Gas pool heaters use the combustion of either natural gas or propane to heat pool water. As the water is circulated by the pump, it passes through a filter then to the heater. The gas burns inside the heater’s combustion chamber, generating the heat that’s absorbed by the water as it returns to the pool. Unlike an air-source heat pump, a gas heater does not rely on ambient air temperature, which means it can effectively heat a swimming pool even at low temperatures. As such, gas pool heaters are the best option for homeowners who want their pool water warm all throughout the year.
Gas heaters also typically produce more BTUs (British Thermal Units) per hour than their air-dependent counterparts, a feature that allows them to heat swimming pools relatively faster.
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