Electric heat pumps use electricity to transfer heat to the swimming pool. Heat pumps work like a reverse style air conditioner, removing the heat contained in the air and transferring it to the water instead of releasing it. Although they add to your utility bills, electric heat pumps are known to be highly energy-efficient. Gas Heaters Gas heaters use propane or natural gas to produce heat. As these devices burn gas, water passes through a series of copper coils inside the combustion chamber and gets heated. Gas heaters have are seen wide use as swimming pool heaters in the past for the speed at which they can heat up
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