The days are getting shorter and the leaves are starting to change. Pool season is coming to an end… or is it? Who says you can’t swim when the weather gets chilly? 

Whether you want to extend your swimming season for months or just hate jumping into a chilly pool for your morning swims, a pool heater may be just what you need.  

Swimming pool heaters are an excellent addition to a backyard pool that can increase your swimming season and your family’s enjoyment of your pool for years to come.

Top Picks for Best Pool Heater

Preview Product Price
Hayward H400FDN Universal H-Series 400,000 BTU... Hayward H400FDN Universal H-Series 400,000 BTU... $3,199.00
Hayward HP21404T HeatPro Titanium 140,000 BTU Heat... Hayward HP21404T HeatPro Titanium 140,000 BTU Heat... $3,999.99
SmartPool S240U Universal Sun Heater, 4 by 20-Feet SmartPool S240U Universal Sun Heater, 4 by 20-Feet $198.58
EcoSmart SMART POOL 27 Electric Tankless Pool... EcoSmart SMART POOL 27 Electric Tankless Pool... $902.63
Smartpool S601P SunHeater Solar Heating System for... Smartpool S601P SunHeater Solar Heating System for... $198.99

What is a Pool Heater?

A pool heater is an accessory for your pool that you can get to regulate the temperature of your pool and extend your swimming season if you live in a cold climate. Just like the water heater in your house that warms your shower and bath water, a pool heater warms the water in your pool to take the edge off on a chilly morning or allow you to swim for a few extra months.

Regular home water heaters are completely different beasts from pool heaters and the two are definitely not interchangeable. To warm the water in your swimming pool, you need a special appliance for the job.

Pool heaters come in all shapes and sizes with different capabilities and strengths. There are a lot of options out there and finding the right one can seem a bit overwhelming. Your type of pool, personal preferences, the area you live, and your budget will help you to pick the best heater for your pool.

Why You Need a Pool Heater

If you live in a colder climate and want to extend your swimming season by a few weeks or months, a pool heater is practically a necessity. Even if you live in a warmer area and just want to take the chill out of the water before your morning swim, a pool heater can be your best friend.

Your pool is a great asset that adds value to your home and your quality of life. But if you only get to use it 2-3 months out of the year, you’re missing out on weeks of fun that you otherwise might have enjoyed.

Do you suffer from sore muscles or painful joints? Warm water has been shown to be extremely therapeutic for these conditions and can relax stiff muscles while you’re swimming around in your pool. As you can see, there are many great reasons to invest in a pool heater to increase the value of your swimming pool and your enjoyment of it. 

Finding the right pool heater, however, can be a bit tricky. Getting a super-powerful heater might end up costing you a fortune in utilities, whereas getting a small heater might not do the trick if you have a larger pool. The good news is that we’re here to guide you through the process of finding you the perfect pool heater for your needs and budget.

What Types of Pool Heaters Can You Buy?

Gas

The good news is that you have a lot of options when it comes to purchasing the perfect pool heater for your pool. The most common types of heater are gas-powered and those come in three different versions too. 

  1. Coil Gas Pool Heater

This type, which is also the most common among gas heaters, runs your pool water through a coil that is heated by several open flames. The water moving through the coil is heated as it circulates. These heaters are best for larger pools because of their speed and efficiency.

  1. Convection Gas Pool Heater

Convection heaters work by means of a single large flame that gradually raises the air temperature inside the device that the water is moving through. This type is best for smaller pools and spas since they work more slowly than other options.

  1. Tank Pool Heater

Tank heaters are the most like your home’s water heater. These work by warming up the water in the tank and then letting it out when you’re ready to swim. The only downside to this type is that once the water in the tank runs out, you have to reheat another tank.

Gas-powered pool heaters are generally inexpensive to operate, require little maintenance, and don’t have too many moving parts. If you happen to live in a place where natural gas is cheap, then lucky you! A gas pool heater won’t raise your utility bill too much and might be the best option for you.

A Note About Gas Heaters: Gas pool heaters generate emissions that are harmful to the environment. Some US states now require gas heaters to be certified “low NOx”. This means that they produce lower amounts of the chemical, nitrogen oxide. It’s a good idea to get a low NOx model anyway, but even more so if your state requires it by law.

Electric

There are two main types of electric pool heaters and although they sound similar, they couldn’t be more different. 

  1. Electric Pool Heat Pump

Electric heat pumps take in warm surrounding air and use compressors to pressurize it, which increases the temperature. The heated air is then transferred to the pool water, which warms it up. These are a very efficient and eco-friendly way to warm up even large swimming pools. 

Powered only by your electrical connection, heat pumps are generally more expensive upfront than other types of pool heaters, but won’t cost you much in utilities over time. With a heat pump, your monthly costs can be as low as five times less than with gas or electric pool heaters.

They have a lot more moving parts than gas heaters, so there is the potential for components to break or malfunction. However, a well-made heat pump should last just as long as a gas-powered pool heater.

Heat pumps are ideal for pool owners that live somewhere that never gets below 40 degrees since they function more efficiently when there is some warmth in the outside air. Overall, heat pumps work very well, last a long time, and can even heat a pool when it’s under 50 degrees outside.

  1. Electric Pool Heater

You can think of an electric pool heater as a little space heater for your pool. It has a metal element inside that heats up and warms the water as it is circulated through. These kinds of heaters are generally cheaper than other types but are not as efficient and take a while to warm all of the water in a really big pool.

They also use a lot of electricity to get the job done, so you’re going to notice a jump in your electric bill when you use it. Electric pool heaters are typically ideal for spa owners since there is less water to heat. However, if you’re not worried about your utility bill and you want warm water fast, these can be a good option.

Solar

There are actually two different types of solar heaters. The first is the simplest, a solar blanket (a thin, plastic sheet) that you lay across the surface of your pool. These help to increase the amount of solar energy absorbed by the water in your pool and keep heat from escaping. They are very inexpensive but also the least efficient. Using a solar blanket paired with a solar heating system, however, will keep the water you’ve already heated warm for longer.

The second option is a solar system. No, not that solar system. A solar heater system. This type may remind you of the solar panels that you can put on your roof. Solar pool heaters, however, are not powered by the sun, they actually just feed water into the panel and let the sun heat the water naturally.

Solar pool heaters are a great option because once you purchase and install the unit, you’re all set. The sun is heating your pool water and all you need to do is let it work for a warm, toasty pool. Solar heaters do come with a higher price tag initially, but since they have no utility costs and hardly any maintenance costs, they will save you money over time.

Solar heater systems require a lot of space and are usually installed on your roof so as not to monopolize your entire backyard. This actually protects your solar heater from damage on the ground and allows it to do its job more efficiently, especially if you have asphalt shingles which radiate heat from the sun back onto the water into the solar heater.

The main drawbacks to solar heater systems are (1) Dependency on the sun (i.e. they won’t work on a cloudy day) and (2) It takes a while to warm the water up, compared to gas or electric heaters. Solar heaters, however, are the most eco-friendly option on the list and work best for pool owners that live in sunny places.

Pool Heater Pro Tip: To get the most out of any pool heater, make sure that the water in your pool is clean and properly balanced at all times. If your chemistry needs a bit of work, turn off the heater until everything is back in order.

Which Type is Best?

The best pool heater is going to be different for every pool owner and will depend on several factors, as well as personal preference. The climate in which you live, your budget, the size of your pool, as well as how much you plan to use the heater are all going to affect which pool heater is best for you. 

What to Consider When Buying a Pool Heater

In order to find the perfect pool heater for your pool and lifestyle, there are a few things you should consider before making a purchase. Pool heaters are a big investment that will last you for years to come so make sure to consider your needs and options carefully before making a purchase.

What size pool do you have?

The size and capacity of your pool is a good place to start when deciding on a new pool heater. The larger the pool you have, the stronger the heater you’ll need to make a difference in the water temperature. Whereas a powerful gas heater might be great for a big pool, a solar heater might be perfect for a smaller pool.

This same idea applies to finding the perfect heater for an in-ground pool versus an above-ground pool as well. A robust electric heater may end up being a huge waste of money for an above-ground pool and a solar system might not do the trick with a 40,000-gallon in-ground pool.

Price: What is your budget?

When purchasing a new pool heater there are several price factors to consider. Of course, there is the upfront cost of the appliance itself but then there is also the monthly cost of utilities to take into account. Here’s how the different types of pool heater stack-up on a monthly cost basis:

Gas: The upfront cost of gas pool heaters varies between brands and the power of the machine. These heaters will heat your pool the fastest but they will burn a lot of gas in the process. 

Depending on the cost of natural gas in your area, your utility bill might suffer. On the other hand, the monthly cost of running a gas heater will probably always be cheaper than an electric pool heater.

Electric: Electric pool heaters with heating elements are the most expensive option when it comes to your monthly utility bill. Operating these bad boys will cost you more than $50 per month… ouch. 

Electric heat pumps, however, are a very cost-effective option that will only cost you a fraction of that. With no heating element inside, you’re only having to power the compressor, making these a more affordable option in the long run.

Solar: Solar heater systems are one of the least expensive options in terms of upfront costs. They will also cost you nothing in utility bills, which makes them the most affordable option out there. Unfortunately, they’re the least effective heating option and require the weather’s constant cooperation to properly do their job.

Performance: How fast do you need it to heat up?

If you’re looking for a pool heater that will get your pool nice and toasty warm in just a few hours, then a high-performance electric heater is probably your best bet. If you’re willing to wait and want to save money on your monthly utilities, a gas or solar-powered heater might be the perfect fit.

Installation

Pool heaters are probably one of the most costly pieces of equipment you’ll ever buy for your pool. For that reason, it’s a very good idea to invest in professional installation of your new heater, regardless of how easy it looks to install. 

Be sure to take this added expense into account when budgeting for your new pool heater. It will save you tons of time and frustration in the long run!

Best Pool Heater Reviews

#1 Hayward H400FDN Universal Natural Gas Pool Heater

Hayward H400FDN Universal H-Series 400,000 BTU...
Hayward H400FDN Universal H-Series 400,000 BTU...

    DESCRIPTION

    gas heater with 400,000 BTUs, this is an extremely powerful unit and can heat up a 20000 to 40000-gallon pool very fast. Called “universal” because the gas, water, and electrical connections can be run on either side of the heater

    Pros:

    • Very easy to use and program
    • Environmentally-responsible low NOx emissions
    • Fast heating and very efficient

    Cons:

    • Can be quite noisy
    • Keyboard requires on-going maintenance

    #2 Hayward HeatPro HP21404T Titanium Electric Heat Pump

    Hayward HP21404T HeatPro Titanium 140,000 BTU Heat...
    Hayward HP21404T HeatPro Titanium 140,000 BTU Heat...

      The Hayward HeatPro Titanium Heat Pump uses titanium counter-flow heat exchangers for unrivaled performance – even under the harshest conditions. The evaporator fin is made from corrosion-resistant materials with waterline connectors made of stainless steel for durable, efficient, and most importantly, quiet operation. Best for smaller pools and spas.

      Pros:

      • Extremely durable titanium heat exchanger
      • Very quiet due to sound dampening technology 

      Cons:

      • Shell is made of less-durable plastic
      • Make sure to get professional installation to maintain warranty compliance

      #3 SmartPool S240U Universal Sun Heater

      SmartPool S240U Universal Sun Heater, 4 by 20-Feet
      SmartPool S240U Universal Sun Heater, 4 by 20-Feet

        The SmartPool Universal Sun Heater is the most cost-effective way to warm your pool. Capture free heat from the sun’s rays to raise your water temperature 6-10 degrees F. This product can add weeks to your pool season. The universal system is suitable for both in-ground or above-ground pools and works best in mild, sunny climates.

        Pros:

        • Excellent value for the price
        • No monthly cost
        • Environmentally-friendly
        • Quick and easy installation

        Cons:

        • Not ideal for larger pools
        • Weather-dependent

        #4  EcoSmart Electric Tankless Pool Heater

        EcoSmart SMART POOL 27 Electric Tankless Pool...
        EcoSmart SMART POOL 27 Electric Tankless Pool...

          This electric tankless pool heater by EcoSmart operates by utilizing the latest flow sensor technology instead of the traditional pressure switch activation to reduce the risk of burned elements, which increases its reliability and longevity. Its small footprint, super-fast heating capability, digital thermostat, and low price make this pool heater a superb value. For best results, get professional installation.

          Pros:

          • Tankless and super compact
          • Comes with a 2-year warranty
          • Very quiet operation
          • Also works well to boost an existing heater

          Cons:

          • Needs professional installation
          • May require additional circuit breakers
          • May significantly increase electricity costs

          #5 Pentair 460805 MasterTemp Eco Natural Gas Pool Heater

          The Pentair MasterTemp Pool Heater offers efficiency, convenience, and reliability, plus fast heat-up, compact design, super quiet operation and easy to use controls. The 400 BTU model can heat a 40k gallon pool up to 6 degrees in 6 hours. With a rust-proof exterior and rotating digital display, this compact and quiet heater is great for spas or any pool size. 

          Pros:

          • Super energy-efficient
          • Can quickly heat very large pools
          • Intuitive digital controls
          • Low NOx emissions

          Cons:

          • Can significantly increase utility expenses
          • May be missing pieces on delivery. Make sure to buy from a trusted seller.

          #6 Smartpool S601P SunHeater Solar Heating System for In-Ground Pools

          Smartpool S601P SunHeater Solar Heating System for...
          Smartpool S601P SunHeater Solar Heating System for...

            The high-density solar heater from Smartpool uses sunlight to heat the water and has a very low operating cost versus standard heaters. Water runs through a thin plastic bag that can be roof-mounted. Keep your pool warm this winter with a polypropylene heat collector and 80 square feet of solar panels.

            Pros:

            • Inexpensive to operate
            • Eco-friendly
            • Consistently heats the pool by 3-7 degrees on a sunny day

            Cons:

            • Requires a powerful pump to get the water to the roof
            • Weather-dependent
            • No instructions included

            #7 Sta-Rite SR400NA Max-E-Therm Natural Gas Pool & Spa Heater

            The Max-E-Therm heater is perfect for indoor or outdoor pools or spas and features an LED temperature readout with dual thermostat controls, 6-position control panel and PVC union connections. Its high-efficiency rating makes it extremely economical to operate. Certified for low NOx emissions and outperforms industry standards for air pollution exhaust. 

            Pros:

            • Easy to use LED display
            • Low NOx emissions
            • Lightweight, durable, and compact
            • Works super fast

            Cons:

            • Runs a bit loudly
            • Saltwater pools will corrode the heating element

            Conclusion

            With a quality swimming pool heater, you’ll never miss out on months of fun or risk jumping into chilly water again. A pool heater allows you to enjoy your pool longer and helps you to get more value out of your swimming pool. It also makes swimming in your pool a more fun and healthy experience all around.

            A pool heater is an excellent investment in your pool and after a great filter, probably the best pool accessory you can get. There are a variety of options out there for every pool, lifestyle, backyard, and budget — now all you have to do is pick one out!