Pool Heater Types: Gas vs Heat Pump vs Solar
Short answer: Gas heaters heat fastest and work in any weather but cost the most to run. Heat pumps cost far less to run and suit mild to warm climates, and they slow down in cold air. Solar heaters have the lowest running cost but depend on sun and roof or ground space. Check that each quote names the type, model and size of the heater.
The main types
| Gas (natural gas or propane) | Electric heat pump | Solar | |
|---|---|---|---|
| How it heats | Burns fuel to heat the water | Moves heat from the air into the water | Water circulates through roof or ground panels |
| Heating speed | Fastest | Slower, steady | Slowest, weather dependent |
| Running cost | Highest | Much lower than gas | Lowest |
| Cold weather | Works in any temperature | Efficiency drops as air cools, and many units stop in near-freezing air | Needs sun |
| Needs | Gas line or propane tank | Adequate electrical supply | Sunny, unshaded area |
| Best for | Quick heat, spas, cold climates | Extending the season in mild to warm climates | Sunny climates and low running cost |
Heat pump efficiency is rated by coefficient of performance (COP). Manufacturers and trade sources commonly cite COPs of roughly 4 to 7 in warm air, which means about 4 to 7 units of heat delivered per unit of electricity. The figure falls as air temperature drops. Gas heater efficiency is typically cited in the 80s to mid 90s percent. Treat all of these as ballpark numbers and check the spec sheet for the model quoted.
Cost
Upfront prices for the three types overlap, and online ranges conflict. Running cost is where they separate: industry estimates put gas as the most expensive to operate and heat pumps and solar as much cheaper per season. Local gas and electric rates change the answer, so ask your builder for an estimate based on your area.
Lifespan
Sources disagree on exact figures. As a general pattern, heat pumps and solar systems are cited as lasting longer than gas heaters, especially in hard water or heavy use. Ask about the warranty on the unit and heat exchanger.
What to check on a pool quote
- Type, brand and model, not only "heater."
- Size. Gas heaters are sized in BTU. Heat pumps are rated at stated air and water temperatures, so ask what conditions the rating assumes.
- Gas line or electrical. A gas heater may need a gas line run to the pad, and a heat pump needs electrical capacity. These are commonly excluded costs. See the quote checklist.
- Pool cover. A cover reduces heat loss and heater runtime for any type.
- Spa. A spa attached to the pool may call for a different heater than a pool alone.
Frequently asked questions
Is a heat pump or gas heater better for a pool?
A heat pump costs much less to run and suits mild to warm climates. A gas heater heats faster and works in cold weather. Local energy prices and how you use the pool decide which is better.
Do I need a pool heater at all?
Not necessarily. A heater extends the swim season and is almost essential for a spa. If a quote leaves it out, compare quotes on the same basis rather than assuming it is a saving.
Do it automatically
Pool Quote Compare reads two to four proposals from PDF or pasted text, fills in the fields, and shows the quotes side by side with exclusions lined up.
Compare heater and equipment details across your quotes