Heat Pump vs Central AC

A heat pump is one outdoor unit that handles both cooling and heating. It uses a reversing valve to flip the refrigerant flow, so the same compressor and coils that pull heat out of your house in July push heat into your house in January. A central AC is a cooling-only machine. To heat the house, you pair it with electric resistance heat strips inside the air handler, or with a gas furnace. Most Tampa Bay homes go with the heat strip combo because natural gas service is spotty and propane gets expensive fast.

Efficiency ratings tell different stories for each system. Cooling efficiency is rated in SEER2 for both. Goodman GLZS heat pumps run 14.3 to 16 SEER2 in the value tier. Daikin Fit heat pumps hit 18 to 19.3 SEER2. Heating efficiency on a heat pump uses HSPF2, where 7.5 to 8.5 is typical. Heat strips have no HSPF rating because they convert electricity to heat at a flat 1 to 1 ratio, which is the worst-case efficiency in any HVAC system.

The operating cost gap shows up fast in Florida winters. Heat pumps run at a Coefficient of Performance (COP) between 3.0 and 4.0 in our climate, meaning every kilowatt of electricity moves three to four kilowatts of heat into the house. Heat strips run at COP 1.0. In therm-equivalent costs at TECO residential rates, a heat pump heats for around $0.35 per therm of delivered heat. Heat strips cost about $1.20 per therm of delivered heat. That ratio holds steady down to about 35 degrees outdoor air, which covers 99 percent of Tampa winter nights.

The refrigerant cycle is identical in both systems during cooling. The difference is mechanical. A heat pump has the reversing valve, a defrost board, and a slightly larger outdoor coil to handle reverse mode. The compressor itself works harder in heating mode at low ambient temps, which is why heat pumps wear out a year or two faster than AC-only condensers in coastal zones. Both systems use R-454B refrigerant for new installs starting January 2026.

For Tampa Bay homeowners, the heat pump wins on operating cost almost every time. Tampa runs about 2,800 cooling hours per year and roughly 30 to 40 nights below 50 degrees, with a handful of nights below 40. On those cold nights, a heat strip system pulls 10kW of resistance load while a heat pump moves the same heat at 3kW of compressor draw. Over a typical Tampa winter, the operating cost difference between a heat pump and an AC-with-heat-strip combo runs $300 to $600 per year on the same square footage.

A gas furnace makes even less sense at our heating load. Adding a natural gas line to a Tampa home that does not already have service runs $2,500 to $5,000 from the meter. The furnace itself adds $2,000 to $4,000 over the heat strip kit. With our mild winters, the operating cost savings from gas vs heat pump are tiny, maybe $50 to $150 per year. Payback on a gas conversion takes 25 years or more, longer than the equipment lasts. Gas furnaces fit Atlanta and Memphis. They do not fit Tampa.

Coastal corrosion is the one knock against heat pumps in our market. Pinellas and coastal Hillsborough homes within two miles of the Gulf or Bay see salt air eat aluminum coils faster. A heat pump that lasts 12 to 15 years inland often runs 10 to 12 years coastal. That said, a coastal AC condenser also corrodes at the same rate, so the heat pump is still the better economic pick. Coastal-grade coil coatings and annual coil rinses extend life on either system.

For inland Tampa, Brandon, Riverview, Wesley Chapel, and Lutz homes, a heat pump is the right call almost every time. For St. Pete Beach, Apollo Beach, and Davis Islands homes, a heat pump still wins on operating cost, just plan for replacement at year 11 or 12 instead of year 14.