Gas Pool Heater vs Electric Pool Heat Pump (Explained)



No matter how nice your pool is, no one likes swimming in cold water. 

If you live in a climate where it’s not warm 365 days a year, this can be an even bigger problem to deal with.

But you can deal with it… by installing a heater.

There are two popular types of heaters available for pools, so let’s explore the pros and cons between a gas pool heater vs a heat pump.

What Is A Gas Pool Heater?

A gas pool heater operates using natural gas or propane. This means you’ll either need a gas line, or you’ll need to install a propane tank in your backyard. 

The tank required for heating a pool is considerably larger than your standard 4.5 gallon BBQ tank. Pool propane tanks are in the 120 gallon range, so you’ll have to make sure you not only have room for it on your property, but that you can transport it for refills, as it weighs hundreds of pounds when full.

Once hooked up, fire is created inside the heater. The fire heats a copper element which the water passes over. This heats the water quickly, and returns it to the pool at a warm temperature.

Benefits Of Gas Pool Heaters

Installing a gas pool heater has its pros:

  • Fast heating. A gas heater can quickly heat your pool between 1 and 3 degrees per hour. This means you can turn on the heater a few hours before hopping into a warm pool.
  • Heats in cold temperatures. Gas has a low freezing point, making it an exceptional choice to use in cooler climates. In fact, some pool owners will use a gas heater to keep their pool open year-round!
  • Affordable upfront cost. The price of a gas heater is between $1,600 and $3,000 uninstalled. While this seems like a big chunk of change, it’s still cheaper than other heating options.

Drawbacks Of Gas Pool Heaters

Using a gas heater does have some drawbacks though:

  • Requires gas. Either a gas line or a propane tank will have to be installed to run this type of heater. Depending on your situation, this may be a non-issue or a dealbreaker.
  • Expensive operational costs. While gas heaters heat quickly, they’re also expensive to operate due to the amount of gas needed. Depending on usage, expect to pay between $3,600 and $6,000 annually when using a gas heater.
  • Can’t use Indoors. As gas can be quite dangerous, you need to ensure the heater is well-ventilated, and positioning it outdoors is a must.
  • Increased maintenance costs. If any problems arise with this heater, it can be expensive to fix as it contains various moving parts.
  • Not eco-friendly. While it works well, using gas to heat your pool isn’t a very environmentally-conscious option.

What Is An Electric Pool Heat Pump?

A heat pump (an electric pool heater) doesn’t generate heat. Instead, it uses electricity to capture heat from the outside environment, and transfers it into the water. 

The unit does this by sucking in ambient air over an evaporator coil that contains liquid refrigerant. The refrigerant absorbs the heat from the air, turning it into a gas.

The gas is then passed through a compressor which increases the heat, before going through a condenser which transfers the heat into the water that’s running through the unit.

At this point, the warm water gets sent to the pool (thanks to the pool pump), and the hot gas turns back into liquid, returning to the evaporator coil so the process can repeat itself.

Benefits Of Electric Pool Heat Pumps

Like its gas counterpart, an electric heat pump has plenty of upsides:

  • Long lasting. While there are many moving parts inside the unit (ie. fan, compressor, condenser, etc.), as long as you keep up regular maintenance it should last at least 10 years. 
  • Easy installation. Heat pumps are relatively easy to install but should still be done by a professional, as they require the proper electrical hookup to run it.
  • Safe to use Indoors. Unlike gas heaters, heat pumps are much safer to use indoors. Mind you, they can also be very big units, so finding space inside a pump room isn’t always easy.
  • Energy efficient. For those that prefer eco-conscious products, using a heat pump will be the choice for you. Annually, you can expect to pay between $1,200 and $2,400 in operational costs.

Drawbacks Of Electric Pool Heat Pumps

The cons of choosing a heat pump?

  • Slow heating. Heat pumps can only heat 3 to 5 degrees per day. This makes them considerably slower than a gas heater, and they’re also at the mercy of the temperature outside.
  • More expensive. The upfront cost of this unit is between $2,500 and $5,000. Additionally, running it for longer periods of time will mean your electricity bill will increase.
  • Requires minimum outdoor temperature. Heat pumps require an outdoor average temperature of around 50°F. Anything lower and the air being taken in by the pump likely won’t be warm enough to heat the pool water.
  • Heat will top out. Compared to a gas heater (which can make water very warm), a heat pump won’t be able to match the high heat output.

Pool Heater Vs Heat Pump: Which Is Best?

A gas heater is the choice of many pool owners for the fact that it’s quick and can heat to a higher temperature than a heat pump. If you live in a climate with cooler months and you still want to use your pool, a gas heater is the way to go.

Heat pumps do a good job warming the water, but they’re slower, more expensive, and require warm climates to produce warm water – and even then the water temperature won’t get as high compared to a gas heater.

With that being said, if you are fortunate enough to live in a warm climate year-round, a heat pump is certainly not a bad option long-term, it just requires a bit more compromise.

Of course, some choose to include both heaters in their pool system. This is done by heating the pool with the gas heater, and then using the heat pump to maintain that level of warmth.

Don’t Forget About Solar Covers

Adding a solar cover to your swimming pool is highly recommended to alleviate demand on the heater and retain as much heat as possible, without adding any more operating costs to running your pool.

Without a cover, above ground pools lose heat quickly as they have zero insulation. Inground pools do a slightly better job at retaining heat levels due to the dirt that surrounds their exterior, which acts as an insulator. Even then, a solar cover will keep more heat locked in no matter the pool type.

A traditional solar cover looks like a big bubble wrap blanket and acts like a lid does on a cup of coffee. Heat escapes through evaporation on the surface of the water, so keeping a cover on it can significantly suppress heat loss.

Two other types of solar covers are solar rings, and liquid solar cover.

Rings are interlocking inflatables that can be added one by one, instead of wrestling with a bulky solar blanket. Liquid solar cover is an invisible molecular blanket made of high-fat alcohol that floats on the surface of your pool.

Choose Carefully!

When comparing swimming pool heaters, and especially an electric pool heater vs a heat pump, each essentially do the same thing, but also have their pros and cons.

It’s important to take the time to understand these differences, and choose a pool heating solution that works for you.

Categories: Pool Care, Pool Equipment