Pool Heater Size Calculator

How It Works

Pool heaters come in three types: gas heaters heat water fastest and work in any temperature but cost the most to operate. Heat pumps are 5-6 times more efficient than gas (they move heat from the air rather than creating it) but work poorly below 50 degrees F and heat more slowly. Solar panels are essentially free to operate but depend on sun exposure and climate. The single most effective way to reduce heating costs is a pool cover — an uncovered pool loses 70% of its heat through surface evaporation. A simple solar cover costs $50-100 and can cut heating bills in half. Size your heater for the coldest conditions you plan to swim in.