Pool Heat Pumps

What size pool heat pump do I need?

Pool heat pump sizing is based on pool volume and your climate. A general rule: multiply your pool's gallons by 8.34, then divide by 24 to get the BTU/hr needed for a standard heat-up in moderate weather. For a 15,000 gallon pool in a moderate climate, that works out to roughly 70,000 BTU. In cooler climates like the Northeast or Midwest, size up one tier. Use the sizing calculator above for a precise estimate based on your specific pool and location.

How long does a pool heat pump take to heat a pool?

A correctly sized pool heat pump typically raises water temperature by 1 to 2 degrees Fahrenheit per hour. For a pool starting at 60 F and targeting 82 F, expect 12 to 24 hours with a standard unit and the right BTU rating. Inverter models running continuously can be faster. A pool cover dramatically speeds this up by preventing heat loss overnight - it can cut heat-up time nearly in half.

Do pool heat pumps work in cold weather?

Pool heat pumps extract heat from the surrounding air, so their efficiency drops as air temperature falls. Most units operate effectively down to 45-50 F air temperature. Below that, output decreases significantly. In cold climates, this means heat pumps work well from May through October but are not practical as a year-round solution without supplemental heating. For year-round swimming in cold climates, a cold-weather-rated inverter model like the Madimack InverTitan or InverELITE (rated to 14 F) is a better fit.

What is the difference between an inverter and a standard pool heat pump?

A standard pool heat pump runs its compressor at full power and cycles on and off. An inverter pool heat pump uses a variable-speed compressor that adjusts output continuously to match demand - running at lower power when the pool is close to temperature, higher power when it needs to catch up. Inverter models use 20 to 40% less electricity over a season, run significantly quieter, and typically last longer because the compressor experiences less wear from hard start/stop cycling. The tradeoff is a higher upfront price, usually $500 to $1,500 more than a comparable standard unit.

How much does it cost to run a pool heat pump?

Running costs depend on pool size, target temperature, climate, and whether you use a pool cover. For a typical 15,000 gallon inground pool in a moderate climate, a standard heat pump costs roughly $80 to $130 per month during swim season. An inverter model for the same pool runs closer to $50 to $95 per month. Year-round in a warm climate like Florida, annual running costs typically range from $300 to $600 for an inverter unit. Gas heaters cost 3 to 5 times more to operate at current energy prices.

Can a pool heat pump heat a spa or hot tub?

Yes, with some caveats. Most GulfStream, AquaCal, Hayward HeatPro, and Madimack models in this collection are rated for pool and spa use - look for the Spa tag in the table above. The FibroPool models are not included in that group, as they are designed specifically for pool use and their flow rate requirements may not align with standalone spa circulation systems.

The main practical consideration for spas is recovery speed. Heat pumps raise water temperature at 1 to 2 degrees F per hour, which works well for maintaining a spa that's already at temperature but is slow for heating a cold spa from scratch. If you want a spa that can go from cold to hot in under an hour on demand, a gas heater is a better fit for that specific use case. For pools with attached spas where both are kept at temperature together, a correctly sized heat pump handles both efficiently.

What size pool heat pump do I need?

Pool heat pump sizing is based on pool volume and your climate. A general rule: multiply your pool's gallons by 8.34, then divide by 24 to get the BTU/hr needed for a standard heat-up in moderate weather. For a 15,000 gallon pool in a moderate climate, that works out to roughly 70,000 BTU. In cooler climates like the Northeast or Midwest, size up one tier. Use the sizing calculator above for a precise estimate based on your specific pool and location.

How long does a pool heat pump take to heat a pool?

A correctly sized pool heat pump typically raises water temperature by 1 to 2 degrees Fahrenheit per hour. For a pool starting at 60 F and targeting 82 F, expect 12 to 24 hours with a standard unit and the right BTU rating. Inverter models running continuously can be faster. A pool cover dramatically speeds this up by preventing heat loss overnight - it can cut heat-up time nearly in half.

Do pool heat pumps work in cold weather?

Pool heat pumps extract heat from the surrounding air, so their efficiency drops as air temperature falls. Most units operate effectively down to 45-50 F air temperature. Below that, output decreases significantly. In cold climates, this means heat pumps work well from May through October but are not practical as a year-round solution without supplemental heating. For year-round swimming in cold climates, a cold-weather-rated inverter model like the Madimack InverTitan or InverELITE (rated to 14 F) is a better fit.

What is the difference between an inverter and a standard pool heat pump?

A standard pool heat pump runs its compressor at full power and cycles on and off. An inverter pool heat pump uses a variable-speed compressor that adjusts output continuously to match demand - running at lower power when the pool is close to temperature, higher power when it needs to catch up. Inverter models use 20 to 40% less electricity over a season, run significantly quieter, and typically last longer because the compressor experiences less wear from hard start/stop cycling. The tradeoff is a higher upfront price, usually $500 to $1,500 more than a comparable standard unit.

How much does it cost to run a pool heat pump?

Running costs depend on pool size, target temperature, climate, and whether you use a pool cover. For a typical 15,000 gallon inground pool in a moderate climate, a standard heat pump costs roughly $80 to $130 per month during swim season. An inverter model for the same pool runs closer to $50 to $95 per month. Year-round in a warm climate like Florida, annual running costs typically range from $300 to $600 for an inverter unit. Gas heaters cost 3 to 5 times more to operate at current energy prices.

Can a pool heat pump heat a spa or hot tub?

Yes, with some caveats. Most GulfStream, AquaCal, Hayward HeatPro, and Madimack models in this collection are rated for pool and spa use - look for the Spa tag in the table above. The FibroPool models are not included in that group, as they are designed specifically for pool use and their flow rate requirements may not align with standalone spa circulation systems.

The main practical consideration for spas is recovery speed. Heat pumps raise water temperature at 1 to 2 degrees F per hour, which works well for maintaining a spa that's already at temperature but is slow for heating a cold spa from scratch. If you want a spa that can go from cold to hot in under an hour on demand, a gas heater is a better fit for that specific use case. For pools with attached spas where both are kept at temperature together, a correctly sized heat pump handles both efficiently.