Sizing Your Heat Pump Pool Heater

Learn how to size your swimming pool heat pump so that you can get the right size heater for your pool.

SIZING YOUR HEAT PUMP POOL HEATER

The most important thing about purchasing a pool heat pump is determining the correct size for your above ground pool.

Determining the correct size will save you money as a heat pump with the correct amount of BTUs will limit the overall run time and reduce your electric bill throughout the season. More importantly, throughout the colder months when you would like to use your heat pump the most, you will shorten the overall heat time of your pool and in turn also limit the amount of electricity required to run the unit.

It is also important to know that there is a difference between an electric heat pump and a natural gas or propane heater. Natural gas and propane heaters require a higher amount of BTUs compared to electric heat pumps for the same size swimming pool.

Electric Heat Pumps

Our heat pumps are the perfect solution for extending your swimming season and keeping your pool water warm.

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Pool Heaters

Look for your pool size below on the Heat Pump Sizing Chart to find the correct amount of BTUs for your pool. More BTU’s means more power, more heat transfer, quicker results and less operation time.

Basic Principles for Sizing Heat Pump

  • Size at 4 BTU's per gallon of water - To heat a pool in normal summer conditions when the ambient air temperature average is 70°F in a 24 hour period. For example, if your swimming pool is 10,000 gallons then you should purchase a heat pump with a minimum of 40,000 BTU's.
  • Size at 5 BTU's per gallon of water - To heat a pool in spring and fall conditions when the ambient air temperature average is 60°F in a 24 hour period.
  • Size at 6 BTU's per gallon of water - To heat a pool in extended spring and fall conditions when the ambient air temperature average is less than 60°F in a 24 hour period.

Swimming Pool Sizing Chart - ROUND

Pool Size (Feet) Summer
4 BTU/Gallon
Spring & Fall
5 BTU/Gallon
Extended Season
6 BTU/Gallon
Up To 21' Round
50,000 BTU50,000 BTU65,000 BTU
Up To 24' Round
50,000 BTU65,000 BTU85,000 BTU
Up To 27' Round
65,000 BTU85,000 BTU110,000 BTU
Up To 30' Round
85,000 BTU110,000 BTU125,000 BTU
Up To 33' Round100,000 BTU125,000 BTU150,000 BTU

Swimming Pool Sizing Chart - OVAL

Pool Size (Feet)
Summer
4 BTU/Gallon
Spring & Fall
5 BTU/Gallon
Extended Season
6 BTU/Gallon
Up To 15'x26 Oval
50,000 BTU50,000 BTU65,000 BTU
Up To 15'x30' Oval50,000 BTU65,000 BTU85,000 BTU 
Up To 18'x33' Oval
65,000 BTU85,000 BTU 110,000 BTU 
Up To 18'x40' Oval
85,000 BTU110,000 BTU 125,000 BTU
Up To 21'x43' Oval
100,000 BTU125,000 BTU150,000 BTU

Swimming Pool Sizing Chart - BY GALLONS

Capacity
Summer
4 BTU/Gallon
Spring & Fall
5 BTU/Gallon
Extended Season
6 BTU/Gallon
Up To 10,000 Gallons
50,000 BTU50,000 BTU65,000 BTU
Up To 13,000 Gallons50,000 BTU65,000 BTU85,000 BTU
Up To 17,000 Gallons
65,000 BTU85,000 BTU110,000 BTU
Up To 21,000 Gallons85,000 BTU110,000 BTU125,000 BTU

We recommend the use of a solar pool cover in addition to your heat pump. Keeping the solar cover on your swimming pool during the nighttime hours will help prevent heat loss and chemical dissipation.

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