Best Swimming Pool Heater | Expert Reviews & Buyers Guide

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Finding the best pool heater for you installation needs some research and a little planning.

A swimming pool heater is a pretty major financial investment and in this review article you’ll find all the tools you need to make make the best buying decision.

Our expert team have curated a list of this years best heaters.

Of course there are a number of ways to heat your pool. In this article we’re just going to take an in depth look at gas swimming pool heaters and energy efficient pool heat pumps.

We’ll show you how to determine the pool heater size you need in BTUs  to get the water up to your required temperature. Then our experts will show you the best strategies to minimise heat loss.

It’s possible to save a massive 70% on your gas energy bills and we’ll show you how.

Let’s dive straight in …..

We hope you take the time to read the whole article especially our advice on choosing the best pool heater for your installation. If you’re in a rush then just click on the links below to our recommended heaters.

SWIMMING POOL HEATER REVIEWS

Haywards Universal H- Series

BRILLIANT ALL ROUND HEATER

At a Glance

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Buying any Hayward product means you’re getting leading edge technology and great build quality.

The Haywards Universal H Series range of natural gas swimming pool heaters can effectively heat all sizes from the modest through to the down right indulgent.

The heating capacities may be different but each model in the H range features the same state of the art features and build quality.

At the heart of the pool heater is the Cupro-Nickel heat exchanger manufactured specifically for exceptional durability and corrosion resistance. Insulated combustion chambers combine with stainless steel burners to complete the highly energy efficient power to the heater.

No wind stack need be installed with the H-Series heaters. They use a forced draft system through a heat exchanger. This eliminates outside weather conditions that can sometimes affect heating efficiency.

A pretty well un-matched hydraulic design reduces circulation pump run time, the heated water is pumped into your pool fast so reduced energy costs.

Easy and lightweight installation. The H-Series has a choice of left-side or right-side electric, gas and water connections.

Available for natural gas or propane. The brilliant hydraulic performance, high energy efficiency and a Low NOx profile makes this a very compelling pool heater indeed.

Range Options: 150K, 200k, 250k, 400k BTUs

Owners Manual:

Hayward H- Series Manual

Pentair 460730 MasterTemp Heater

At a Glance

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These Pentair High Performance pool heaters are the foot soldier of the pool heating world. Solid, and reliable, they get the job done efficiently with no fuss.

A surprisingly small heater, that means they’re an easy retro-fit.  All models in the range measure 21L x 21W x 28H, as the power goes up the outside dimensions remain the same.

When fitted with a heavy-duty (HD) unit with cupro-nickel exchanger it will stand up to the harshest environments, like low pH and high flow.

All models are fitted with Dual Temperature controls to warm either your pool or your spa. Hook it up to a spa and you’re be hot tubbing at 104º in minutes.

Super quiet when it’s running so it won’t intrude on your poolside parties. It carries a low NOx certificate, it’s kinder to the environment than many other heaters.

If you’re looking for a real energy efficient gas fired swimming pool heater then this one is hard to see past.

Pentair have an enviable product pedigree in the pool industry,  however their technical support and customer service can sometimes be just mediocre.

Range Options: 175 to 400,000 BTUs plus two ASME models

Owners Manual: 

Pentair MasterTemp Heater Series

Raypak Gas Pool Heater

At a Glance

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Raypak have incorporated many years of commercial boiler experience into the design of this line of domestic pool heaters.

There’s a lot of nice features built into this range, we particularly like the remote compatibility with most pool control systems that allows the owner to seamlessly integrate the heater into their pool setup.

The easy to read digital control panel also gives an abundance of useful information for the owner or technician. Flame strength and run times are monitored, and a voltmeter can be displayed too if required.

A cool feature is the heaters on-board diagnostic controls, troubleshooting has never been easier, no codes here just plain English.

So plenty of fancy footwork on the digital side but what about the hardware? 

Well as you’d expect from a company with the pedigree of Raypak they’ve got you covered. Our highlighted model has the more economical copper heat exchanger ( Cupro-Nickel exchangers are available if preferred ) with stainless steel burners and heat shield. It can run off 120 or 240v.  Connectivity to the right or left side of the heater.

If a pool heater can be elegant then the Raypak is as close as we’ve seen. It’s not style over substance This heater is built to last.

Range Options: 206k, 266k, 366k, 406k BTUs

Owners Manual: 

RayPak Gas Pool Heater Series

Sta-Rite Max-E-Therm Gas Pool Heater

At a Glance

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This is a great little heater.  The Mike Tyson of pool heaters in fact. It’s small but packs an enormous punch

It does remind us of a wood burning stove that’s where old style finishes.  This swimming pool heater is packed with up to the minute, state of the art features. Available for natural gas or propane installations.

The internals are tough too, a heavy-duty cupro-nickel heat exchanger will cope with harsh hi-flow applications and out of spec pool water and the brilliant PMG burner technology means it doesn’t require an outdoor draft hood.

We particularly like the  top mounted digital controls. They can be swivelled a convenient 360º for easy viewing. 

The heater housing is made from Dura-Glass, that’s a thermoplastic resin exclusive Sta-Rite. It easily handle all the summer and winter elements. It simply can’t rust out.

Sta-Rite is a company with a long history of making great boilers and pool heaters.  You’re in safe hands with this range.

Range Options: 200k, 330k, 400k BTUs

Owners Manual: 

Sta-Rite Max-E-Therm Manual

Raypak Heat Pump for In Ground Pools

EXCELLENT ALL ROUND HEAT PUMP

At a Glance

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If a pool heat pump can be awesome then this Raypak range is. They’re the HumVee’s of the pool heating world. An uncompromising design and a powerful performance.

You don’t have to worry about a roaring V8 with this installation though. One of Raypak’s top priorities is to produce a quiet running unit, so the whole range is fitted with acoustically engineered swept blade fans, tuned for each heat pump size. So more air over the coil, greater efficiency and almost inaudible.

They’ve not stopped there, the base has a sound deadening material to minimise vibrations and keep sound levels to an absolute minimum.

These pool heat pumps use Copeland scroll compressors too, again super quiet when compared to piston compressors. They’ve very few moving parts, so they’re highly efficient and almost indestructible which for an owner is pretty comforting.

All this quality hardware needs a great control panel and the Raypak interface is intuitive and easy to access.

You have total control over your pool and spa settings. Just dial in the temperatures you want and the Raypak heat pump will take care of the rest. A nice and unique feature is the Solar Priority Control which like it sounds prioritises solar as the primary heat source and turns the heat pump into a back up booster.

Of course it has a built in timer but it can also be integrated into other remote controlled systems if desired.

The whole package is wrapped up in a DuraSteel cabinet that’s zinc chromate plated and polyester powder coated. It’s non-corrosive and in fact much more durable than plastic that is used by some other manufacturers.

Looks like a HumVee but runs like a Cadillac. That’s why this is our top pool heat pump pick.

Hayward HeatPro Electric Pool Heater

At a Glance

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The popular Haywards heat pump range is suitable for in ground and above ground pools. It’s been designed for easy installation and ease of use.

In this model Hayward have paid particular attention to minimising the sound impact when it’s running. A carefully profiled fan blade and an acoustic compressor cover combine for a very low audible impact indeed.

This is particularly important for above ground pool installations where the heat pump is generally adjacent to the pool.

The entire range is fitted with titanium heat exchangers so you can expect them all to have excellent resistance to chemical corrosion and salt water systems. A corrosion resistant evaporator coil is also fitted so the heat pump will stand up well to living in a coastal environment.

The injection molded panels will stand up well too, they’re not going to deteriorate or rust and are UV resistant so the pump should keep its fine bright livery without fading.

For greater efficiency the 2in x 2 1/2in CPVC union plumbing can be increased if desired although for most home installations it’s probably not worth doing.

A typical Hayward pool product, well made, well engineered and built to last. Nothing not to like here.

Range Options: 95K, 110k, 140k BTUs

AquaPro Swimming Pool Heat Pump

At a Glance

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A company specialising in pool heater pumps, Aqua Pro offers a really ample range, with BTU outputs that cover pool sizes from 13,000 up to 35,000 gallons.

Most models in range are fitted with titanium heat exchangers, with rugged housings and fittings.  Aqua Pro heat pumps are renowned for delivering trouble-free, long-lasting service. But in the event you do need to diagnose an interruption in service the smart control panel will point you to any potential problem or inefficiency within the pump. A useful enough feature but not often needed.

This heat pump also has a number of other innovative features including an auto defrost function that allows it to work in temperatures as low as 38ºF. Conveniently its also been programmed to be compatible with all known remote systems too.

Your spa and pool water temperature can be built separately by simply toggling between the two on the digital control panel and let the dual thermostats take care of the rest. It’s nice and quiet when its running so your you’ll just hear the spa bubbles when your having a relaxing soak.

All models are fitted with dual temperature controls for your pool or spa up. You can also specifically choose the best temperature for you with its high temperature lock-out safety feature.

All in all a nice pool heater package at a really competitive price.

AquaCal Heatwave Electric Pool Heater

BEST FOR VARIABLE SPEED PUMPS

At a Glance

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AquaCal has been in the business of producing quality pool equipment since 1981. They make their swimming pool heat pumps right here in the United States. 

All heat pumps in the Heatwave range feature Therm-O-Link titanium heat exchangers and compressors. It’s a patented technology that creates a rugged, durable and super cost efficient heat pump that’s pretty much impervious to harsh chemical environments.

If you run two-speed or variable speed pump then the Heatwave only produces 1 psi at 30 gpm so it should be compatible with your system.

A nice control panel with large easy to read blue LED script and an onboard self diagnostic center.

It’s housed in a UV resistant plastic cabinet and should be impervious to solar deterioration. So it’s rust proof, fade proof and crack resistant. There’s also an easy access panel for cleaning and servicing.

PLANNING A POOL HEATER INSTALLATION

When they’re listed out it seems like there’s a lot of things to think about before buying your swimming pool heater. 

Most of the things on this pre-buying checklist actually check themselves. Don’t worry we’ve covered everything in the rest of the article to help you tick off the rest.

If you’re simply replacing a pool heater and you’ve been happy with the way the old one has performed then it’s just a “shoe in”. Out with the old and in with the new. At least the water and gas pipes are there, and if you’re very lucky they may line up.

Of course if your building out a new pool installation then it’s even easier. Retro-fitting a pool heater is where you need to take a little time to carefully consider and plan.

Natural Gas or Propane ?

This question usually answers itself. If you have natural gas running to your home then you’ll probably pick natural gas.

Natural gas is also normally cheaper than propane but one of the benefits of using propane is it’s more energy efficient than natural gas by volume. It’s one of the few non toxic petroleum based products so is considered to be more environmentally friendly.

The downside of course is the large propane cylinder that needs to be installed and kept filled to run the pool heater. If you don’t have natural gas and propane isn’t not too appealing then there are alternatives to consider like a heat pump.

Gas Heater or Heat Pump ?

Heat pumps cost more to buy but less to run than a gas swimming pool heater. They’re the most energy efficient, most suitable for temperate winter climates. They draw in warmth from the outside air then multiply the heat before transferring it to the pool water. 

To operate effectively, the ambient air outside needs to be 45º or higher. The lower the outside temperature the longer the pump needs to run and the larger the electricity bill.

That said they are still a hugely popular method of warming the pool. They’re quite a compelling choice for owners of large capacity above ground pools who want to extend their swimming season but don’t expect to use the pool year round.

No natural gas? and don’t fancy propane, then a heat pump might just be the answer.

What’s The Most Efficient Pool Heater ?

Everyone’s looking for the most energy efficient pool heater.  Gas or electric they’ll both heat your pool but by using very different methods. One uses natural gas or propane and the other uses air. That’s right a heat pump creates heat from fresh air, and just a little electricity of course.

Last time I checked fresh air was free, not subject to market fluctuations and tax. ( Of course that could change at any time if they find a way to tax it !! )

The price of natural gas, well that gets kicked about all over the place.

Heat Pump PROs and CONs?

Gas Heater PROs and CONs?

CALCULATE POOL HEATER SIZE

Finding the best pool heater size for your installation is pretty easily done, nothing too complicated here.

It’s the same for gas heaters and heat pumps. You just need to assemble a few facts and and decide if you want to use your pool year round or simply raise the temperature to start the summer pool season early and finish it late. 

Once you’ve got that clear the rest is straightforward.

That’s all we need to know. We’ll just put these numbers into this simple formula that will give us the output in BTUs we need from our heater.

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Required Heater Size in BTUs/hour =  Pool Surface Area x Temperature Rise x 12

So if we have a 30ft x 15ft pool and we need to raise the temperature 25º our formula would look like this.

450 (Pool Surface Area) x 25 (Temperature Rise) x 12 = 135,000 BTUs

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Easy enough!! No rocket science here. So for the example installation we need a heater with at least a 135,000 BTU output. 

In this case the best pool heater fit would need an absolute minimum 200,000 BTU , let’s find out why….

BUYING THE CORRECT POOL HEATER

The calculation we’ve just made is just a mathematical solution.  It  doesn’t take into account the pool heaters efficiency.

For example a  200,000 BTU rated heater with an 80% efficiency rating will deliver just 160,000 BTUs to the pool.  In terms we all understand that means that for every $100.00 you spend on gas just $80.00 worth gets to your pool. The rest, well it just goes up in smoke!

Whoops we’ve slipped into the real world. 

Apart from efficiency we also need to choose a pool heater size that can do the job at a stroll not in an 18 hour flat out sprint.

The more underpowered a heater is the longer and harder it has to work to keep up with and replace the heat loss from the pool.

In our calculated installation above if we just bought a 150,000 BTU heater it would need to run pretty much flat out 24/7 during the colder season to maintain temperature.

Without getting too deep into the science of heat and heat loss let’s just use a little logic here.

If your swimming pool heater is having to run at its limit day in and day out it’s going to need servicing and expensive parts replaced sooner than one thats easily achieving the required heat in a few hours a day.

The difference in price between heater sizes is often surprisingly little and we always recommend investing in at least 1.5 times the calculated BTU requirement.

GLOSSARY OF POOL HEATER TERMS

AHRI

Air-conditioning, Heating and Refrigeration Institute. The pool heat pump industry uses much of the same technology as your domestic air-conditioning unit so many manufacturers seek the AHRI seal of approval.

ASME

ASME is an abbreviation for the American Society of Mechanical Engineers. The best commercial gas pool heaters are manufactured according to ASME standards. As you can expect they use high quality durable build materials.They generally have a more advanced control system as well.

C.O.P.E.

C.O.P. is short for Coefficient Of Performance. It’s an efficiency measurement for pool heat pumps and heaters. It sound complicated and technical but it’s just a simple calculation. BTU Output divided by BTU Input = C.O.P.

Low NOx

NOx is just a shortened Nitrogen Oxide. Southern California and Texas require that both home and commercial swimming pool heaters meet the SCAQMD ( Yikes !! another acronym, it means South Coast Air Quality Management District ) low NOx emission standard.

Low NOx ensures gas pool heaters have very low levels of Nitrogen Oxide emissions. Generally they’re recognised as the best pool heater set ups and little more expensive, but are more efficient so the owner should notice lower gas bills.

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