one of our dealers will be happy to assist you in determining the right size heat pump for your swimming pool! Click here to find a dealer nearest you.
By following these steps, you can quickly and easily approximate your required heater size. Remember, however, that only a licensed swimming pool professional can perform a proper sizing analysis! If you have any questions or concerns about heat pump sizing, feel free to leave a comment below or contact us at AquaCal directly.