Best pool heater for Florida: heat pump vs solar vs gas

Florida pools do need heat, just not for long. Winter is when the water gets too cool for comfortable swimming, and a heater stretches the season through those months. For most Florida homeowners who heat for weeks at a time, an electric heat pump or solar collectors are the best pool heater, because they cost the least to run. Gas wins when you heat only now and then and want the water warm by this afternoon. This guide compares the three on installed cost, running cost and lifespan, plus the Florida rules for solar.

How much heat a Florida pool needs

The Florida Solar Energy Center (FSEC) has studied this for decades. Its guide to sizing solar pool heaters in Florida treats 78-80°F as comfortable in spring and fall and 76°F in winter, and notes that most of the state’s pools need winter heating. Those targets are modest. You aren’t heating a spa, you’re keeping the pool from dropping into the 60s.

Fixr says most pools need roughly 85,000 to 200,000 BTU of heater capacity to stay comfortable. The right size depends on the pool’s surface area, how warm you want it and how cold your nights get. Have the installer calculate it for your pool rather than picking a unit from a chart.

The three options at a glance

	Heat pump	Solar	Gas (natural gas or propane)
Installed cost	$2,500-$6,500	$2,500-$7,000	$1,500-$5,500
Monthly running cost	$50-$150	$0-$10	$200-$500 natural gas; $250-$1,000 propane
Lifespan	More than 10 years	15-20 years	At least 5 years
Heats quickly?	Slower than gas	Slowly, and only in sun	Fastest
Weak spot	Loses output on cold nights	Cloudy stretches, roof space	Fuel cost

All figures are Fixr’s national numbers, updated January 2025. Its running costs assume a 4- to 12-month season. Florida’s electric and gas rates will move them up or down. Fixr also lists electric resistance heaters at $1,000-$6,000 installed but $175-$600 a month to run. They’re cheap to buy, but they make sense mainly for a small spa.

Heat pumps

A heat pump works like an air conditioner in reverse. It pulls heat out of the outdoor air and moves it into the pool water. Fixr calls it more efficient than electric resistance heating but slower than gas, and says it may be less effective in very cold climates.

Cost by size (installed, Fixr):

• 70,000-85,000 BTU, pools of about 280-450 sq ft: $2,500-$4,000
• 110,000-117,000 BTU, about 450-650 sq ft: $3,500-$5,000
• 137,000-141,000 BTU, about 650-800 sq ft: $4,000-$6,500

Because a heat pump needs warm air to work, its output drops on the coldest nights, exactly when the pool loses the most heat. Some units handle this better than others. Pentair, for example, says its UltraTemp line has an automatic defrost feature that lets it keep running at lower temperatures. It also uses a titanium heat exchanger, which Pentair says gives corrosion-free performance. Ask for the minimum operating air temperature of any model you’re quoted, especially in North Florida. Fixr also notes heat pumps need a dedicated electrical circuit. If your panel is full, the electrical work adds to the price.

Solar collectors

Solar pool heating pumps pool water through panels, usually on the roof, where the sun warms it before it returns to the pool. Fixr prices systems by the number of 4x10-foot panels:

• 4 panels for about 290-450 sq ft of pool: $2,500-$3,250
• 6 panels, about 450-515 sq ft: $3,000-$4,750
• 8 panels, about 515-650 sq ft: $4,500-$6,500
• 10 panels, about 650-800 sq ft: $5,500-$7,000

Running costs are close to zero, since the pool pump does the work, and Fixr gives solar the longest life at 15 to 20 years. The trade-off is control. Solar heats slowly, needs plenty of direct sun, and can’t raise the temperature after a run of cloudy, cold days. FSEC’s guide to solar collector sizing for Florida estimates how much panel area a pool needs to reach those comfort temperatures in average weather. More panel area, or a backup heater, closes the gap in a cold January.

HOAs can’t ban solar collectors

Florida law is on your side here. Under s. 163.04, Florida Statutes, deed restrictions, covenants and HOA declarations may not prohibit solar collectors, or have the effect of prohibiting them, on the buildings in a community. The association may decide where on the roof they go, but only within an orientation to the south or within 45 degrees east or west of due south, and only if that location doesn’t impair the collectors’ performance. The statute also awards attorney’s fees to the prevailing party in a dispute. You’ll probably still need to file an architectural request, but the board can’t simply say no.

Gas heaters

A gas heater burns natural gas or propane and heats water faster than the other options. Fixr says it has the highest operating costs, and that natural gas burns cleaner than propane. Installed prices by size:

• 100,000-150,000 BTU, about 290-395 sq ft: $1,500-$3,000
• 200,000-250,000 BTU, about 450-515 sq ft: $2,000-$4,000
• 300,000-400,000 BTU, about 650-850 sq ft: $3,000-$5,500

Gas makes the most sense if your street already has natural gas service and you heat only for weekends, holidays or a spa. Heating a whole pool with propane for months is the most expensive way to run any of these systems. Fixr’s propane range runs up to $1,000 a month. Running a new gas line or setting a propane tank adds to the job, so get that priced separately.

Combining systems

The options aren’t mutually exclusive. Solar panels can do most of the work on sunny days, with a heat pump or gas heater covering cold, gray weeks or warming an attached spa quickly. Budget for both installations, and make sure the controller decides which one runs first.

For a small pool or spool, heating is much cheaper. Bob Vila prices heater installation for a plunge pool at $1,600-$3,600. See small backyard pool ideas if you’re still choosing a size, and pool cost by city for the pool itself, which doesn’t include a heater.

What to ask your installer about a pool heater

1. How did you size this heater for my pool’s surface area, and what water temperature can it hold on a 45°F night?
2. For a heat pump: what is the minimum operating air temperature, does it have a defrost mode, and is the heat exchanger titanium?
3. Do I need a new dedicated circuit or a panel upgrade? Is that in the price?
4. For solar: how many square feet of collectors, which roof faces, and who handles the roof penetrations and the roof warranty?
5. For gas: is there natural gas at my street, or will this run on propane? What does the gas line or tank cost?
6. Does the permit, the electrical or gas inspection and startup come with the quote?
7. What warranty covers the compressor, heat exchanger or panels, and who services it locally?
8. What is your Florida license number? Look it up yourself at myfloridalicense.com and ask for a current certificate of insurance.

See it in your own yard first

Solar panels on the roof and a heat pump beside the house change how the back of your home looks. An AI concept on a photo of your own house helps you decide where panels and equipment can go before you ask local pros for quotes.