How To Heat Your Swimming Pool

No matter where you travel, when you travel, or how long you’re gone…odds are you’ve wished (or scouted) for a location with a swimming pool. At resorts, hotels, Airbnbs or anywhere in between, lots of people use the swimming pool – which makes it important to know how to heat a swimming pool.
In commercial settings, this is fairly commonplace and part of the protocols for maintenance and upkeep of swimming pools. But what if you own a swimming pool at home? What if you aren’t sure about the ins and outs of swimming pool heating, what you need and how to do it the right way?
Once again, we’re here to answer your questions and provide guidance that will help you maintain and heat your pool properly. Anyone can Google something and find an answer, right? But that’s not always the best course of action – the best course of action is to get your information straight from the pros. Our team at Best in Backyards is well-versed in swimming pool design, construction and maintenance, with decades of experience in all facets.
Whether you have an outdoor swimming pool (which is most common) or an indoor swimming pool, we’ve got you covered. In this blog, we’re going to talk about the various ways and methodologies to heating a pool, and hopefully find which is right for you.
How to heat an outdoor swimming pool
In the warmer months, “how to heat a swimming pool” isn’t always at the top of your to-do list as a pool owner. The sun does a lot of the work for us, and when it’s hot outside, we prefer the water to be a respite from that big glowing orb in the sky.
But there are times when swimming pool heating becomes a necessity – and you don’t want to be caught off-guard when the time comes. Preparation and planning are key to any aspect involving your swimming pool, whether it’s maintenance, water testing, opening/closing for the season, and so on.
Boiler system
A commercial boiler system is among the most common mechanisms used to heat a swimming pool. Using natural or propane gas, these heaters can be placed indoors or outdoors and work with a water pump to heat the water in your swimming pool.
In a nutshell, here’s how the whole system works: once cold water fills your swimming pool, that same water is pumped back out of the pool into a filter, which then passes the water into the heater (boiler). The heated chamber of the boiler warms the water, and the water is then sent back into the swimming pool. This is a continuous flow of water that keeps going until the water reaches a desired temperature.
Pros
Commercial boilers are widely used and available, and if your local swimming pool store doesn’t have them in stock, they likely have dealers or connections that can get you one in short order. Plus, most pool providers are familiar with boilers and can provide maintenance without having to bring in a special or outside contractor.
Cons
Well, in short, it’s a lot of water and a lot of gas. Depending on the size of your swimming pool and how much it’s used (which in turn determines how much it needs to be heated), you’ll see that reflected in your monthly bills. We’ll put it this way: swimming pool heating is not a necessity but it’s something many people want, so you should be prepared to see your costs adjusted accordingly.
Solar power
If saving money and helping the environment is more your thing, then a solar swimming pool heating system is right up your alley. We probably had your attention with “saving money,” didn’t we? Being climate-conscious is equally as important and considering the amount of water used in a swimming pool, we could stand to do a little more to help the planet.
And this is also how to heat a swimming pool fast.
That’s why solar swimming pool heaters are becoming more popular – with both commercial pools (hotels, community pools) and private pools. If you’re also looking to cut your own pool maintenance time down, this is one way to do it. You might be surprised how easy it is to use solar power to heat your swimming pool. The sun might have it out for our skin in the summer months, but we can turn that around and use the sun to our advantage, too.
Pros
Obviously, it almost goes without saying that being environmentally-conscious is a benefit to using a solar power swimming pool heater. These systems include a solar collector (the device through which pool water is circulated to be heated by the sun), a filter, a pump, and a flow control valve.
Here’s what the U.S. Department of Energy says about solar powered pool heating:
Pool water is pumped through the filter and then through the solar collector(s), where it is heated before it is returned to the pool. In hot climates, the collector(s) can also be used to cool the pool during peak summer months by circulating the water through the collector(s) at night.
Cons
Solar power swimming pool heating systems can cost between $2,500 to $4,000, meaning they are an investment – but many studies show that investment will pay off for years down the road. There aren’t many “cons” to this system, but you will need to make sure your pool site has enough solar resources, i.e. unobstructed access to the sun, in order to make this work. Long story short: efficiency of your solar pool heating system depends on how much of the sun’s energy reaches your pool site.
Heat pump
Another commonly-used method to heat a swimming pool is a heat pump. You may have heard of heat pumps, which come in various sizes and structures to fit the dimensions you have in place. A pool heat pump doesn’t actually generate heat (fun fact); it uses electricity and, with a fan built-in, brings in outside air that’s been heated by the sun. Got all that? There’s a quiz at the end.
Just kidding.
The pool pump then circulates water drawn in from the pool itself, going through the filter before it’s distributed back into the pool from the heater. If you have impatient kids or house guests (we’ve all been there), this is how you heat a swimming pool fast.
Pros
Heat pumps do a great job heating the water quickly and are easy to maintain water temperature when the pool is in use. Swimming pool heat pumps use systems that are already in place (electricity, water, etc) and don’t require much adjustment at your pool site other than installation.
Cons
The most common mistake pool owners make is running the heat pump for too long, which isn’t good for both energy efficiency and cost. When the pool is in use, it’s important to keep the temperature where you’d like (usually 75-80 degrees Fahrenheit) and then turn the heat pump off when the pool is not in use.
Swimming pool cover
Not feeling a system, a pump, or something that requires regular maintenance and upkeep? Alright, just for you, we’ve saved the best for last. Thanks to science and innovation, we’ve seen the rise of solar pool covers – and in our experience, customers absolutely love them.
Solar covers are the least expensive and most effective way to heat a swimming pool. If you opened this blog wondering how to heat a swimming pool and saw pumps, filters, circulation, etc., you’ll be glad you read all the way through to learn about a solar cover. Typically, solar swimming pool covers will range from $0.35-0.50 per square foot, so your total cost will depend on the size of your pool.
Pros
You’re saving money and reducing the hands-on maintenance required from the other systems outlined in this blog. Can’t beat that, can you? Covers also prevent heat from escaping your pool, they convert solar radiation into usable heat for the pool, and help with energy conservation by not limiting your pool’s chemical depletion.
Cons
You’re going to need a system to roll and unroll the cover. Manual systems are less expensive, with many hovering in the $300-500 range. If you’re looking for an automatic system, they can exceed $1,000 depending on how large your pool is and how sophisticated you want to get.
How to heat an indoor swimming pool
There’s really one primary method used to heat indoor pools – and that’s a heat exchanger.
What’s a heat exchanger, you might ask? It’s a system that uses hot water either from a boiler or solar-powered source to heat the water in your swimming pool. Basically, the heat exchanger passes heat from one fluid (the boiler water) to another (your pool water), and they’re quite common in commercial pools, hot tubs, hot water supplies etc.
If this is the route you choose, look for brands that offer corrosion-resistant materials. This ensures your heat exchanger will last for a long time and save some of the costs. Fair warning, heat exchangers can be expensive.
How much does it cost to heat my swimming pool?
This is one of the most common questions we receive. The short answer is “well, it depends” and the longer answer is “it depends on several factors, including where you live, how often you use your pool, and more.”
A quick sweep of information provided by pool heating companies and suppliers gives us this: the average (key word: average) cost to heat your swimming pool throughout the swim season (May through early September) is between $2,000 and $4,000. Remember what we talked about above? Paying attention to when your pool is in use, requiring water heating, and when it’s not used will have a significant impact on your total cost.
How long does it take to heat a swimming pool?
Here we go again with “it depends,” but it’s true.
The pool heating system you’ve selected will determine how long it takes to get your swimming pool’s water to the desired temperature. Heat pumps and solar covers have demonstrated to be the most efficient in terms of time; for example, most pools in mild climates can see their water temperatures rise by 15-20 degrees in as little as 24 hours, and as much as 72 hours.
There’s no quiz at the end, but there is a lot of information to take in.
Hopefully you’ve learned enough in this blog to make an informed decision about how you’ll heat your swimming pool. Want to figure out how to heat a swimming pool fast? Look at a heat pump or a solar pool cover. Swimming pool heating is not an exact science, but more determined by what you have in terms of site, resources and footprint, and also how much energy and money you prefer to spend.