thermal solar panels installed on the roof of a large house

10 Best Solar Pool Heaters in [current_year] (Review)

Jumping into a swimming pool is not always a fun experience, especially during the fall and spring season when colder winds start blowing.

Most homeowners will have a gas pool heater to increase the temperature of their pool water. However, constantly paying gas bills that increase due to the extra consumption of gas can be very expensive and undesired. Electric heaters have the same problem with high costs.

The economical and eco-friendly solution is to install one of the best solar pool heaters in 2021 available from multiple brands such as FAFCO, Smartpool, Sun2Solar, Sungrabber and many more. Just as the solar powered showers, these use the sun as a source of heat that can be used to increase the temperature of the water inside in an environmentally friendly way.


Written by qualified solar engineer Carlos. Last updated:

The Best Solar Pool Heaters

1. Fafco Solar Bear Solar Pool Heater

Key Features:

  • Solar heater for above ground pools
  • Mounting racking tilted between 20-45°
  • 10-year warranty

Key Specifications:

  • 80,000 BTUs generated by day
  • Solar collector size: 4 ft. x 20 ft.
  • Additional 7-10 degrees Fahrenheit to the swimming pool

Where To Buy

Fafco is one of the first American companies related to the development of solar water heating systems. The developer of copolymer blend materials and collector panel designs that made it one of the largest distributors of solar pool heating systems in the US.

In this occasion, we are evaluating the solar bear pool heating system of the brand that has been specially designed for above-ground pools. The system consists of a 4 ft. x 20 ft. large solar collector with 1-1/2” barb connections that can be laid down on the ground next to your pool to reduce the size of the hose needed. However, the FAFCO solar system can also be installed on a mounting racking that can have a tilt angle between 20-45° while facing South to optimize heating and maximize efficiency.

This above-ground solar pool heater produces up to 80,000 BTUs of heat per day, which is enough to heat a 24 ft. round pool 7-10 degrees warmer than their ambient temperature value. Besides, the solar pool heater kit also includes an integral bypass valve, mounting base, cap straps, and rubber tube plugs.

This product is easy to install as it only requires about 30 minutes to complete the installation, and it has received a lot of positive solar pool heater reviews.

2. SunHeater S120U Universal Solar Pool Heater


Key Features:

  • Patented web design for maximum exposure to the sun’s rays
  • Uses existing pool pump
  • Simple DIY installation

Key Specifications:

  • Solar heating collector: 2 feet x 20 feet long
  • Increases temperature 6-10°F above
  • Dimensions: 120 x 27.5 x 16 inches

Where To Buy

SunHeater S120U provides an amazing alternative to heating your pool, especially during the spring and autumn seasons.

A solar heater for pools can be designed to fit inground or above ground purposes, however, the product from Xtremepower is suitable for both options. The system is designed with a 2 feet x 20 feet long solar heating collector that is made of a lightweight, flexible black polypropylene.

The collector has been also designed with a tube construction that creates a larger surface area to optimize heat transfer through the pipes to your swimming pool. The solar heating system is able to raise water temperature up to 6-10 degrees Fahrenheit (depending on solar irradiance values on the location) and works perfectly with most pool pumps.

The Xtremepower solar heater for pool has been designed with high-grade materials that can resist harsh weather conditions. Moreover, the heating system includes a round 1.5” header manifold and is attached with a rubber coupling.

The solar heating system is ideal for above-ground pools below 18 feet (round case) and for up to 350 sq. ft. (oval case), although by adding another solar heater mat, higher capacities can be obtained.

3. Smartpool S601P Solar Pool Heater


Key Features:

  • Fiberglass reinforced over-molded header
  • Heating tubes maximized with a wider area
  • Wind vents included maintaining heating panel integrity

Key Specifications:

  • Increases temperature 6-10°F above standard value
  • Heating panel measures 4 feet wide x 20 feet long
  • Panel area: 80 square feet

Where To Buy

Smartpool offers a remarkable option to the market: A solar heater for inground pool (also suitable for above-ground pools).

The Smartpool S601p SunHeater solar panel uses a direct flow system of water through your pre-installed water pump to make the water flow through the solar collectors to heat the water up to 6-10°F more than its regular temperature value.

The heating collector is 4 feet wide x 20 feet long and can be placed next to your pool or on top of your roof.

The design of the solar pool heater panels has been carefully measured including multiple features that make this product unique among others.

One of these features is related to its fiberglass reinforced over-molded header which provides durability for a long time. Also, the design of each tube has been measured to increase the surface that receives solar radiation and increase temperature values as much as possible.

Keep in mind that to install the Smartpool s601p SunHeater, you need to add an additional SK21 system kit to the purchase.

4. GoPlus Solar Dome

side facing game 4714 solarpro

Key Features:

  • No bypass valve required for pumps up to 1.5HP
  • Ball shape solar collectors
  • Adjustable legs included

Key Specifications:

  • Increases temperature up to 5°F for 10,000 gallons
  • Up to 19 gallons per minute direct flow rate
  • Dimensions: 27.6 x 5.9 x 44.9 inches

Where To Buy

The GoPlus Solar Dome SolarPro ball-shaped solar powered pool heater is a different and innovative solution to heating your swimming pool during the spring and fall seasons.

The SolarPro contour solar pool has been designed for both above-ground and inground pools where high-quality materials allow maximum sun exposure without causing any damages to the product in the long-term.  

There are several amazing features for this product. First, the SolarPro contour solar pool has a completely curved design that increases heat collection when compared with flat-type products. Moreover, the solar heating panel is integrated with adjustable and foldable legs that allow you to set the collector to the optimum tilt to maximize heat transfer to your ground swimming pool.

The Game 4714 SolarPro ground pool solar heater is able to gradually increase the water temperature by 5°F in 7 days for an estimated 10,000-gallon pool, which is enough to extend your swimming during the fall and spring seasons.  This product hasbeen specifically designed to be a solar heater for above ground pools from Intex or a solar heater for inground pools from Bestway.

5. PoolMaster 59026

Key Features:

  • Flat shape pool solar panel
  • Easy to install
  • Suitable for above-ground pools

Key Specifications:

  • Increased heat absorption up to 40% per cycle
  • 41.4-  x 28.8 x 20.5 in
  • Weight: 17.46 lbs

Where To Buy

The  PoolMaster 59026  is one of the available above ground solar pool heaters.

This model has been designed with a flat shape that maximizes heat absorption capacity by 40% per cycle. Using 51-ft. long and 1.2-inch solar coils that are comprised within the product, this small solar pool heater is able to increase water temperature by 5°F in only 5 days.

The product can also be coupled with more heaters to warm up pool water even faster. Keep in mind that using bigger capacity pool pumps without the use of a GAME bypass kit will void its 1-year warranty.

6. SunHeater S240U

Key Features:

  • Easy installation
  • Tube-web-tube design captures more solar heat
  • Made of durable polypropylene

Key Specifications:

  • 2 feet width x 20 feet long
  • Raise the temperature up to an additional 6-10°F
  •  Contains 4 end caps, 2 elbows for flex hose connection, 6 stainless steel hose clamps, 1 roll of Teflon tape, and rubber connector hoses

Where To Buy

The second option of SunHeater is the S240U solar heater for above ground pools. These models have been designed with a 2 ft. width x 20 feet long heater mat that covers a 40 square feet area to provide heat to round pools that go from 12-18 feet and for oval pools of 12-24 feet.

The pool receives warm water coming from the heating collector that is made out of a polypropylene material that will not rust, corrode, or scale — ensuring long-term performance.

These solar heaters for above ground pools will increase the water temperature 6-10°F when properly sized, and they can be installed up to 30 feet away from the swimming pools.

Moreover, the heating collector is easy to install: you will only need to connect the panel with the swimming pool through a hose that will pass through a pool pump and a filter to reach the collectors. If you are looking for a cheap solar pool heater that also has a good performance, then the SmartPool S220 might be for you.


7. Sun Heater

front facing Sun2Solar Ground Mounted Heating

Key Features:

  • Lightweight and flexible
  • Black polyolefin design
  • 5-year warranty

Key Specifications:

  • 2 feet width x 20 feet long
  • Raises temperature 6-10°F above normal values
  • 40 square feet of solar heating mat

Where To Buy

The Sun Heater solar panels for pool heating are the perfect choice for increasing the temperature of your pool water.

This solar heater mat has 2 feet in width and 20 feet in length. This length allows pool water to flow directly through the hot tubs that have been designed for optimum heat absorption resulting in a 6-10°F rise in temperature values when comparing cool water entering the panel system with hot water coming out of the solar heater mat.

A panel array system from Sun2Solar acts as the perfect rooftop solar pool heater since it is easy to install on the roof due to its lightweight and flexibility. Also, the heating panels protect your roof from rain and solar radiation, taking the heat out of your roof and not trapping moisture inside.

Sun2Solar products can be used as solar heater for in-ground pools or above ground pools as well.

8. Doheny’s 5′ x 10′ (Two 2.5 x 10 Panels)

Key Features:

  • Mounting kit included
  • 5-year warranty
  • Diverter valve included

Key Specifications:

  • Two 2.5 feet x 10 feet solar panels
  • Total 50 square feet area
  • Temperature raise up to 15°F

Where To Buy

The Doheny’s polypropylene solar heating collector is a simple but effective choice to warm up your pool water during the swimming season.

The product integrates two 2.5 feet (width) x 10 feet (long) solar panels that, together, add up a 50 square ft. area of heat radiation extraction for your pool. The product is easy to install for above ground pools and is also applicable for in-ground pools.

Moreover, by properly sizing the pool heater, you should be able to obtain up to a 15°F addition in water temperature.

Also, the brand provides a 5-year warranty for each swimming pool solar panel that you purchase which is enough to test the quality of the product. The brand also offers the choice to install the solar pool heater in a sloped mounting racking kit structure that includes the straps, brackets, and screws needed to make the installation. A diverter valve is also included as part of the kit.

9. SOLARPOOLSUPPLY Universal Solar Pool Heater Panel

Key Features:

  • Easy installation
  • Withstands harsh conditions 
  • Quality tube-and-web design

Key Specifications:

  • Size: 4 x 10/2 in header
  • Compatible with any solar pool heater with  round 2.0″ I.D
  • Made from precompounded polypropylene

Where To Buy

SOLARPOOLSUPPLY  is another American company that is focused on providing solar-based technology solutions for pool and water heating for any house.

This solar pool heater has been designed specifically for above ground pools and is able to raise the temperature of water between 10-15°F during the swimming pool season of the year.

Each Sungrabber solar heating system includes two 2 feet width x 20 feet long collectors that are suitable to heat round pools up to 24 feet (using a single solar panel) or 28 feet (using both pool solar panels). If you use more solar pool heater panels, you will be able to increase temperature levels above 10°F easily and faster.

One of the unique features of the Sungrabber product is that the pool heater has a 10-year warranty. This product can be purchased at a reasonable price.

10. 28″x20` Solar Energy Swimming Pool Heater

Key Features:

  • Suitable for both inground and above ground swimming pools
  • Hose adapters and O rings included
  • Roof-type solar pool heater

Key Specifications:

  • Temperature increase between 10-15°F
  • 40 square feet area
  • 24-inch (width) x 20 feet (length)

Where To Buy

This solar pool heater panels are the final option on our list. Designed with a 24-inch width and a 20 feet length to provide a total of 40 square feet area covered by the solar panel, is a good option with reasonable price to pay for pool heating.

The product is suitable as a solar pool heater in-ground product or as an above-ground option. Moreover, the water passes through the collectors and is able to increase temperature values up to 10-15°F according to solar irradiance in the location.

The product has also been designed to work with most pool pumps and is easy to install on the roof. When sizing the number of solar pool heaters needed, keep in mind to have a solar panel area that is located between 50-60% of the pool surface area.

Each product box includes 1 solar panel set, with combination hose adapters and O rings needed for the installation.

Choosing a Solar Powered Pool Heater – 5 Key Features to Look For

view of rooftop solar panels and a swimming pool

Square Footage Coverage

One of the first features that you must dive into is related to the square footage coverage that the solar panel system has.

This is an important feature for many reasons. First, you need to know the amount of surface area that is required to completely open the solar pool heater. Typical area sizes are between 40 and 80 sq. ft. per product, but this will depend on the number of solar panels that you have. Based on this number, you must make sure that you have the available space next to the pool to install the solar heater.

Many pool heaters are also suitable for installations on the roof, especially solar panel type heaters that have a flexible and lightweight design that makes them easy to install on complicated roof surfaces. The installation process of a solar heater should be easy enough to apply for DIY projects, but you can always go to a professional if you feel uneasy on the rooftop.

Even more than just the available space on the roof or in the ground, you must also keep in mind that the amount of heat that the solar collector is able to provide to the pool water is also dictated by the square feet of the heating collector and to the solar radiation available in the area.

According to estimations, the brand could or should provide an average value of heat generated in British Thermal Units (BTUs).  This number will tell you how much heat your ground pool is receiving per day.

Typically, 80,000 BTUs should be enough as to provide a good heating rating for a 24 feet pool. If you want to add more heat to your pool, then you must simply add more solar heaters. 

The rule of thumb here is that you add square footage in solar panel array that represents at least 50% of the surface area of the ground swimming pool

Temperature Rise

The second feature that you must look into is the estimated temperature rise that the solar pool heater will be able to provide.

Solar heaters are designed to provide a specific increase in pool temperature when compared to a ground swimming pool without any solar heating system. Assuming there is proper sizing, the dimensions of the pool change the size of the required solar panel heating system. A much larger solar panel array could become unviable economically, and too short of a solar array may not provide the desired temperature level.

This is why most manufacturers specify the number of solar collectors needed for a specific pool size in order to provide an average temperature increase that is generally located between 5-15°F (additional to the pool’s temperature). This temperature range changes according to the manufacturer, the weather conditions and the pool size as well.  

Mounting Type

Solar pool heaters also have multiple mounting options. Manufacturers may offer a product that can be adjusted for a single or for multiple mounting types. There are mainly three mounting types for a solar pool heater.

The first one is simply flat. In other words, this applies mainly for a solar heater mat (like FAFCO Solar) where you can simply roll out the heater and lay it on the ground next to the swimming pool. This mounting type does not obtain maximum efficiency as the tilt angle is always zero.

The next option is installing a racking system. By placing the solar panel heating system on a mounting racking (like the Smartpool, or the curved Game 4714 SolarPro or a solar dome pool heater), the tilt angle of the array can be adjusted and therefore achieve a higher level of efficiency and heat transfer.

Finally, the rooftop is the last mounting option for a solar pool heater. This option is the one that requires a longer installation but is probably the best regarding the optimization of space and heat absorption.

If the price is reasonable and the installation is feasible, the rooftop option is better. If not, then the next choice would be to install a racking system that is oriented and tilt angle-optimized. If previous choices are not possible, go for the flat option.

Pool Type and Limitations

There are two types of swimming pools: above ground and in-ground.

Each solar pool heater manufacturer designs its product to fit a specific type of pool. The solar heater for the in-ground pool may not be the same for the above ground type. Some brands will offer products that will be suitable for both options, but many others will be restricted to a single type. Keep this in mind.

An additional detail that you must pay attention to is that the solar heaters are also designed to withstand specific water pressure. If you have installed a pool pump that exceeds the allowed horsepower capacity of the solar heater then you will have to install a bypass valve that reduces that water pressure. Otherwise, you could damage the pool heater and void the warranty.


Finally, the last detail that you must look further into is related to a feature that cannot be missing in any product purchase: warranty.

Product warranties for solar pool heaters can go from 2 to 10 years. As you can see, the difference can be very important, therefore, you need to make a balance between price and warranty value provided by the manufacturer.

How Much Should You Expect to Pay for a Top Solar Pool Heater?

The price range for a solar pool heater is quite variable. Many factors need to be considered: manufacturer brand, type of solar heater, materials, size, and warranty.

Therefore, it is hard to make an accurate estimation. However, if we consider an average residential pool we can estimate solar pool heater prices to be located between 100$ and 300$.  Keep in mind that this is the average price for a single unit box, and you may need multiple units for your pool. The average cost of installing a solar pool heating system in the US is between $3,000 and $4,000 according to the Department of Energy.

How to Know What Type of Heater You Need for Your Swimming Pool

solar panels installed on the roof of a house

The first thing that you must have in mind is to check what type of swimming pool you are dealing with.

Above ground swimming pools have an amazing advantage over in-ground pools as the installation process needed is much faster. The filter, water pump, and the heating solar system can be easily connected to the pool through a hose that is exposed to the sun and no complicated installation is needed. Here, the best choice is to simply purchase a mounting racking type solar heater to make the installation easier, faster, and economic.

However, if you have an in-ground pool, opting for a rooftop solar heater might become the best alternative due to space availability, aesthetics, and solar energy harvesting. Installing the pool heater on the roof will maximize all of these variables. Keep in mind that by combining both a rooftop solar pool heater and an in-ground pool model, you will probably need to request help from a solar installer.

In this case, the installation process may be complicated as there may be the need to do plumbing and piping of the lines. It also involves mounting all of the solar panel array on the roof and adjusting the bypass valve to fit the proper water pressure (probably with a solar controller). This water pressure must be strong enough as to go up to the roof, but not strong enough as to damage the solar collector

What Size Heater Should You Buy?

The size of the solar pool heater will depend on several factors: Solar radiation, dimensions of the ground pool, and also the desired swimming season that you want to have.

As we mentioned before, the basic rule of thumb is that the solar pool heater needs to have a square footage that represents at least 50% of the pool square footage. However, this does not ensure that you will reach a nice temperature across the year.

Some regions across the US do not have an attractive solar resource. As you know, the pool heater uses solar energy to warm up the water, if the available solar resource in your location is low, then the heater will need more square footage or time to increase the pool temperature. Moreover, cloudy conditions are also a factor to consider.

Photovoltaic solar panels can still generate electricity even on cloudy conditions as they use the light component of solar radiation (which is still active on cloudy conditions). However, the heat component of solar radiation will be almost inactive during raining or cloudy conditions, therefore you must evaluate how regularly clouds may appear in your location.

Another factor to evaluate is the presence of shades. If one side of your solar collector is irredeemably shaded by a tree, a chimney or any other object, then you must also increase the size of your heating collector.

As we mentioned, every solar pool heater manufacturer designs its solar panel to provide a specific temperature increase (5-15°F) for a specific pool size. 

Most solar pool heaters have standard sizes, meaning 2 ft. x 20 ft. or 4ft x 20 ft. Therefore, as you can see, the size of your heater is not the issue, but the number of solar heaters that you will need to cover the square footage of your pool.

To calculate the number of solar panels that you would need from a specific manufacturer, the simplest approach that you can take is 

Where X is the number of solar panels and Fd is a derating factor related to the percentage of square footage relation between the pool and the panel (minimum 50%, ideally 65%). If you want to use a more precise methodology, you can also check this solar pool heater calculator.

Are Solar Pool Heaters Water-Resistant?

photovoltaic solar panel for heating water in the children's pool

Solar pool heaters do not have any electrical component that could get damaged by the contact with water. Actually, they are completely capable of receiving rainwater on their external surface. In other words, you can have your solar pool heater installed just next to the swimming pool in the backyard where you can also have a barbecue or even a solar birdbath fountain.

If there is any leakage associated with the heater, then it means that there is physical damage that needs repairing. However, it will never be associated with the resistance against water.

The only factor that you must be careful about is related to the water pressure. This is limited by the maximum horsepower that the manufacturer establishes for the pool pump.

5 Tips for Taking Care of Your Swimming Pool Heater

A solar pool heating system should be designed to endure raining and strong winds, however, there are a few valuable tips that you should know about to take care of your investment.

Winterize Your Pool Heater

One of the biggest mistakes that you could make is to leave your solar pool heater out there in the winter. These products are made of polypropylene (plastic) materials that have been tested to endure heat and specific water pressures. The damage caused by freezing water is something that these products are not made for.

To winterize, you must disconnect the pool pump, unmount the solar pool heater, and fully drain it to store it in a safe conditioned space (above 40°F) for winter.

Install the Bypass Valve

Water pressure is one of the limitations of every solar pool heater. The best way to control direct flow and pressure of water is to install a bypass valve. Keep this especially in mind when the pool pump is above the maximum horsepower allowed.

Install a Solar Cover

One of the simplest ways that you can help your solar collector to reach the desired temperature values is to add a solar cover or blanket to your pool. This will keep the generated heat during the night or during windy days.

Clean the Filter Periodically

It’s important to make sure that no object that enters inside the pool, reaches the solar collectors. For this, the filter must be cleaned every once in a while and changed if needed.

Touch Test

The solar collectors are designed to transfer heat to the water that flows through them. Therefore, they should be cool if you touch them. After winterizing and starting the swimming season again, test them during the first week of the season and touch them. If they feel unusually warm, call your installer.

We hope you liked this article. Please rate it or leave us a comment.

Average rating 4.7 / 5. Vote count: 15

No votes so far! Be the first to rate this post.