Pool Heating Systems

Determine whether a gas, electric, solar, or geothermal pool heating system is right for your swimming pool.

By Kimberlee Courtney


Gas pool heaters use natural gas or propane and can heat a large volume of water relatively fast, making them great for large pools and those not used on a daily basis.  Gas heaters can also maintain a set temperature, which is great if you live in a chilly region. They have a higher operating cost than other types of heaters, but that can be reduced by using a pool cover or a secondary pool heating system once the desired temperature is reached. 

Electric pool heaters, or heat pumps,  transfer heat from the outdoor air to the pool water via a heat exchanger. They work best in mild climates where the margin between the air temperature and desired water temperature is small and the outside temperature remains above 45 – 50 degrees F. Electric pool heaters take a little longer to heat the water and must run continuously to maintain an even flow of warm water; they are more cost effective for frequently used pools than gas heaters.  

Geothermal/ground-source heat pumps transfer heat from the ground to the water in your pool via antifreeze-filled pipes that are buried in the ground. Unlike air-source heat pumps, ground-source heat pumps are unaffected by colder temperatures during the winter months; therefore, they can be used year round. (If you live in a colder region, however, you’ll need a larger area of land to install this system.) 

Solar pool heaters consist of large black panels that are installed on the roof of the home, pool house, or other adjacent structure. Direct (open-loop) solar pool heating systems should be used in warm climate regions that do not have freezing temperatures. Indirect (close-loop) systems can reach higher temperatures than direct systems, making them a better fit for colder locations.

Photo courtesy of Kevin Woodhurst