While a backyard pool can be refreshing on a hot summer’s day, water that’s too cold can be downright shocking. Getting a pool to a comfortable temperature can be a challenge, especially in early summer or if the pool happens to be in a shady spot. Fortunately, there are solar pool heaters that can warm up chilly waters and end the shivering.
These heaters consist of large panels that sit on the ground or mount to the roof of a house. Water is pumped through a webwork of channels that run through each panel, warming it with the heat of the sun before it’s pumped back into the pool.
Since these solar pool heaters require no electricity and can be installed by a DIYer, they are also an economical means of warming up a frigid pool. This guide describes important features to consider when shopping for a solar pool heater and includes details about some of the best solar pool heaters on the market.
- BEST OVERALL: Smart Pool S601 Pool Solar Heaters
- RUNNER-UP: Fafco 10028 Universal Solar Panel Heating Kit
- BEST BANG FOR THE BUCK: Goplus Solar Dome Swimming Pool Heater
- BEST FOR ABOVE-GROUND: GAME 4721-BB SolarPRO Curve Solar Pool Heater
- BEST VERSATILE: SunHeater S120U Universal Solar Pool Heater
- BEST EASY INSTALLATION: vidaXL Pool Solar Heating Panel
- BEST FOR INGROUND: SolarPoolSupply Pool Heater System Kit
- ALSO CONSIDER: FlowXtreme NS1002 Flat-Panel Solar Heater
What to Consider When Choosing the Best Solar Pool Heaters
There are a number of important factors to consider when shopping for the best solar pool heater, including pool size and type as well as each heater’s durability and installation method. Ahead learn more about these and other important attributes of solar pool heaters.
Pool Type
Whether you are looking for a pool heater for above-ground pool use or one for an in-ground pool is one factor that can help narrow the field of options. Solar pool heaters are designed for either in-ground or above-ground pools, and some can work with both types. A small freestanding solar pool heater may be all that’s needed to adequately heat a small above-ground pool, while a large inground pool may demand a large solar heater that mounts to the roof of a home.
Since solar pool heaters work by attaching to the pool’s existing pump, it’s important to purchase one that is rated to work with the pool type. Most pool pumps are designed to work with either inground or above-ground pools but not with both types. Most inground pools use 2-inch fittings, while most above-ground pools use 1.25- to 1.5-inch fittings.
Types of Solar Pool Heaters
Another way to narrow down the search for a pool heater is to decide which type of solar pool heater is best suited for the pool. Solar pool heaters come in three different types: flat-plate, evacuated tube, and batch collectors.
- Flat-plate: This type represents the most common solar heating option for pools. A flat-plate collector consists of a large flat sheet of black polypropylene or hard plastic that absorbs the sun’s heat. The panels are typically mounted to the roof of a home or a rack on the ground. Some also come as freestanding units that are supported by a frame with a clear plastic or glass top and legs that allow the user to adjust the heater’s angle. The panels are connected to the pool’s pump via plumbing and tubes. Water is pumped through channels that run through each panel, heating the water as it circulates through before it is sent back to the pool.
- Evacuated tube: Evacuated tube consists of parallel rows of glass tubes that contain a metal heat pipe that’s attached to a fin that absorbs heat from the sun. The fin then transfers heat to fluid in a metal collection tube and warms it. This type gets its name from the glass tubes, which are vacuums since the air has been evacuated from them.
- Batch: A batch collector consists of a water tank or tubes placed inside an insulated box. Water in the tank or tubes is heated by the sun before being recirculated back to the pool.
Pool Size
Since it takes more energy to heat a larger pool than a smaller one, it’s vital that the solar pool heating system is large enough to capably warm the amount of water in the pool. Typically, the surface area of the solar pool heater should equal 50 to 100 percent of the surface area of the pool to effectively warm it.
Pools located in regions where it’s cooler or cloudier require a surface area that is closer to 100 percent of the pool’s surface area, while a smaller system will suffice for warmer and sunnier climates. Solar pool heaters with larger surface areas are better able to extend the pool season by keeping the pool water warm even through early fall.
Mounting Type and Installation
Solar pool heaters come in a variety of mounting options. Small models consist of rigid square-shaped or round frames, which can either be mounted to a roof or be installed as a stand-alone unit. Many rigid solar pool heaters have adjustable legs that allow the user to aim the panel to absorb as much sunlight as possible.
Large solar pool heaters consist of panels that must be mounted to a structure, which is typically either a rack that sits on the ground or the roof of a home. Most large solar pool heaters require the user to purchase installation kits and racks separately, which can add to the overall cost.
Temperature and Efficiency
A solar pool heater’s ability to raise the temperature of the water is dependent on a variety of factors, including the heater’s surface area as well as how many hours of direct sunlight the heater receives on a daily basis. On a cloudy day, a solar heater will have no effect on a pool’s water temperature.
Usually, a heater’s ability to affect the temperature of the pool water depends on the size of its surface area. When sized properly, a solar water heater can warm the temperature of a pool by as much as 10 degrees over a period of several days.
Material and Durability
If you’re wondering, “How much is a pool heater?” it’s important to factor in the durability of the materials and design. Most solar pool heaters consist of black polypropylene, which does an excellent job of absorbing the sun’s heat. Polypropylene is also flexible and fairly lightweight, which makes it easier for a DIYer to mount it to a roof than a large rigid solar panel.
Although polypropylene is impervious to water, the material is susceptible to damage from UV rays. For that reason, quality solar pool heaters use polypropylene treated with a stabilizer that protects it from the harmful effects of UV rays. This protective layer gives it an average lifespan of 15 to 20 years.
Smaller stand-alone models designed to sit on the ground consist of plastic or polypropylene tubing encased in a weather-resistant box with a metal frame and glass or translucent plastic cover.
All solar pool heaters need to be cleaned regularly to prevent debris from collecting around or on top of them. It’s also important to drain a solar pool heater before freezing temperatures arrive in the fall or winter to prevent damaging the tubes.
Our Top Picks
The list below includes some of the top inground and above-ground pool heater options. These models are capable of warming pools by as much as 10 degrees Fahrenheit and can be installed by a capable DIYer.
Photo: amazon.com
With its ability to heat a pool by 6 to 10 degrees Fahrenheit, this solar pool heating system from Smart Pool is one of the most effective solutions for warming up a cold pool. The Smart Pool system consists of a 4-foot-wide by 20-foot-long polypropylene panel, which is 80 square feet of coverage. This large size makes it suitable for pools with up to 130 square feet of surface area.
The system uses the pool’s existing water pump to move water through a series of tubes in the panels. The tubes heat the water as it passes through before pumping it back into the pool. While the system is effective, it does require the purchase of a separate installation kit to mount it to the roof.
Product Specs
- Size: 4 feet by 20 feet
- Type: Flat plate
- Installation: Roof or rack
Pros
- Large surface area for inground and above-ground pools
- Easy to install
- Uses pool’s existing pump
Cons
- Installation kit is sold separately
Photo: amazon.com
With its large surface area, this solar panel heating kit from Fafco is capable of warming a lot of water. Designed to serve as an above-ground pool heater, the 24-foot-long and 4-foot-wide set of panels produces enough heat to raise a pool’s water temperature up to 10 degrees Fahrenheit in an 8,000-gallon pool.
Installation is easy as the heating kit can lay flat on the ground or be mounted to a rack. Similar to other flat plate solar heaters, it works by warming water as it is pumped through a series of channels that weave through the panel. The Fafco system also includes a conveniently integrated valve that bypasses the solar panel on cloudy days or when warming is not needed.
Product Specs
- Size: 4 feet by 24 feet
- Type: Flat plate
- Installation: Ground or rack
Pros
- Large surface area capable of warming an 8,000-gallon pool
- Bypass valve can shut off warming cells
- Easy to install
Cons
Photo: amazon.com
Most solar pool heaters require a lot of space to effectively heat water, making them an unsightly addition to one’s yard or roof. At just 22.5 inches by 22.5 inches and 8.5 inches tall, this dome-style model is a compact option for above-ground swimming pools. It consists of coils that wrap in a spiral shape on the inside of the dome. The clear plastic cover traps heat inside the dome, heating the water as it flows through the coils.
Like other solar heaters, it connects to a standard pool filter. It produces enough warmth to heat a 6,000-gallon pool by 5 to 10 degrees Fahrenheit. This system is also expandable, allowing the user to add multiple domes to increase its heating power.
Product Specs
- Size: 22.5 inches by 22.5 inches
- Type: Dome-shaped flat plate solar heater
- Installation: Freestanding
Pros
- Small size makes it less conspicuous
- Adjustable legs
- Durable rigid construction
Cons
- Not as much heating ability as larger solar pool heaters
Photo: amazon.com
With its freestanding design, this curved model is ideal as a pool heater for an above-ground pool. It features a rigid, curved shape with two adjustable legs that allow the user to angle it toward the sun for maximum effect. Using a standard above-ground pool water pump, water is circulated through the network of channels built into the heating panel where it is warmed before returning to the pool.
The pool heater is capable of warming an 8,000-gallon pool by 5 degrees Fahrenheit in about 4 days. It is just 28 inches by 45 inches, making it a more compact option than larger systems that must be mounted on a roof. This system is also expandable; hook multiple heaters together for more warming power.
Product Specs
- Size: 28 inches by 45 inches
- Type: Flat plate
- Installation: Freestanding
Pros
- Compact size ideal for smaller above-ground pools
- Can be expanded
- Adjustable legs allow the user to aim it toward the sun
Cons
- Warms water slowly over a period of days
Photo: amazon.com
With its ability to mount just about anywhere, this solar pool heater is one of the most versatile options for warming a cool pool. It consists of a 2-foot-wide by 20-foot-long strip of polypropylene with multiple channels woven through it. The heater works with a pool pump, which forces water through the channels where it is warmed by the sun before being directed back into the pool.
This model can be used with both inground and above-ground pools and can be installed on a roof, a rack, the ground, or even a fence. With its 40-square-feet surface area, it’s capable of raising the temperature in a 15-foot round pool or 12- by 18-foot oval pool between 6 and 10 degrees Fahrenheit. Additional SunHeater pool heaters can be added to the system to heat larger pools.
Product Specs
- Size: 2 feet by 12 feet
- Type: Flat-plate
- Installation: Ground, roof, or rack
Pros
- Works with inground and above-ground pools
- Can be set up in multiple locations
- Easy to install
- Large surface area
Cons
- Expensive compared with other pool heaters
Photo: overstock.com
With its stand-alone design and adjustable legs, this pool solar heating panel is one of the easiest to start running quickly. Simply use its adjustable legs to set up the panel to face the sun, then connect the hoses to a standard pool pump. The water is heated as it circulates through the panels before being directed back into the pool.
With its 30-inch by 30-inch size, this heater is large enough to raise the temperature in a small pool by up to 5 degrees Fahrenheit. It’s also easy to add additional panels to increase its heating power. Its legs can be raised or lowered to adjust the angle of the panel between 40 and 60 degrees Fahrenheit, so the user can direct it to receive maximum sun exposure.
Product Specs
- Size: 29.5 inches by 29.5 inches
- Type: Flat-plate
- Installation: Stand-alone
Pros
- Easy to install
- Adjustable angle
- Durable construction
Cons
- Small surface area doesn’t heat as much water as larger models
Photo: amazon.com
Large in-ground pools require a solar heater with a lot of surface area. With its four 4-foot by 10-foot panels, this pool heater kit provides 160 square feet of heating surface, which is enough to warm a pool with up to 260 square feet of surface area. Each polypropylene panel comes equipped with a dense network of channels that heats water as it flows through them.
With a large surface area, these panels are intended to be mounted to a rooftop. The kit includes all the necessary pieces needed to secure the panel to the roof and make connections to the pool’s water pump. This versatile kit comes in sets of four, six, seven, eight, and nine, allowing the user to customize it to suit the size of the pool.
Product Specs
- Size: Four 4-foot by 10-foot panels
- Type: Flat-plate
- Installation: Roof
Pros
- Large surface area can heat a lot of water
- UV-resistant polypropylene construction
- Includes all required materials for roof installation
Cons
- Demands a lot of space
- Expensive
Photo: amazon.com
This flat panel solar heater consists of a collection of solar coils that heat water as it’s pumped through the system. It includes two hoses and 1.25- and 1.5-inch attachments, making it easy to tie into a pool’s existing filtration system. Built-in legs allow the user to adjust its angle to face toward the sun while a plexiglass cover creates a rigid shape that makes it easy to mount this model on the ground.
Each panel is 41 inches long and 29 inches wide, which is enough to warm up a small above-ground pool. Multiple units can be connected with the purchase of a bypass kit to increase its warming power.
Product Specs
- Size: 29 inches by 41 inches
- Type: Flat plate
- Installation: Freestanding
Pros
- Durable rigid construction with plexiglass cover
- Adjustable legs
- Expandable
- Compact size
Cons
- Doesn’t heat water as well as larger models
Our Verdict
With a large surface area that makes it suitable for both above-ground and inground pools and versatile installation options, the Smart Pool S601 Pool Solar Heater is a worthy choice for most pool owners who want to warm up a chilly swimming pool. Those looking for an affordable and more compact option for a small above-ground pool may want to consider the SunHeater S120 Universal Solar Pool Heater.
How We Chose the Best Solar Pool Heaters
We used several criteria while reviewing dozens of solar pool heaters for our list. Since the surface area of a solar pool heater determines its ability to warm water, we chose only large models with 40 or more square feet of surface area for our inground pool selections. We selected more compact stand-alone models for our above-ground pool categories. We also leaned toward solar pool heaters that can be daisy-chained together to expand their heating ability.
Durability is also key, so we selected models that can hold up to constant exposure to UV rays as well as severe heat and cold. Finally, a solar pool heater that is relatively easy to install is preferred by many, so we stuck with those that can easily integrate with a pool’s existing pump system while being easy to mount to a roof or a rack.
FAQs
If you’re wondering how a solar pool heater works or whether it can keep a pool warm in cold weather, then read on for answers to these and other commonly asked questions about these devices.
Q. How do solar pool heaters work?
A solar pool heater consists of a large dark-colored panel that can absorb the heat of the sun. These panels have a series of channels and two valve openings. The openings are connected to the pool pump, which sends water through these channels. As the water flows through, it’s warmed by the sun before exiting through the panel and returning to the pool.
Q. What are the benefits of solar pool heaters?
A solar pool heater can warm pool water by as much as 10 degrees Fahrenheit without using any electricity.
Q. How many solar panels does it take to heat a swimming pool?
That depends on the size of the swimming pool. Generally, a solar panel’s surface area should be at least 60 percent of the pool’s surface area to adequately warm it.
Q. What size of tubing is good for a solar pool heater?
Unless the pool pump uses small diameter plumbing, use 2-inch plumbing tubing for a solar pool heater as that’s the standard size for most pool pumps.
Q. Are solar heated pools warm in winter?
Solar pool heaters can generally heat pool water by up to 10 degrees Fahrenheit beyond its normal temperature. Unless you live in a warmer climate, such as Florida, pool water can drop below 60 degrees Fahrenheit in the wintertime, which is beyond a solar pool heater’s ability to warm it to a comfortable temperature.
Q. How long does pool solar heating last?
Most solar pool heaters will last for 10 to 15 years before the material begins to break down due to damaging UV rays and exposure to extreme temperatures.
Q. How do I keep my solar pool heater from freezing?
To keep your solar pool heater from freezing in the wintertime, make sure to completely drain it in the fall when it’s time to winterize your pool.
