10 Best Pool Heaters of 2021 Compared & Reviewed

Best Pool Heater

A pool entices its owners all winter long. However, the mere thought of stepping into ice-cold water is good enough to snap you out of the fantasy, unless you have the best pool heater to let you enjoy swimming in winters.

Before you can make a suitable purchase, it is important to know all the varieties of pool heaters available online. These are solar, electric, natural gas, and heat pumps.

You can imagine from their names that they vary in operation. However, the most crucial difference between these models is cost.

In this review, you will learn about the different features of each of these pool heaters followed by some spectacular recommendations. Let’s start.

What to Check Before Buying Best Pool Heater?

​How to Buy the Best Pool Heater
Photo: residencestyle.com

So, we will now proceed with this pool heater review and mention some of the significant tips to help you buy the most efficient pool heater.

1. Type of Pool Heaters

If you have been following our guide since the beginning then you must know about all the different types of pool heaters.

However, we will share a comprehensive theory on each one of it.

Solar Heater

We will start with the most budget-friendly option in the market which is the solar heater. Well, it is run by solar energy.

Used by the solar panels that are installed in a place where there is direct sun, this heater consumes a lot of energy in the daytime and then heats the pool water eventually.

Water is first circulated from the pool into the panels where it is heated up and then recirculated to the pool.

The heater is not recommended for the people that live in wet places that experience rains most of the time of year. It works best in sunny areas.

This can be an auxiliary option but if you like swimming a lot then we don’t really recommend it. The reasons are it is slower than the counterparts plus not as effective.

Our brightest recommendation in solar pool heaters is the Fafco solar pool heater as it is great in performance and comes with a prolonged warranty. 


  • Do not use electricity at all which means no additional operational cost
  • Environment friendly
  • Very durable


  • Very slow in heating up the water

​Natural Gas/ Propane

If you want an uncompromised heater option and are willing to spend a high amount then, natural gas or propane heaters have no substitute.

The heater uses a combustion chamber to heat up the water. The water is passed through a super-hot tube channel and when it returns to the pool, the temperature is already up by 30 degrees.

Now, the drawback is the while these heaters are absolute winners, they come with huge price tags. But, they don’t require a long operational time i.e. you only have to use them for hours before diving inside the pool.


  • Impeccable performance
  • Durable
  • Quick in heating up the water


  • Expensive than the counterparts
  • Not environment friendly because it diffuses harmful gases

​Electric Heater

Well, this is the most common type in this category. Clearly, the electric heater runs on electricity.

These heaters are less expensive and conveniently installed, yet the drawback is that they are not energy efficient. You can expect huge electricity bills. If you don’t mind paying the hefty bills then this heater is for you.

These models are suitable for in-ground as well as above-ground pools.


  • Durable  
  • Don’t release harmful emissions
  • Less expensive


  • Takes a lot of time to warm up the water
  • Not energy efficient

​Heat Pumps

So, a heat pump is based on quite unique phenomenon where the heater pulls warm air from the surrounding and compressor optimize it to the right temperature. Technically, they run on electricity which is used to collect the air.

As a result, the air is heated and sent to the pool water. This way, you enjoy one of the safest and eco-friendly ways to heat up the pool. Irrespective of the pool size, the heat pumps can efficiently work with them.

These are expensive than others however, the efficiency is also worth appreciating. The operation cost is very less.

The Hayward HT21404T pool heater is a suitable choice to make in heat pumps. 


  • Pretty Efficient  
  • Don’t release harmful emissions
  • Less Operational Cost


  • Very expensive
  • Takes a lot of time

Buying Advice

People that on a strict budget can make a choice between solar, natural gas, and electric heaters. While the upfront cost for electric and natural gas heaters is less than the heat pumps, they demand huge operational costs.

At the same time, if you wish to go energy-efficient and require a highly suitable heater then pick the heat pump. But be ready to spend some hefty amount of money on the initial purchase.

2. Size

We would like to elaborate on the point of size with a simple table below. Most of the heaters come with their respective heating performance. From there, you can assimilate the surface area covered by the heater and the amount of water that it is capable of heating.

Size of Heater in BTUs

Surface Area (In Sq. Ft)

Gallons of Water

100,000 – 200,000

Up to 200

1000 – 5000

200,000 – 300,000

200 – 300

5000 – 10000

300,000 – 400,000

300 – 500

10000 – 20000

400,000 – 500,000

500 – 800

20000 – 40000

500,000 or above

800 – 1200

40000 – 80000

3. Type of Pool

There are two types of pools, In-ground and Above Ground. The requirement of heaters is different for both types of pools. However, there are some heaters that are cordial with both types.

In-Ground Pool Heater: Some of the heaters are classified as the best in-ground pool heaters for a reason. Such units are more powerful, have high BTU output, and are energy efficient.

There are no such things as in-ground pool heaters as such because all the kinds such as solar, natural gas, or electric heaters can be installed in such cases.

However, the strength and water heating tendency of a heater makes it suitable for in-ground or above-ground usage.

Above Ground Pool Heater: Identically, all kinds of heaters are suitable for above-ground pools as well.

The capacity of the above-ground pools is usually less than in-ground pools. That is why these require mediocre-sized heaters unless you have a massive pool with a capacity of 40000 gallons.

Mostly we recommend solar pool heaters for above-ground pools.

Buying Advice

For any kind of large pool, we don’t recommend electric heaters. They will charge massively and the power expenses will multiply. Solar heaters are also not suggested for the same because they are not as effective.

4. Price

This section has two main parts. First is the initial expense that comes while purchasing the product. The second is the operational cost of the heater.

Other than the solar heaters, none of the other options come without any operational cost. Electric heaters have a less initial cost, but the bills are increased.

At the same time, you can expect an expense of around $500 per month in the case of gas heaters. The heat pumps also run on electricity, so they also cost a lot later.

10 Best Pool Heaters of 2021 Reviewed




SmartPool S240U

1. SmartPool S240U (Lightweight)

  • Weighs merely 18 lbs
  • Solar heater
  • Comes with all installation accessories
  • Comes with a trilingual manual
Pentair 460736

2. Pentair 460736 (High Capacity)

  • Available in high capacity of 400,000 BTU
  • Natural-gas heater
  • Rotating digital display
  • Compact and quiet
Fafco Solar Pool Heater

3. Fafco Solar Pool Heater (10-year Warranty)

  • Comes with a 10-year warranty
  • Ideal for above ground pools
  • 4 x 20 ft size
  • Comes with all installation tools
EcoSmart Pool Heater

4. EcoSmart Pool Heater (Flow Sensor Technology)

  • Increased reliability with flow sensor technology
  • Electric pool heater
  • Compatible with remote control
  • Digital display
SmartPool S601P

5. SmartPool S601P (Cost-effective)

  • Available at
an economical price Polypropylene heat collector Comes with a
  • direct flow system
  • 4 x 20 ft size
Sta-Rite SR400LP

6. Sta Rite SR400LP (Most-Durable)

  • Dura-glass construction with PVC union connections for durability
  • LED temperature readouts
  • Compact size
  • Propane pool heater
FibroHeat FH055

7. FibroHeat FH055 (Convenient Digital Control)

  • Comes with multiple convenient controls
  • Rugged design
  • Sleek profile
  • Titanium heat exchanger
Hayward H150FDN

8. Hayward H150FDN (Superior Hydraulic Performance)

  • Comes with superior hydraulic performance
  • Environmentally responsible
  • LED digital panel
Jandy JX1400N

9. Jandy JX1400N (Energy Efficient Design)

  • 83% thermal efficiency rating
  • Compact
  • MAX-E-Therm replacement
  • Digital controls
Hayward HT21404T

10. Hayward HT21404T (With Acoustic Compressor Cover)

  • Comes with an acoustic compressor cover
  • UV resistant body
  • Corrosion-resistant evaporator fin
  • Round design for easy fitting

1. SmartPool S240U – Lightweight Pool Heater

SmartPool S240U Universal pool Heater
Photo: SmartPool

  • Type: Solar 

The SmrrtPool Universal is the best solar pool heater and the most lightweight product on our list with a net weight of merely 18-pounds. Therefore, the setting up of this product will be easy. 

There is a polypropylene heat collector that has to be installed in a place where there is direct sunlight for the maximum time. Some people prefer installing it on the roof as well. However, the material could have been better as this is not the highest-grade polypropylene. 

It has a direct flow system in which the water goes to the heater through one hose and after heating up, it gets back to the pool through the second hose.

Attached to the heat collector are the two threaded elbow adapters, four end caps, and 4-stainless steel hose clamps. Plus, you also get a roll of Teflon tape, a rubber connector hose, and a bonus solar pill. It comes with all the necessary installation accessories. 

Also, there is a trilingual installation manual available in English, French, and Spanish languages to help you follow the instructions. 


  • Most-lightweight product
  • Economical
  • Comes with a detailed manual in multiple languages
  • Comes with all installation accessories


  • The material could have been better

2. Pentair 460736 – High Capacity Pool Heater

Pentair MasterTemp High Performance pool Heater
Photo: Pentair

  • Type: Natural gas
  • Heating Performance: 400,000-BTU

The MasterTemp series has a variety of pool heaters that vary in their heating performance. This product comes with the largest capacity of 400,000-BTU which can warm up 20,000-gallons of water. 

It is suitable for large pools. The model has got a tough exterior and digital controls. The system is quite easy to operate due to hot surface ignition, push-button, and digital controls.  

Plus, there is a rotating digital display to help you see the settings conveniently. This natural gas heater is quiet in operation and compact to fit anywhere. 

The operating mechanism is completely user-friendly. You can ensure safe operations through a couple of features such as a water pressure switch that sense the running of the pump to prevent overheating.

Of course, the cost of this product is too high. Plus, there is no warranty with this model. 


  • Huge capacity
  • Quiet in operation
  • Digital controls
  • Tough exteriors


  • No warranty
  • Very expensive

3. Fafco Solar Pool Heater – Pool Heater with 10-year Warranty

Fafco Solar Pool Heater For Above-Ground Pool
Photo: Fafco

  • Type: Solar 
  • Heating Performance: 80000-BTU

The USP of Fafco solar heater is that it comes with 10-year warranty. This means that this product is your safest bet.

It is available insole size of 4 x 20-feet. This solar heater comes with a great heating tendency. It is ideal for above-ground pools of small sizes.  

There is a polypropylene heat collector that has to be set on the ground, roof, or anywhere where there is constant exposure to the sun. The pool pump circulates pool water through the heat collector and thus, the water in the pool warms up.

This can only provide optimum performance when the heat collector is in constant sunlight from 10 am to 4 pm. It has simple working as any other solar pool heater. 

It comes with a 2, a 6-feet long hose with 4 clamps, an integral bypass valve, and all other important hardware to install the heater. We don’t suggest self-installation because it will be tricky, especially for first-time users.

Also, among the competitive solar heaters, this product is a bit overpriced. 


  • Comes with 10-year warranty
  • Dedicated product for above-ground pools
  • Comes with all installation accessories
  • Simple working


  • Installation is difficult
  • A bit expensive

4. EcoSmart Pool Heater – Pool Heater with Flow Sensor Technology

EcoSmart US Electric Pool Heater
Photo: EcoSmart

  • Type: Electric 
  • Heating Performance: 92,000-BTU

The EcoSmart electric pool heater is a great choice to make if you don’t mind spending huge operational costs. It comes with flow sensor technology that increases reliability by keeping the accidents at bay.

The heating performance of this product is 92000-BTU. This means that it can only heat water up to 5000-gallons.

This is suitable for small pools or spa tubs. The simple heater has a working mechanism quite similar to any water heating unit installed in your house.

The digital display helps in keeping an eye on the water temperature. Plus, you can digitally increase the temperature on an increment of 1-degree through the remote control.  

This is a durable machine and has a lot of fancy features to lure buyers. However, the small heating performance can be a concern for many people.

You can rather use it as a backup heater or with a heat pump to enhance its performance.


  • Flow sensor technology
  • Comes with a remote control
  • Digital displays
  • Durable


  • Low heating performance

5. SmartPool S601P – Best Cost-Effective

SmartPool S601P Solar Pool Heater
Photo: SmartPool

  • Type: Solar 

If you are on a budget then this solar pool heater is the best thing that you can install to keep pool water warm.

It comes with a polypropylene heat collector. You have to install it in the direct sunlight area. This way, the heat is constantly collected and as a result, the performance of the heater enhances. Also, since high-quality material is used in construction, this is a durable product. 

The 4 x 20-feet of solar panel is great for massive heat collection. Also, it is suitable to be used with any in-ground or above-ground pool

Also, this model comes with a direct flow system that has a header hole for each heating tube. This way, the water is collected very easily. 

The installation kit is sold separately, and you won’t get it with the package. This means that you have to spend a few extra dollars on the kit.


  • Economical pool heater
  • Very durable
  • Direct flow system
  • Suitable for in-ground and above ground pools


  • Installation kit is not included with the product

6. Sta-Rite SR400LP – Most-Durable

Sta-Rite Max E-Therm Pool Heater
Photo: Sta-Rite

  • Type: Propane   
  • Heating Performance: 400,000-BTU

Sta-Rite has manufactured the finest series of the best propane pool heaters in its class. It is extremely durable due to dura-glass construction that handles heat and weather elements effortlessly. 

With a heating performance of 400,000 BTU, this is one of the most powerful models in the market.

It has the tendency to heat 20000-gallons of water. This is a compact design for retro-fit installation.

The features include an LED temperature readout with dual thermostat controls, temperature safety lockout, and a 6-position control panel. This is suitable for indoor and outdoor installation.

The model is not environmentally friendly because of the emission of gas. Plus, the operational cost is also high.


  • Durable construction
  • Compact
  • Dual thermostat controls
  • LED temperature readouts


  • Not environment friendly
  • High operational cost because propane has to be refilled every month

7. FibroHeat FH055 – Best with Convenient Digital Control

FibroHeat FH055 In-Ground Pool Heater
Photo: FibroHeat

  • Type: Electric  
  • Heating Performance: 55,000 BTU

FibroHeat electric pool heater is made with advanced technology and has an easy set digital panel that gives quick control to a variety of features in this model.

The heating performance of 55000 BTU. This means that it can heat up at least 1000 gallons of water.

Mostly, you can use it with the spa tubs but this is also suitable for small in-ground pools. The titanium heat exchanger enhances the performance of the heater and makes it energy efficient as well. 

This is a sleek product that you can install outdoor or indoors. The digital display helps in keeping a check on the water temperature and other essential features of the heater. Plus, the rugged body is enamel coated to endure outdoor abuse. 

Unlike other electric heaters, this one is energy efficient and thus, the operational cost comes down.

However, you won’t be able to use it with large pools. Plus, as per the heating performance, the price is quite a lot.


  • Comes with easy digital controls
  • Slim and rugged design
  • Energy efficient help you save money on electricity bills


  • Low heating performance
  • Very expensive

8. Hayward H150FDN – Best with Superior Hydraulic Performance

Hayward Universal H-Series Pool Heater
Photo: Hayward

  • Type: Natural Gas, Propane  
  • Heating Performance: 150,000-BTU

The key thing about this model is the patented polymer header and bypass design that gives ultimate hydraulic performance for more reliability and efficiency. 

The heating capacity of this model is 150,000 BTU which means that it is only suitable for small pools or spa tubs. 

The LED design panel not just helps in accessing the features, but also shows the functions in use for quick monitoring. 

The installation is quite difficult, so you may need to call a professional. This model is quite durable and manufactured with high standards.

As far as being environmentally friendly is concerned, this model comes with a low-No emission technique which means that this will not pollute the environment. Also, it comes with a year-long warranty. 


  • Superior hydraulic performance
  • LED control panel
  • Safe for environment
  • Comes with 1-year warranty


  • Installation is difficult

9. Jandy JX1400N – Best Energy Efficient

Jandy JX1400NPro Series Pool Heater
Photo: Jandy

  • Type: Natural Gas  
  • Heating Performance: 400,000-BTU

If you are concerned about the environment then don’t be because this model comes with a low-No emission system and is 83% thermal energy efficient, despite being a natural gas heater.

It comes with a heating performance of 400000-BTU. It can warm up 20000-gallons of water easily. Also, this model gives you quick plumbing flexibility with Max-E-Therm replacement. It does not require any plumbing as such. 

This is an ultra-compact machine, suitable for both, indoor and outdoor usage. There are other attractive features to this product such as 180 degrees rotatable top that completely abolishes the need for rotating headers.

It has digital controls, a rotating top for better accessibility, rugged housing, and corrosion-resistant sensors that make this product more appealing to buyers. However, this model lacks in warranty.


  • Energy-efficient and environment-friendly
  • Digital controls
  • Plumbing flexibility
  • Rotating top for better accessibility


  • No warranty

10. Hayward HT21404T – Pool Heater with Acoustic Compressor Cover

Haywards Heatpro Titanium Heat Pump
Photo: Hayward

  • Type: Electric
  • Heating Performance: 140,000-BTU

The Haywards heat pump is a combination of excellence and diligence. In order to ensure that the heater doesn’t cause a lot of noise, there is an acoustic compressor cover and profiled fan blade. It is super silent while heating up the water.

This model comes with a heating performance of 140000-BTU. You can expect up to 5000-gallons of water to be heated effortlessly.

There is an ultra-gold corrosion-resistant evaporator fin that ensures the durability of the product. With the titanium heat exchanger, the maximum amount of heat is transferred to the pool in the most reliable way.

You should also not be worried about the outer body of the heaters because of the double injection UV-resistant body. Also, it is available in a round design to conveniently fit on the equipment pad. 

No wonder the quality of this model is great, but the size is not suitable for in-ground pools since they have more water. Thus, the performance will be hampered.  


  • Comes with acoustic compressor cover for quiet working 
  • UV resistant body
  • Durable and tough
  • Easy to fit 


  • Capacity too low to suit in-ground pools


So, we would like to conclude our pool heater review by saying that there are various options available in the market, but you cannot rely on them all.

The Pentair 460736 pool heater is an absolute favorite choice for those with large capacity needs. It is available in 400,000-BTU heating capacity.  

If you want to go with a natural gas pool heater, without compromising with the environment and by keeping the maintenance cost low then the finest option is the Hayward H150FDN pool heater.