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The 4 plus one ways for heating the water in your above ground pool

It doesn’t really matter where you live. You don’t have to live up north to want to heat your above ground swimming pool. Even in the hottest climates, if the pool has a canopy of trees hanging over it or it’s screened-in, then the water may stay too cold to enjoy comfortably. And almost everyone would like to extend their swim season.

Here in Central Florida, many inground pools have heating capabilities, but not too many above grounds. THE REASON – Cost!

The four ways to heat an above ground swimming pool are by using a gas heater, heat pump, electric heater, and solar panels. The bonus system is a wood burning heater. They are rare but unique.


Before I get into the different types of pool heaters available, I want to address the biggest issue with heating an above ground pool. And that is it’s expensive. Now, there are the cheap little round solar panels that you can buy made for above grounds. But they are just some black hoses pinned to a board and placed in the sun. They work a little, but not in the way you want them to.

To legitimately heat thousands of gallons of outside water, it’s gonna cost a lot. This isn’t to say that you wouldn’t be willing to pay, but it’s good to know this upfront so you don’t buy a heater and have it installed only to use it once and never again due to “sticker shock” with the gas or electric bill.

So just to be clear, the initial cost of the heater and its ongoing cost to heat the above ground pool will be considerable.

NOTE: Regardless of which way you heat the pool, heating it will require running the pump longer which adds to the expense with more electricity cost.

4 ways to heat your above ground pool


There are only four (plus one) options for heating a swimming pool. Don’t believe in covers or liquids doing the job. There are no short cuts using a shiny cover made out of NASA material or a $12 magic pill that you simply toss in the pool.

If you want to believe in heating magic, please, I invite you to read elsewhere. Here, I’m just going to cover what I know works based on my 35 years of being in the pool business working with calloused hands and wet feet.

HEAT PUMP #1 Option to heat an above ground pool

Above ground pool equipment pvc plumbed with an added heat pump
Heat pump added to pool equipment

Overall, this is probably the best option for most wanting to heat their pool. A heat pump is the most economical method for heating a large body of water.

PRO Most Efficient – In terms of heating ability, the heat pump is most efficient. It will take less energy (electricity) to heat the water, so it will cost you less to heat your swimming pool.

CON Takes longer to heat – Heat pumps are a great option in most ways unless you’re in a hurry to heat the above ground pool up. Heat pumps can take more than twice as long as a comparable electric or gas heater.

In the case of a swimming pool that has thousands of gallons, a heat pump can take a day or two longer than the other heating options.

CON – Stops working when outside temperature is cooler than 42 degrees Fahrenheit (6°C)– This is a big con for those wanting to heat their above ground pools in the winter. At around 40 degrees Fahrenheit, the heat pump loses its ability to pull heat out of the air to a noticeable amount.

I was surprised to see that there is no actual temperature that the industry considers the “cutoff” for when a heat pump no longer works to heat pool water. For me, it was 42 degrees Fahrenheit (6°C). I got this number from observing a few heat pumps on my pool service route in Orlando.

It doesn’t get in the low forties much in Orlando, but when it did, the heat pumps were no longer able to raise the pool water temperature even one degree. So, for me, 42°F (6°C) is the cut-off.

CON The cost of the unit is higher – As mentioned earlier, I think heat pumps are a great option for many. And although the cost to operate is much less than gas or electric, the start-up cost for heat pumps are considerably higher.

CON – Requires a good amount of electricity, and usually in 240V – Even smaller heat pumps will require 30 amps of 240-volt electric run to them. Some take 50-60 amps (yikes).

This can really add to the cost of getting a heat pump, especially when talking about an above-ground swimming pool. The equipment for above grounds usually sit right next to the pool, and usually only requires 120-volt electric.

A heat pump needs a lot of amps of electricity, and it needs it in 240 volts. This means that the electric now being run for normal above-ground equipment will now need to be fancier. So, depending on your situation, you may need to spend as much as a couple thousand more dollars to have an electrician run electric to your pool’s equipment just because you have a heat pump.

PRO – Works when you want it to. Can lie dormant – This is a bigger pro than you might think. Most people only use their pool heaters occasionally. Some will only use it when there’s a party or family is coming from out of town.

Most of the time, a pool heater just sits there not being used. When the time comes to use it, you want it to work. Gas heaters don’t like to sit unused and will act up or need to be serviced if dormant too long.

Heat pumps are very reliable after sitting unused. This is a big plus.

BEST HEAT PUMP APPLICATION: When wanting to keep a pool warm for a long period of time

WORSE HEAT PUMP APPLICATION: When needing an above ground pool to heat up quickly, TRYING TO HEAT THE POOL IN THE WINTER(BELOW 42°F/6°C)


Gas heaters work well and fastest for heating a swimming pool. They are especially nice for houses that have gas.

PRO – Initial cost not as much – Gas heaters aren’t cheap, but they are much less expensive than heat pumps.

PRO – Heats the water fastest – For in-ground hot tubs/spas, gas heaters are the number one choice. This is mainly because of the speed with which it heats up the water. Nothing can heat four hundred gallons of water from 75°F to 105°F faster or more efficiently as gas.

When it comes to a swimming pool though, we are talking about a lot more gallons. So, even though gas heats water fast, it’s still gonna take a while to heat 10k gallons of water. There’s a big difference between 400 gallons and 10k gallons.

CON – It takes a lot of gas to heat an above ground pool. As mentioned above, heating a 400-gallon hot tub doesn’t take much gas to heat up even 30°F higher. But a swimming pool has thousands of gallons of water. And it takes a lot of gas to heat.

What this means to you is it’s gonna cost you a lot in gas to heat a swimming pool, especially if you are trying to heat it more than just a few degrees.


Way back in the nineties when I had my pool service business, I had a few millionaire customers with beautiful houses and pools. The one I’m talking about here were rich people living in this neighborhood near me called Isleworth. (This is the hood where Tiger Woods lived when his ex-wife beat him up with a golf club for cheating).

This wealthy couple just had their house built and I was the one to service their new pool. When winter came, they asked me about heating their pool for some out of town family coming. I told them they had a gas heater and that I would get it going to them.

I told them it wouldn’t be cheap to heat their pool and the gas bill will be high. Being the ballers they were, they dismissed my warning and heated their pool for about four days while the family was staying there, then turned the heater off.

A month later, I got a call from Mrs. rich lady asking if I thought there was something wrong with the pool heater. I told her I didn’t think so and asked why.

“Well, do you remember when we heated the pool last month”?

“Yes”, I replied. “When your family was in town”.

“Yes that’s right”, she said. “Well today I got the gas bill and it was $900 more than it normally is. We only used the heater for four days. Does it sounds right that it costs $900 to heat the pool for 4 days”?

“Wow. That’s a lot, but you have a big pool, so it sounds about right to me” I said. (Keep in mind that this was the 1990s too.)

“Ok if that’s what it cost to use, don’t worry about servicing that heater. We will never use it again”.

“OK, no problem. Yeah, it’s not cheap to heat a pool”, I reminded her and we hung up.

In this example’s defense, these rich people’s pool was about 40k gallons, they had a huge gas heater, and they never covered the pool while it was heating. But it still costs a whole lot of money to heat a pool.

CON – Requires regular usage or it breaks. If a gas heater lies dormant for even a month, it may need servicing to work again. And even if it does work, re-lighting the pilot light can be a royal pain.

You may have an easy time with this, but coming from a guy who has singed some facial hair while lighting gas heaters, I can tell you it may be a pain.

For those on my pool service route who had gas heaters that they actually used on occasion, I would turn it on every time I was there and run it for a few minutes. This would keep the unit operational when the pool owner wanted to use it.

CON – It may be hard to get gas to it or have a tank installed. A gas pool heater needs gas. Duh! This means you’ll have to get a gas source to the unit. For homes with gas, a gas line has to be run to where the heater is, which is somewhere next to the pool.

For those without gas, a tank will have to be leased and installed, then a line has to run from it to the heater unit. This is an extra step and can really add to the job.

PRO – Works no matter how cold it is. As long as the water isn’t frozen and can run through the unit, it can heat the water up. This is a plus for those living in colder areas and want warm(or at least tolerable) water to swim in during the winter. You’ll want to work some overtime though.

BEST GAS HEATER APPLICATION: When needing the water to heat fastest

WORSE GAS HEATER APPLICATION: When needing to maintain warmer water for an extended period


It’s super cool to be able to heat pool water with the sun, but solar heating a swimming pool has pretty severe limitations.

PRO – Doesn’t cost anything to work. This is the only method for heating pool water that costs absolutely nothing to use. Water just pumps through some pipes directly pointing to the sun, and the sun heats the water as it passes through.

CON – Initial setup can be difficult. In order for a solar heater unit to work well, it has to be pointed to as much direct mid-day sun as possible. This can be tricky depending on where the pool is in the yard, how many trees you have, and which way the house is pointed.

There are some inexpensive solar units for above ground pools. They are designed to lay on the ground next to the pump/filter. This may not work well if that area of the yard doesn’t have much direct sun. Plus, they are small, so don’t expect them to change the water temp of the pool by too much.

To have a more legitimate solar pool heating system usually requires running solar panels up on the roof of the house. This is because the panels most often can get more direct sunlight up there than anywhere else in the yard.

Also, the more solar panels you have, the more it can heat the above ground pool, so having enough panels will take up a lot of yard space. Installing them on the roof puts them completely out of the way.

CON – Doesn’t work well in the colder months – When the sun is closer, it’s hotter. In the cooler months, the sun is further away, so it doesn’t heat up the above ground pool water as much as it passes through the solar system.

Even here in Central Florida, solar pool heaters don’t work very well from October to March.

CON – Requires more maintenance, otherwise, there can be leaks – Swimming pool solar heating systems will eventually leak. This is just an unfortunate fact. They will leak a lot less and won’t start leaking for a longer time if you routinely inspect and clean the panels.

BEST SOLAR HEATING APPLICATION: When needing your pool to be just a few degrees warmer during the summer months.

WORSE SOLAR HEATING APPLICATION: When wanting the water heated during the winter.


If sized big enough, an electric swimming pool heater can work well, but you’re gonna pay.

PRO- Initial cost not as much – An electric heating unit is the least expensive heating set-up you can get. (I’m not counting the cheap above ground solar units because they don’t do much)

PRO – Doesn’t take up much space. Electric heating units take up the least amount of space than any other heating option. This is great if you don’t have a lot of space where your pool’s equipment is.

CON – Cost a lot to use in electricity. Electric pool heaters aren’t very efficient, so you’ll be paying a whole lot on your electric bill if you use one. This is the main reason that they aren’t very common.

CON – Requires 240 volt – Big electric demand requires 240 volt, which is two 120 volt hot lines. This is a con because with above-ground pools, the pump and other components that require electricity need only 120 volts.

This means that if you have a big electric heater, it will need special electric (so to speak) and will cost you a lot to have it run.

PRO – Requires the least maintenance – Electric heaters are the easiest of all heating systems to maintain. It’s a shame that they cost so much to use.

BEST APPLICATION: For heating a pool in the winter and there’s no option for gas

WORSE APPLICATION: To heat the pool for an extended period during the winter. The word here is “pricey”.


I am only considering this type of heater as a fun alternative. They aren’t popular enough then to be anything more.

CON – It may be hard to find a good one. No major manufacturers that I know of make wood burning heaters. What this means is that you’ll have to buy one from a guy who builds them. This could be great or it could be bad.

As a swimming pool guy for all of my working life (34 years and counting), I understand that water always creates a harsh environment for everything around it. This means that even if some guys are really good at designing and constructing things well, they can fail when it comes to building something for water.

I’m sure that there’s at least one guy out there in the world who sells a rock-solid wood burning pool heater. However, I have no clue who that is.

CON – It takes constant work to operate. If you love chopping wood and keeping a fire stoked (I know that I do), then operating a wood burning pool heater may be a fun workout for you. For everyone else though that just wants their pool heated, this will be a lot of constant work.

PRO If you have free wood, it costs little or nothing to use. And if you have to pay for wood, the cost will add up probably faster than you think.

PRO – Will work well in any outside temperature. A fire burning heater will in no way be ambient temperature sensitive, so you’ll be able to use it no matter what time of year it is.

BEST APPLICATION: If you have free and easy access to wood and want to heat the pool in the winter.

WORSE APPLICATION: If you only want to heat the pool with the press of a button


It costs a lot to heat a swimming pool one way or another. And once the water is heated, it can escape very quickly out from the surface of the pool. This is why using a solar or insulated pool cover while heating the pool is absolutely imperative!

Keep the cover on the pool while heating and when done heating. If going swimming, take the cover off, and then replace it when you are done.


Dan writes with the knowledge of having 35 years (and counting) in the above ground pool industry.

8 thoughts on “The 4 plus one ways for heating the water in your above ground pool

  1. Just need the best solar blanket with roller to heat pool the best I can.

    What would you suggest for 9×18 rectangular pool.

    The hookups of other ‘types’ frighten me.

    1. I’m not sure if one is any better than the other. Solar covers are not high quality. Using a roller to your liking and convenience will be a trial and error process. There is no one great way to do it. Every situation is unique. Good luck.

  2. Hi I hear all different answers for solar covers that work best. I heard a clear colored is better to let sun in. I also heard no darker color the better could you please tell me what you suggest. Thank you

    1. Solar covers are insulators. That’s all. With that in mind, then how would a different color make a difference? I kinda hate how the industry sells solar covers as heaters. With that, it makes people think that the color would make a difference. And that would make sense if a cover was a heater. But it isn’t.

      So, a different color of solar(insulator) blanket working better is like a different colored wool blanket working better. I have a blue wool blanket and a brown one that I use. They both keep me warm the same, although I like the blue one better. lol.

      Reading this may help give my opinion: https://abovegroundpoolsknowitall.com/do-solar-covers-work-on-above-ground-pools/

  3. I live in Michigan and I’m looking to have a heatpump installed. One company wants to sell me a 125k to 150k BTU Heat Pump. Another says 95k BTU should do the trick.

    I’m looking to swim in early May till October. I have a Hayward 24 ft flat bottom pool.

    What make and model would you recommend? ComfortTemp seems to be the most economical.

    1. Sorry. I’m not able to help with sizing and model options. In the future, I’ll be writing an article about it. I have limited real world exposure to heaters for above grounds as there aren’t many here in Central Florida.

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