Review Guide − Best 400,000 BTU Pool Heater / NG + Propane

Hint: The AVIA from Raypak is my top pick. It represents a brand committed to creating the best 400,000 BTU pool heaters for the modern age. It’s just the beginning of the pool industry evolving, but I appreciate what the Raypak engineers are doing, and it puts a spotlight on every brand that are still making pool heaters like it’s 1986 — which happens to be most of them.

Back in 2020 I’m sure a lot of us wondered if we’d ever make it to 2023, and here we are. We made it! The world is slowly going back to normal and now we’re looking to find a fast-heating and energy efficient, 400,000 BTU pool heater. Why? So we can enjoy our swimming pool all year round! Life is starting to feel like the good old days again, finally.

Luckily, we have some great options in either Natural Gas or Propane. The Hayward W3H400FDN (cupronickel) has been a consistent performer over the years, but is it in the category of best 400,000 BTU pool heater? I don’t really know anymore as we begin 2023. It’s good, but is it great?

Buying Hayward Pool Equipment Online

Personally, I find it disappointing and I suspect their sales have gone down because of this decision. A lot of people prefer to shop online so if consumers can’t find a brand like Hayward when shopping, the customer will simply purchase another brand. This is my opinion. I don’ have any data to back this up.

The Hayward W3H400FDP model is one of the most popular pool heaters available online. Back in 2019, Hayward decided to remove over 800 products from online sales. Their rationale was that certain products needed direct customer support, and felt that customers were not getting the help they needed. Basically, they now only sell a small percentage online (around 150) and those products are the ones that require less support because they’re easier to install and maintain. In other words, Hayward offers a small number of products online, and are preventing online retailers from selling all the rest.

Why Pool Companies are Slow to Change?

What’s the best pool heater brand? Raypak, Pentair, Hayward, Jandy? Do you have a preference or are you so fed up with your last pool heater brand that you’re ready to try something new? It’s no secret that pool heaters spark a lot of debate among customers. It’s not uncommon for customers to get so angry with their heater brand that it causes them to swing into the arms of a different brand in an instant.

I’ve read the stories, I know the contentious topics. A 400,000 BTU pool heater is expensive so when people find their heater breaking down after a couple years and then they’re told the warranty is over, the anger settles in fast. I don’t blame customers. There are major problems with the pool industry. They’re behind the times and they’ve been slow to adapt to the expectations of consumers. I’m going to be honest here, and send this message to any brand that might stumble upon this.

Major brands are vulnerable for a major disruption, if they don’t change a few things about their products and warranties. If they believe in the quality of their heaters then why wouldn’t they give customers a 5 year warranty? If I pay a certified pool technician to install a pool heater, then why wouldn’t I get a 5 year warranty? The brands that give a long warranty reveal how much they believe in their products, but in the pool industry this type of confidence and support are non-existent. Why? I’m telling you now, if customers aren’t supported with better warranties, better products, and real support, this market will be disrupted by a new brand.

Have you Considered a Pool Heat Pump?

We discuss heat pumps later in the article but if you have a swimming pool under 37,000 gallons and you live in a warm region of the country then you are a good candidate for a heat pump. We explain the good and bad of using a heat pump vs a gas heater after the photo of the Dr. Infrared Heater.

I want to dispel a myth about heat pumps that seems to be circulating in the zeitgeist. While it’s true that heat pump pool heaters are highly efficient and cost-effective, they were never designed or intended to provide instant or fast heating. Rather, they are engineered to maintain a constant water temperature, giving you a comfortable swimming environment throughout the season, day-in and day-out. Overall, heat pump pool heaters are a great option for those looking to minimize their energy costs while enjoying a comfortable and consistent water temperature in their pool.

Advantages of Heat Pumps:

Disadvantages of Heat Pumps:

Good Design & Pool Heaters: Does it Matter?

Hayward is a well-established brand with a long history of satisfied customers, but there are other reputable brands that make reliable pool heaters. Typically, people have their favorite pool equipment brand, but if you’re looking to replace an old heater, or you realized you need an upgrade, I think now is a good time to look at what other brands have to offer so you can make the right decision. I’ve noticed some interesting changes to the pool industry over the past couple of years and I you might find it useful to know where things are heading so you can avoid buying a pool heater that will obsolete in the near future.

In all honesty, most pool heaters are unattractive large cubes. I never understood why the big brands create such uninspired models, even though we live in a society where a lot more people seem to value good looking products, you can thank Apple for that. Humans are naturally drawn to beauty and repelled by ugliness. Finally, good design is propagating into pool heaters, coupled with intelligent Wi-Fi systems making them far easier to use and control.

Case in point is from Raypak − the new AVIA series, which you’ll see reviewed and discussed later in the article; and specifically, the 404K BTU model (018033) is our top recommendation in 2023. We also recommend two other Raypak pool heaters for you to consider. Either way, you have some great options.

Have your Pool Heater Professionally Installed

Here’s an important question to answer : Should you buy a pool heater online? It’s always cheaper if you buy the pool heater yourself. How do you think pool service companies make money? They always mark-up the pool heater when you buy from them, which costs you more money in the end. I’ll talk about this in detail as well, but my one piece of advice that you should take to heart is to make sure you have your pool heater professionally installed. Many people fail to invest in a proper installation, then complain when it fails them or doesn’t work properly. Don’t cheap out with pool heaters. Do it right and hire a certified pool technician.

Besides risking screwing up the installation and accidentally blowing up your back yard due to the error you end up making, which creates a slow gas leak, leading to a massive explosion at 3am the night of the install. Yes, besides the possibility that you cause a major explosion to happen, getting a certified pool technician to install the heater means you’ll get the warranty. If you install it yourself, you do NOT get thew warranty. You can file this under the “Good to know” section. More on this later.

Editors’ Picks : Best 400,000 BTU Pool Heaters

Most of these pool heaters are available in Natural Gas & Propane

Is Raypak the Best Pool Heater Brand?

Personally, yes, they have my vote for top rated brand and most advanced pool heaters.

Raypak is the brand that certified pool technicians like to install for their customers because they know they’re bulletproof pool heaters. I have read this very sentiment consistently when browsing online pool forums, where industry professionals hangout to share advice and get advice from their contemporaries. Raypak would be my top recommendation for gas pool heaters in 2023. They’re a brand committed to developing the most advanced pool equipment in the world. I have been frustrated at the level of stagnation in big brands like Hayward and Pentair. They’re pool heaters, pumps, filters, etc., are stuck in the 70’s.

I never understood this mentality. There’s so much room for an innovative brand to take market share and right now, I feel that Raypak is the brand leading the industry with nicer looking pool heaters, as you’ll find in the AVIA series. I don’t know if pool owners care or not, but based on the feedback I hear from customers looking to buy their next pool heaters, it’s easy to spot the pattern of frustrated pool owners unsure where to spend their money. This industry needs innovation. The AVIA pool heater is heavily featured in this buying guide because I personally love the series, and I have a lot of respect for the engineers at Raypak who are consciously fostering creativity and change in their designs.

Hopefully, other big brands will introduce new innovations that will spark other brands. This is how innovation is supposed to work, it hasn’t up until recently.

VIDEO: Hayward Pool Heater Installation

Best Commercial 400K BTU Pool Heater —

Raypak ASME Digital Pool Heater / 399,000 BTU — Model: C-R406A-EN-C (009271) / Natural Gas

Model: Raypak 009271 Digital ASME 399,000 BTU, Natural Gas Commercial Pool Heater with Cast Iron Headers, 0-2,000′ Elevation, B-R406A-EN-C #50

FEATURES /

OVERVIEW —

As the temperature rises, so does the need to keep cool. And if you’re lucky enough to have a pool in your backyard, you know that there’s nothing quite like a refreshing dip to beat the heat. But to enjoy your pool to the maximum, all-year-round, requires a reliable fast-heating pool heater like the Raypak 009271 ASME (American Society of Mechanical Engineers).

Overall, when you look at all of the features, specs and customer sentiment, you’ll quickly realize that the Raypak 009271 is an excellent buy for homeowners or for use to heat small public swimming pools. This natural gas heater has a power output of 399,000 BTU. It has all of the bells and whistles you’d expect, and more, like the standard electronic ignition system.

ASME is the Difference

What sets this pool heater apart from its residential counterpart is its ASME certification, which ensures that the unit is manufactured to meet the rigorous safety and quality standards set by the American Society of Mechanical Engineers. Typically, ASME heaters are used on commercial swimming pools because they’re used day in and day out, under the most extreme conditions.

It’s about $700 more than the standard residential model, Raypak 014941, which has a cupronickel heat exchanger and it’s NOT ASME certified. If you want the most durable 400K BTU pool heater then you’ll want the ASME, otherwise, stick with the standard homeowner 014941 and call it a day.

Here’s an example of what allows the Raypak heater to be certified.

At Raypak, all materials used in the production of an ASME Heat Exchanger undergo strict inspection and certification by a State Inspector to ensure compliance with ASME standards. The materials include copper finned tubing, tube sheets, and stud bolts, which are held for inspection by the inspector.

On average, the inspector visits the Raypak facility four times a week and carefully reviews all the materials and data reports to verify compliance with ASME standards. After passing the inspection, the heat exchange assemblies are properly tested by pressurizing with water up to 260psig (pounds per square inch gauge). In the last stage, the exchanger is thoroughly evaluated by the State Inspector to confirm everything has been done correctly, and that it meets the requirements. If everything goes well, the inspector signs the official report to confirm it has passed. You can be certain that an ASME pool heater meets all industry compliance standards.

Perhaps you’re not aware of this, but you might want to consider the ASME if you live near the ocean or any body of saltwater, as the more resilient materials will endure and resist corrosion better than the residential model. Both models have the proprietary ProTek Shield module, which has been designed to absorb corrosive-inducing chemicals. It basically attracts these substances and prevents them from entering the heater itself. It’s a clear window so if you see it corroding inside of it, then you know it’s working as it should.

The cabinet is corrosion-resistant, made from galvanized metal and its stainless steel tube sheets offer extra protection against harsh and corrosive elements. Additionally, the ASME model is required in some states for commercial use and offers a longer warranty.

VIDEO: A Close Look at this Raypak Digital Pool Heater Series

I know some homeowners want to install the pool heater themselves but it’s a bad idea when you consider you’ll void the warranty if it isn’t installed by a certified pool technician.  It’s not worth the risk, especially because it has gas connections and pipes. One small error and the consequences might be horrific. I don’t know about you, but the thought of a leaky gas pipe in my backyard would prevent me from sleeping at night. Unless you are a pool technician, just pay the extra money and do it right.

The cabinet is coated with a non-corrosive PolyTuf textured powder coating that’s more durable than traditional solvent-borne and waterborne-coated metal cabinets. The cabinet also goes through a 7-stage wash process during manufacturing to ensure a perfect bond between the paint and the galvanized metal underneath. This gives it excellent protection from chemicals and extreme weather, and more importantly, it won’t rust or corrode.

Having said that, you should check the coating on a regular basis. If you notice any deep cuts to the metal, you need to use a similar material and fill in the crack to stop rust from forming. Often this is how pool heaters begin to corrode, just one small scratch and slowly, from the inside out.

The design aesthetic and functionality is categorized as a “pagoda design,” with the benefit of being able to function normally even during high wind speeds and downdrafts. It’s also designed to prevent foreign objects from getting into the heater, such as leaves, pine cones and other surround debris. The last thing you want is something flammable entering the heater as this quickly becomes a fire hazard.

Having said that, you should check the coating on a regular basis. If you notice any deep cuts to the metal, you need to use a similar material and fill in the crack to stop rust from forming. Often this is how pool heaters begin to corrode, just one small scratch and slowly, from the inside out.

Quality Components Throughout

The Raypak 009271 ASME also has digital controls that require external power and generate a pilot only when there is a call for heat, saving energy and allowing for easy temperature control. The All-Copper-Fin-Tube Heat Exchanger is another feature that makes this more robust than the cupronickel model. Copper is more durable than cupronickel. The fin tubes are made from a single piece of extruded copper, once again, the reason is optimal efficiency. Raypak engineers have developed many unique components and systems that are used throughout the Raypak line of heaters.

You also get cast-iron headers for the best durability, with porcelainized waterways to make it more efficient. The reason why the ASME is so much more long-lasting and resilient is because of the quality of the materials. It’s that simple. You get: Cast Iron, Bronze, and Copper.

The Raypak 009271 is designed to give you flexibility when it comes to the installation.   It comes with a set of 2″ slip-fit CPVC water connections, making installation secure and effortless. And with a high flow rate of up to 125 GPM, an automatic bypass built into the header, and a burner tray built to last with stainless steel burners and aluminized metal used in heat-sensitive areas, this pool heater is capable of handling even the most demanding pool setups.

When it comes to fuel efficiency, the Raypak 009271 ASME consistently achieves the highest efficiency ratings and exceeds all federal and state standards. It is available for both natural gas and propane, making it a versatile option for any pool or spa.

If you go and read customer reviews you’ll notice a consistent theme of happy customers. This is one of the best 400,000 BTU pool heaters for the money and their newest AVIA series is even better in terms of features and technology, which I review a little later in this guide.

If you buy a Raypak heater, make sure you register for your 2-year extended warranty on their website. Basically, have it installed by a certified pool technician then send Raypak proof the install was done correctly, and you’ll get your full warranty.

What do Customers Think?

Customers seem to be generally satisfied with the Raypak (009271) ASME Digital Pool and Spa heater. Many customers have noted the excellent quality of the unit, with many customers stating the heater surpassed their expectations in terms of quality and construction. Some customers love the digital display and find it easy to use. Some customers have experienced issues with the rollout switch being too sensitive, but this does not seem to be a widespread issue. A few customers mentioned some difficulties with installation, such as unclear wiring instructions and tight access to headers, but these frustrations were outweighed by the overall performance and heating capabilities of the unit. Some customers also noted the cost being a little higher, but worth the extra expense for the improved performance.

VIDEO: See A Proper Raypak NG Installation (hire a certified technician)

Raypak AVIA 018033 / Natural Gas

Best New 400,000 BTU Pool Heater / Released in 2021

FEATURES:

OVERVIEW / AVIA 018033

Looking for an advanced pool heater that’s equipped with cutting-edge technology and a sleek design? The Raypak Avia 018033 is the one to beat. This pool heater integrates Wi-Fi and smart connections for real-time service alerts and control from anywhere. It also has built-in smart pool control automation, which allows you to automate and manage your pool temperature, and smart scheduling that ensures your pool is always ready when you need it. The Avia even learns the size of your pool and calculates the necessary heating time to reach the desired temperature.

But the technology doesn’t stop there. The Avia series also includes the Smart Ecosystem Manager, which enables you to manage your heater, pump, or water feature and scheduling. And with the Raymote Mobile App, you have temperature and heater control at your fingertips. Real-time updates notify you of any service or maintenance needs, so your heater and pool are always ready to be used.

VIDEO: Overview of the Technology Used in the Raypak AVIA

The Raypak Avia 018033, is one of the best 400,000 BTU pool heater in 2023, and the most technologically advanced. If you prefer your devices and tools to be intelligent, you’ll appreciate how it makes your life easier. I also like that it’s been designed with aesthetics in mind. Pool heaters are generally ugly, let’s be honest, but the AVIA series is the first time I noticed the style of a heater, and it was refreshing.

Its compact size and straight tube heat exchanger design make it the most serviceable pool heater on the market. It’s one of the most streamlined gas pool heater on the market, at under 140 lbs. and small enough to fit on a 2-feet x 2-feet mounting pad. Installation is relatively straightforward, with little details such as the 360° rotating top cover, giving you more options as to where you’re going to place it. The removable top is a nice touch, and easy to take off. It’s designed to securely hang down on the side of the heater, giving you full access, for maintenance or repair.

Energy Efficiency / New California Laws for 2030

It has an 84% efficiency rating, which slightly higher than the 82% minimum requirement set by the U.S. Department of Energy, but it’s far away from the 93% efficiency of the Pentair UltraTemp ETi Hybrid. The Avia 018033 is low NOx certified, meaning that it produces fewer emissions than other pool heaters.

If you live in California, you might be interested in the fact that new gas heaters, furnaces and water heaters will be banned by 2030. The reason is to reduce emissions and to keep up with the latest ozone (O₃) standards of 0.070 parts per million (ppm) set in 2015 by the Environmental Protection Agency (EPA). This was unanimously voted on in late 2022 by California Air Resources Board (CARB). Maybe you should stock up on natural gas pool heaters because you won’t be able to buy one after 2030.

I expect this will spread to other states and countries. The goal is to get everyone to buy an electric pool heater, but the electrical grid in California is already stressed. It seems foolish to put even more pressure on it, which will likely increase to frequent blackouts. Either way, I don’t make the laws, I just report them.

VIDEO: Choosing the Best Pool Heater for Where You Live

Durability

It’s also designed to last for many years, it includes Raypak’s proprietary ProTek Shield technology engineered to protect the heat exchanger. It’s basically a module connected to the header and it absorbs any corrosive materials, elements, chemicals, etc. It functions somewhat like a filter, as it removes corrosive particles to prevent corrosion within the heater itself. You know the ProTek shield is functioning properly when you see corrosion inside the module. It’s an interesting idea and it’s a patent-pending technology developed for the AVIA series of pool heaters.

When you look at past Raypak pool heaters, most owners report that their heaters have lasted for 15 to 18 years. The Avia 018033, should give you at least 10 years of performance and hopefully much more. As with all new pool heater models, it’s impossible to know how it will hold up over time because this is a new design. Having said that, it does use time tested components they’ve used in older models, so it’s reasonable to expect a durable long-lasting design, on par with past designs.

When it comes to customer support, Raypak and Rheem have a reputation for building reliable and durable pool heaters. The Avia comes with a warranty that covers the unit for two years and the heat exchanger for 10 years. It’s important to note that you must hire a certified pool technician for installation, or you will lose your warranty.

AVIA Product Development Began in 2018

The Raypak Avia pool heater has been making waves in the pool industry since its introduction in December 2021. But did you know that Raypak has been working on this heater since 2018? According to Satya Gullapalli, Raypak’s senior project engineer who led work on the AVIA, the company recognized the trend towards smaller pools and the desire for automation features within the heater itself. This led to the creation of a pool/spa heater that incorporates a built-in, advanced Wi-Fi–enabled control system, allowing users to access and operate the heater remotely with the Raymote app.

But what’s even more impressive is that the development process for the AVIA included input from customers at every step, looking at aesthetics, functionality, and ease of use. Raypak conducted extensive field testing to ensure the reliability of the AVIA, which presented a significant obstacle during the pandemic. Despite the challenges, Raypak launched the AVIA in December 2021 and the feedback from customers has been very encouraging.

The AVIA’s compact size and user-friendly controls have been big selling points for customers, as well as its ability to heat a pool quickly, which happens to be the most important feature customers care about when buying a pool heater.

Tom Brockett, one of the owners of Aquaman Pool Service, Inc., installed his company’s first AVIA heater in December 2020, a pre-production prototype provided by Raypak for testing in the field. Brockett was impressed with the AVIA’s higher efficiency, Wi-Fi monitoring capabilities, and newer technology. After installing four AVIA heaters in both year-round and seasonal pools, Brockett’s assessment of the AVIA is very positive, with the Wi-Fi monitoring capabilities being his favorite feature.

Do We Need Smart Pool Heaters?

While the integration of intelligent technology in the Raypak Avia 018033 pool heater may be a significant selling point for some consumers, it is possible that others may find it overwhelming or too complicated to use. In a world where technology is becoming more ubiquitous in our daily lives, it is important to consider the potential impact of these advancements.

While the convenience and accessibility of controlling your pool heater from your phone may seem like a benefit, it’s also important to consider the potential downsides. For example, what happens if the app malfunctions or your phone dies? Are we becoming too reliant on technology to manage even the most basic aspects of our lives? And what about the people who prefer the simplicity of a manual control panel?

It’s also worth noting that the Raypak Avia 018033 does come with a digital control panel, so customers do have the option to use either that or the Raymote app to manage their pool heater. This is a great example of how technology can be integrated into products without completely eliminating traditional methods of control.

In the end, it’s up to the consumer to decide whether the integration of intelligent technology in their pool heater is a good thing or not. But it’s important to remember that as technology continues to evolve and become more advanced, we should always consider the potential impact it may have on our daily lives and how we interact with the world around us.

Rheem is an American manufacturing company that produces a variety of heating, cooling, and water heating products for residential and commercial customers. The company was founded in 1925 and is based in Atlanta, Georgia.

Rheem acquired Raypak in 1985 which allowed the company to expand its product offerings into the pool and spa heating market. Raypak was already well-established in the pool heating industry, known for its reliable and efficient products, and the acquisition provided Rheem with a strong foothold in this market. Since the acquisition, Raypak has continued to operate as a separate brand within the Rheem company, focused solely on producing pool and spa heaters.

Should you buy a pool heater with a cupro-nickel heat exchanger?

Most pool heaters come with either a copper heat exchanger or a slightly more expensive cupronickel heat exchanger (also known as : copper-nickel). Cupronickel is a mixture of copper and nickel, as well as strengthening metals such as iron and manganese. This blend of chemical elements, with at least one metal, is called an alloy. Cupro-nickel and has superior resistance to salt water and water with higher acidity.

If you have a salt water pool then yes, you should definitely buy a cupronickel pool heater as it will last you many years longer than a regular copper heat-exchanger. The difference in price is only about $200 to $300 so it’s a wise investment considering how expensive pool heaters are. If you have a traditional chlorine pool you don’t need a cupronickel pool heater if you always maintain the proper PH and the water is rarely too acidic. Most pool homeowners aren’t perfect with maintaining these high standards, so you need to be honest with yourself. Is worth the extra cost to you? Personally, I feel it’s wise to spend the few extra hundred dollars to get a a more durable pool heater.

For example, here are the two different Raypak 406K BTU pool heaters. Be sure to buy the right one :

You’ve been warned. These are expensive and complex machines. If you overlook one thing it can cause your system to fail and ruin the heater itself. Don’t risk doing it yourself. Just hire a professional to install it.

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Propane vs Natural Gas: Does it Matter?

The type of gas you use has an impact on your costs, the environment, and even the effectiveness of your heating system.

Heating a swimming pool is a significant investment, and choosing the right fuel source for your pool heater is an important decision. The two most common types of fuel sources for pool heaters are natural gas and propane. Both have their pros and cons, and choosing the right one depends on your needs and preferences.

One of the significant differences between natural gas and propane is their chemical composition. Natural gas is mostly composed of methane, while propane is a hydrocarbon gas that is a by-product of the petroleum refining process. The difference in composition can have an impact on the efficiency and emissions of the pool heater.

VIDEO: Pool Heater Setup with Propane Tank / Hayward W3H250FDP

When it comes to efficiency, propane heaters tend to be more efficient than natural gas because of their higher energy density. One cubic foot of natural gas generates around 1,000 BTUs of heat, while one cubic foot of propane generates around 2,500 BTUs of heat. Generally, propane heaters require less energy to operate, and they can often be more cost-effective in the long run, depending on the price of fuel in your area.

Another important consideration when choosing a fuel source for your pool heater is emissions. Both natural gas and propane produce carbon dioxide (CO2) when burned, but propane generally produces less CO2 per unit volume than natural gas. Additionally, propane produces significantly fewer nitrogen oxide (NOx) emissions than natural gas, which can be harmful to the environment and human health.

To calculate the size of the propane tank needed for your 400,000 BTU propane gas heater and a 20,000-gallon pool, you will need to know the propane usage rate of your heater, which should be listed in the owner’s manual or on the manufacturer’s website. A 500-gallon propane tank, which holds around 400 gallons of propane due to the 80% fill limit, would last approximately 4-5 days if your heater is running constantly.

Propane tanks are only filled to 80% of their rated capacity because propane expands when it’s heated. In fact, propane expands about 17x more than water when heated, so the expansion is significant. If you have a 500-gallon tank it should never be filled with more than 400 gallons of propane.  

One of the great qualities of propane is that you can store it for about 10 years without any degradation. We cover generators on this site as well and propane is superior to gasoline because of how easy it is to store. Also, the fact you can easily store propane in a tank means you can easily move it around. This is less important for a swimming pool, but for generators, this is a critical advantage.

The cost of having propane delivered to your home can vary depending on your location and the provider, but on average, it can range from $2 to $4 per gallon. The cost to fill a 500-gallon propane tank can range from $800 to $2,000, depending on the current price of propane in your area. For example, today, the price of propane in New York is $3.5 per gallon, so a 500-gallon tank at 80% capacity would cost $1400 for 400 gallons.

We’re living in a world where gas is slowly being replaced by electric systems so I imagine that one day a gas pool heater will be a relic of the past. It won’t be for a couple more decades but the trend is already starting as California is banning gas heaters in 2030; 7 years from now. In the meantime, we still need gas as it’s an excellent energy source. I’m not worried about the future because I live in the present. My advice is for you to enjoy your swimming pool and warm it to your ideal temperature.

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Your 400K Pool Heater Options for 2024 —

Nobody wants to swim in a cold pool — unless it’s 100°F. If you own a pool, you need a heater. A 400,000 btu pool heater is ideal for pools over 40,000 gallons. But you should also know that it’s always better to buy a larger pool heater so you’re not running your heater at 100% all the time. This makes it run quieter, last longer and because of larger size, it will heat your pool quicker.

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Quality Brands, History Matters

If you’re curious about the reputation about these two brands — Raypak was founded in 1947 by Al Whittel. They’ve been in business over 70 years. For comparison, Hayward has been in business over 80 years. Basically, these are two very reputable brands with a rich history of manufacturing to the highest standards.

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Overview : 400K Pool Heaters

Raypak R406A / Best 399,000 BTU Pool Heater / Natural Gas

Features :

• ProTek Shield is a cutting-edge module that protects the heat exchanger and extends the life of your Raypak Digital Gas Pool and Spa Heater.  
• Excellent for use in chlorinated and salt water pools
• Engineered to take the brunt of the corrosion that naturally occurs over time (erosion of the ProTek Shield means it’s working!)
• Utilizes breakthrough patent pending technology
• Compact design  Easy to replace, saving you time and money
• PolyTuf Textured Powder Coating
  Wind-Resistant Design
• Microprocessor Controlled Thermostat
• Low-profile design, corrosion resistant cabinet made of galvanized metal, copper fin tube heat exchanger, and a bevy of advanced-engineered materials

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I’m sure you know that pool heaters are not all made to the same standards. You do have a few fantastic options available, so let’s take a look at them before discussing heaters in more detail:

NOTE from EDITOR : Some of these heaters may not be available at the moment, as I’ve noticed that fewer pool heaters are being sold online nowadays. I believe it has to do with the warranty. Retailers don’t want to deal with pool heater returns. These are big and expensive, making it costly to handle returns.

Make sure that you are getting a full warranty when purchasing online. I think that most consumers aren’t aware that the warranty may be void if you buy the heater online and you install it yourself. To be safe, always have it installed by a certified technician so there’s never any doubt as to the quality of the installation and blame can never be directed at you.

In addition, ensure that you get the full warranty. If not, you’re better off buying locally and having it installed by the company you buy it from. If anything goes wrong they can simply drive over and fix it. Think carefully before buying a pool heater online.

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*Note : All of these are 400,000 BTU pool heaters.

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Review: Hayward W3H400FDN — Universal H-Series

400,000 BTU Pool Heater — Natural Gas

✓  Also available in propane : Hayward H400FDP (400,000 propane model)

Features:

• Standard cupro-nickel heat exchanger
• Excellent salt water and chemical corrosion resistance
• Exclusive “Totally Managed” cupro nickel heat exchanger water flow
• Same water velocity through all tubes for faster heating
• Patented header by-pass design
• Up to 18 percent savings by reducing pump run-time
• 2″ x 2 1/2″ CPVC union plumbing connections
• Common union for installation or service, adapts to larger plumbing recommended for greater
• efficiencies
• Low NOx emissions – meets clean air quality standards

✓ View or download the MANUAL and the BROCHURE for the Hayward H400FDN.

Overview

Hayward Industries, Inc. has been around for a very long time.  It’s an American-based manufacturer of residential and commercial swimming pool equipment. They were founded in 1925 and began their journey as a  manufacturer of wooden buoys and fishing nets.

The Hayward Universal H-Series pool heater is a popular model when people buy online. It’s available in a natural gas or propane model:

• Natural Gas = W3H400FDN model  
• Propane = W3H400FDP model

The Hayward Universal H-Series has been on the market since 2008 and has been revised and updated over the years. This is not uncommon with pool heaters and other heavy-duty power equipment like portable generators. The W3H400FDN is designed to heat large pools up to 40,000 gallons.

It’s generally a reliable heater but there are customers who had the heater die on them after one or two years. There are always negative experiences with every type of product you can buy from any company. Even the Apple iPhone malfunctions or arrives dead. It’s important to look at the average when evaluating a pool heater, and on average this 400,000 BTU heater is rated at about 4 out of 5 stars. That would be a fair assessment.

VIDEO Review – A Closer Look at the Hayward H-Series Pool Heater (NG / 400K BTU)

https://youtu.be/vsKaUgGCqxY

This is also why I always put more significance on reviews based on a large number of customers because if you make your decision based on what one person thinks or says, then there’s a good chance you’ll be deceived. One opinion is not representative of the truth about a product. The most accurate feedback you can find when shopping for a product is looking at a diverse range of opinions coupled with a singular person who can help you put it into context while adding their own personal feedback. I am just one voice, but I always use customer reviews to get an accurate picture of the quality of the product. It’s quite simple.

Back to the heater. Sorry, I tend to make U-turns occasionally

The materials used are of high quality and durable. It’s designed to withstand harsh weather conditions and long-term usage. The heat exchanger is made of cupronickel, making it more resistant to corrosion while allowing heat to be transferred efficiently. Hayward has been around for a long time, which has its advantages but at the same time I have found that Hayward have been slow to develop new pool heaters. I hate to say it, but I feel that their line of pool products have begun to look dated. In fact, I felt this way 5 years ago, but even more so now, in 2023.

The truth is, pool heaters are not very complicated. They’re big and bulky but they’re not complicated. Technology, in general, has been evolving at a rapid pace alongside technology with the user experience increasing in importance, with far more people being conscious of the importance of usability and UX —  the interface by which humans interact. The control panel for the W3H400FDN is clunky and dated. The entire look of the heater itself seems stuck in the 90s but this is common for a lot of pool heater companies. I find it frustrating this might not be an issue for a lot of people.

All that matters is how it functions, how efficient it is at heating your pool, and how reliable it is.

VIDEO – How to Wire Your Hayward Pool Heater (Natural Gas)

In terms of efficiency, the Hayward Universal H-Series is designed to be energy efficient and environmentally friendly. It is compliant with the California South Coast Air Quality Management District’s district low NOx emissions standards, which helps to reduce the heater’s impact on the environment.

The Hayward Universal H-Series comes with a limited warranty of two years, which covers parts and labor. An optional extended warranty of up to five years is available for purchase. Make sure you purchase this from an authorized dealer and then register it.

Despite my frustration with the overall usability and outdated aesthetics, this is still a reliable pool heater for homeowners.

What Customers Think and Say

When you look at what customers say, you’ll notice that Hayward  400,000 BTU Universal H-Series pool heater gets an average rating has received mixed reviews from customers. While some have praised its efficiency and reliability, others have experienced issues with its durability and warranty.

One customer noted that “it heats our pool quickly and efficiently,” while another stated that “it’s been a reliable and effective heater for our pool.” However, others have had negative experiences, with one commenting that “after just two years, the heater stopped working and the warranty didn’t cover the repair costs.”

Another customer mentioned that “the heater is quiet and easy to use,” while someone else highlighted its compatibility with different fuel sources, saying “the dual fuel system is a great feature for those who may need to switch from natural gas to propane.”

However, there were also complaints about the durability of the heater, with one customer saying “we’ve had to replace the heat exchanger twice in the past five years,” and another noting that “the unit corroded quickly and needed extensive repairs within a few years of use.”

Overall, it seems that the Hayward Universal H-Series pool heater has both its strengths and weaknesses. While it is praised for its efficiency and compatibility with different fuel sources, there have been issues with its durability and warranty. As with any product, it’s important to carefully consider all factors before making a purchase and to do proper research to ensure it meets your specific needs and expectations.

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Review: Pentair 460736 / 460737 — MasterTemp

400,000 BTU Pool Heater — Natural Gas and Propane

✓  Also available in propane : Pentair 460737 (Propane Model)

Features:

• Heats up fast, so no long waits before enjoying your pool or spa
• Best-in-class energy efficiency
• Hot surface ignition (no pilot light)
• Manual gas shutoff when service is required
• Eco-friendly MasterTemp is certified for low NOx emission and outperforms industry standards
• Rotating digital display allows for easy viewing
• Tough, rustproof exterior handles the heat and weathers the elements

Overview

One of the big features we’ve not looked at yet is noise. If you’re trying to swim multiple laps you don’t want any loud distractions in the background. Once you’ve switched the Pentair 460736 MasterTemp pool heater on you won’t even hear it unless you’re standing up close. The super-quiet operation ensures you can relax when you’re inside the swimming pool while staying toasty at the same time.

If you have any natural gas products in your home you’ll be aware of pilot lights, but they’re not very reliable. I’m sure you’ve pressed igniter buttons more than a couple of times in the past. The 460736 MasterTemp uses hot surface ignition to start everything up with the help of an electrical button. Once the surface is finally warm low voltage, high current electricity will ignite it.

460736 is the Natural Gas Model

The Pentair 460736 MasterTemp 400000 BTU pool heater measures in at 29.9 x 36.1 x 22.8 inches, so you won’t always be able to see it. A couple of features will help you out in this department. First of all, it can be elevated off the ground so it’s always in view. The user-friendly indicator lights will also let you monitor it without paying too much attention to it. You’ll know something is wrong when they flash.

It’s easy to say a pool heater has low NOx emissions, but it’s not just about buyers feeling good about helping the environment. There are low NOx regions around the country where emissions have to be under a certain amount. California is the standout state with the strictest rules. Don’t worry because you’ll be able to use your 460736 MasterTemp 4000000 BTU pool heater anywhere.ho

Buying Guide: Pool Heater Essentials

How A Gas Pool Heater Works

In a minute, we’re going to discuss why you’ll need a 400000 BTU pool heater. It’s probably a good idea to talk about how they work before moving onto anything more complicated. A pump will circulate the water around your swimming pool, which includes sending it through a filter to clean it effectively.

The water will then move into the heater. While the water is moving through the system your natural gas will be burning in the combustion engine of the heater. It will generate a lot of heat and warm any water passing through it. By the time it reaches your pool it will be sitting at a higher temperature than before.

Imagine cold water flowing down a hill in a straight line trying to reach a puddle at the bottom. If someone was standing with a blowtorch blasting the water as it flowed downhill the puddle would be warmer than the water at the top of the hill. It’s essentially the same thing except pool heaters are much more technologically-advanced.

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Heat Pumps and Buying the Right Size Pool Heater

What’s the right pool size for your pool size (in gallons)?

• 50,000 BTU:
  • Up to 10,000 gallons
• 100,000 BTU:
  • 10,000 to 15,000 gallons
• 150,000 BTU:
  • 15,000 to 20,000 gallons
• 200,000 BTU:
  • 20,000 to 25,000 gallons
• 250,000 BTU:
  • 25,000 to 30,000 gallons
• 300,000 BTU:
  • 30,000 to 35,000 gallons
• 350,000 BTU:
  • 35,000 to 40,000 gallons
• 400,000 BTU:
  • 40,000 to 45,000 gallons
• 450,000 BTU:
  • 45,000 to 50,000 gallons
• 500,000 BTU:
  • Over 50,000 gallons

It’s important to note that these ranges are estimates and can vary based on factors such as the climate, desired temperature, and pool usage.

When do heat pumps make sense for pool owners?

Heat pump pool heaters are a highly efficient and cost-effective way to maintain a constant water temperature. However, one of the most common misunderstandings about their operation is the energy consumption and heat output. Unlike traditional gas heaters, the electrical energy used to run the heat pump does not directly heat the water. Rather, the energy is used to power the unit’s compressor, fan, controls, and electronics, which together extract heat from the surrounding air.

In fact, the electrical input energy only accounts for a small portion of the total heat output. The vast majority of the BTUs produced by a heat pump pool heater come from the heat energy extracted from the air. This is due to the unique way that heat pumps work, utilizing the ambient air to extract and transfer heat to the water in the pool.

The efficiency of heat pump pool heaters is typically measured by the Coefficient of Performance (COP), which is a ratio of the heat output to the electrical energy input. Most heat pump pool heaters have a COP value between 4.0 to 6.0, which means that for every unit of energy used to power the unit, 4 to 6 units of heat are produced. This high level of efficiency not only reduces energy costs, but also minimizes environmental impact by reducing carbon emissions.

Heat pump pool heaters are a fantastic option for pool owners looking to maintain a comfortable water temperature while also reducting energy costs. Truth is, these units are not designed to provide fast or instant heating. They’re designed to maintain a constant water temperature, throughout the year or season.

Heating Capacity

The true heating capacity of a pool heater can be affected by a number of factors, including the outdoor temperature, wind conditions, pool size and shape, and the efficiency of the heater itself. To compensate for these variables, pool professionals use the “temperature rise” formula, which takes into account the desired pool temperature, the average air temperature, and the difference between the two.

The temperature rise formula is:

This formula is a useful tool for determining the temperature rise required to heat your pool to the desired temperature. In addition to the temperature rise formula, pool heater manufacturers often provide sizing guides that take into account factors such as wind speed, humidity, and even the amount of direct sunlight that the pool receives during the day. It’s important to consult the manufacturer’s sizing guide and follow their recommendations to ensure that you select the appropriate size pool heater for your specific pool and environmental conditions.

When it comes to choosing between gas pool heaters and heat pumps, there are a few things to consider. Gas pool heaters are more powerful and can heat your pool faster, but they’re far less energy efficient and require a constant supply of fuel. Heat pumps, on the other hand, are more energy efficient but they also take a lot longer to heat your pool, and you’re reliant on the outside air temperature to determine that speed.

Heat pumps work best in areas with moderate climates where the temperatures stay above freezing, and the humidity is not too high. The minimum temperature for a heat pump to work efficiently for pool heating is above 50°F but I recommend closer to 60 °F for a minimum. Above this temperature range heat pumps can actually warm your pool. Some of the best states for heat pumps include Florida, California, Texas, Arizona, Nevada, and Louisiana. These states have milder climates with a longer swimming season, making them ideal for heat pumps. However, heat pumps can work in other regions of the country as well, but they may need to be used in conjunction with other heating sources during colder months.

Gas or propane pool heaters, on the other hand, are suitable for any climate, as they can provide heat even in very cold temperatures. However, they are less energy-efficient than heat pumps, and their operating costs can be higher.

It’s important to note that heat pumps work best in warmer temperatures, typically above 50-55 degrees Fahrenheit. As the air temperature gets colder, the heat pump has to work harder to extract heat from the air, which can reduce its efficiency and effectiveness. Therefore, regions with warmer climates and longer swimming seasons are typically more suitable for heat pumps. In areas with colder climates, a heat pump will not be able to extract enough heat from the ambient air to warm up your pool. It’s as simple as that. If the air is cold, where does the heat come from? In this case, a gas or electric pool heater will be a better option.

The optimal humidity range for a heat pump is generally recommended to operate the unit in areas with a relative humidity of 80% or lower. This is because high humidity can lead to increased condensation on the heat pump’s evaporator coil. This reduces its efficiency and will likely cause damage over time. However, most heat pumps are designed to handle a wide range of humidity levels, and some brands integrate features like a built-in dehumidifier to help manage high humidity.

Check your manufacturers guidelines because every pool heater, heat pump, brand and series, will have its own recommendations. These points are generalities that may or may not apply to certain pool heaters.

General recommendations for the right heat pump power output for your pool size:

Common Pool Problems and Solutions

As somone who has owned many swimming pools, including growing up with one in our yard, I’ve seen firsthand the preventable issues that can cause a pool heater to break down prematurely. Regular maintenance is critical to prolong the life of your pool heater and prevent problems from occurring. Here are some solutions and prevention techniques to make your life better and hopefully prevent a disaster.

Filter

One of the most common preventable issues is related to the filter. Over time, the filter can become clogged with dirt and debris, causing the heater to work harder to heat the water, which can lead to a breakdown. To prevent this from happening, be sure to clean your filter regularly. How often you need to clean it will depend on how frequently the pool is used and the location of the pool. Typically, cleaning the filter every few months is sufficient, but if the pool is used more frequently or in a heavily trafficked area, you may need to clean it more often.

Thermostat

Another common problem is related to the thermostat. If the thermostat isn’t functioning correctly, it can cause the pool heater to work harder than it needs to, which can lead to a breakdown. It’s important to regularly test your thermostat to ensure that it’s working properly. A simple way to test your thermostat is to turn it up a few degrees and see if the heater responds by heating the water. If the water doesn’t get warmer, then there may be an issue with the thermostat that needs to be addressed.

Electrical

Electrical components can also be a common issue that pool owners face. The electrical components of a pool heater are complex, and if they’re not functioning properly, it can cause the entire system to break down. To prevent this from happening, it’s essential to have your electrical components checked regularly by a professional. This can help identify any issues before they become major problems.

If you don’t know anything about electrical maintenance then please don’t touch any wires. Just call a professional. It’s well worth the cost.

Gas Leaks

Gas leaks are another problem that pool owners may encounter. Gas leaks can be dangerous and pose a significant safety risk, so it’s important to check for gas leaks regularly. One way to do this is by turning off the gas supply valve, applying soapy water to the valve, and looking for bubbles. If bubbles appear, there is a gas leak that needs to be addressed immediately. Gas leaks can occur due to a faulty valve, loose connections, or a damaged gas line.

Bugs & Rodents

Bugs and rodents can also be a significant problem for pool heaters. Animals such as mice, squirrels, and other rodents can be attracted to pool heaters, which can cause severe damage to the system. To prevent bugs and animals from destroying your pool heater, it’s essential to take preventative measures. One common solution is to cover the pool heater when it’s not in use. Also, keeping the area around the pool heater clean and free of debris and clutter can help deter animals and insects.

Benefits of A 400,000 BTU Pool Heater

Those will a large pool will never regret buying a 400000 BTU pool heater. We’re going to discuss their main benefits, but first have a look at the table below, created by professionals. It shows what size of heater you’ll need depending on the water in your swimming pool and its total surface area.

Pool Heater Size / Gallons In Pool / Surface Area

• 100-200 BTU / 1,000-10,000 / Up to 300 sq ft
• 200-300 BTU / 10,000-20,000 / Up to 500 sq ft
• 300-400 BTU / 20,000-40,000 / Up to 800 sq ft
• 400 BTU / 40,000-80,000 / Up to 1200 sq ft

When you’re working out the size of your pool it’s always better to focus on the gallons of water inside it. The surface area can be a big help too, but it obviously doesn’t account for the depth of the water. If your swimming pool is a little deeper at one end it could add thousands of gallons onto the total.

Did you know there are 7.5 gallons of water in a cubic foot? Remember this number because it’s extremely important. If you want to work out how many gallons are in a constant depth (square or rectangular) pool you would use this equation:

Length x Width x Depth x 7.5 = Total Gallons

If you have a shallow end it’s also possible to use this equation to give you a rough estimate:

Length x Width x Average Depth x 7.5 = Total Gallons

Don’t worry if you have a more complicated pool. There are online calculators that will help you figure out the amount of water in your pool.

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Calculations Don’t Give You The Full Picture

A lot of people won’t have a swimming pool with more than 40,000 gallons of water inside it, so they might decide a 400000 BTU pool heater is too big. There are other things you’ll need to take into consideration too. They’ll offer you benefits a smaller pool heater could never give you even if your pool isn’t huge. Let’s take a quick look at them:

• Your Pool Will Heat Up A Lot Faster
• Minimal Price Difference
• More Energy Efficient
• Perfect For Heating Hot Tubs

Your Pool Will Heat Up A Lot Faster – The average gas heater will increase the temperature of a pool by a few degrees per hour. Obviously a 400000 BTU pool heater will work faster than a smaller one, which is good when you’re desperate to jump into the water.

Your swimming pool might have fewer gallons of water inside it, but you’ll wait a long time for it to heat up. If you’re ever on the fence about which model to buy always opt for a bigger one. It’s a decision you will never live to regret.

Minimal Price Difference – Have you looked at the price of pool heaters? Forget about the total cost because they’re worth it. I want you to examine the price difference between 400000 BTU pool heaters and smaller models.

You’re looking at a difference of roughly a few hundred dollars, which isn’t bad considering they’re worth thousands. Why would you try to save a little money when you could buy something a lot better without a noticeable difference in price?

More Energy Efficient – Gas heaters are excellent because you can decide on a temperature you like. The heater will do everything possible to keep it at your desired temperature every time you jump into the swimming pool.

Which model do you think will find this easier? A smaller model will have to work a lot harder than a 400000 BTU pool heater to maintain your preferred temperature. It means it will need to work harder, so it will burn through more energy over its lifetime.

Perfect For Heating Hot Tubs – I hope you have a hot tub attached to your swimming pool. Doing multiple laps to stay healthy is nice, but nothing beats relaxing in a tub. The only way you’ll enjoy them is when they’re nice and warm.

If you have a hot tub you’ll want a pool heater that will heat your tub up quickly and effortlessly. A 400000 BTU heater should warn your hot tub in around 15 minutes. If you own a smaller pool heater it will take longer until it hits your desired temperature.

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Getting The Most Out Of Your Gas Pool Heater

Once you’ve decided to spend a chunk of change on a gas pool heater you’ll want a couple of things. First of all, you’ll want it to last a very long time. If you don’t use it a lot you’ll get your wish. You’ll also want it to be more energy efficient, because you’ll spend a lot less money during the summer months.

It’s possible to accomplish these things by reducing the demands on your pool heater. A lot of swimming pool owners don’t even take them into consideration, but you can’t afford to ignore them. We’re going to look at the tricks you can use and why it will help you save lots of cash going forwards:

• Using A Good Pool Cover To Retain Heat
• Build A Fence To Stop Wind Getting In
• Use A Manual Thermostat To Test The Water
• Switch The Heater Off When You’re Done
• The Heater Installation And Maintenance

Using A Good Pool Cover To Retain Heat

A swimming pool is similar to the human body. It loses roughly 90 percent of its energy through the top of the pool. They say around 70 percent of heat is lost through evaporation, plus 20 percent is lost to the sky through radiation. The remaining 10 percent is lost through things like losing heat to the ground.

Think about that for a couple of minutes. It will add a huge amount of money onto your monthly bills, but the solution couldn’t be easier. All you need to do is put a cover over the top of your swimming pool when it’s not in use. Hopefully you’ll realize the time you will waste doing this is well worth it.

The pool cover you use doesn’t need to be anything special. There are bubble covers designed with thick grade materials and UV inhibitors, but to be honest any cover will do when you’re getting started. You can research all your options once you plug the hole in the bottom of your mug.

I’d like to give you a few examples of the costs it takes to heat a swimming pool per year when you try to do everything without (and with) a cover:

• New York $1448 ($208 with cover)
• Boston $1712 ($232 with cover)
• Los Angeles $1864 ($168 with cover)
• Seattle $1525 ($304 with cover)

Please Note: These figures are based on a pool heated to 78 degrees Fahrenheit. The swimming pool is 1,000 square-foot, uncovered 8 hours per day, and the gas heater is 80 percent efficient.

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*** Extra Pool Cover Benefits

At the moment, you must think pool covers are the greatest thing that’s ever been invented. They might not come close to the wheel, airplanes, or peanut butter, but they do have extra benefits too. I’d like to take a quick second to look at them to ensure you don’t go to bed tonight without ordering one.

You’ll Be Able To Conserve More Water – It’s not just heat that disappears into the atmosphere. 30-50 percent of the water from your pool will eventually disappear too, so you’ll need to keep topping it up on a constant basis. The world is running out of fresh water and they think it will cause mass devastation by 2050. Keeping a cover on your pool will help the planet.

You Can Start Using Less Chemicals – The chemicals you have in your pool will float into the sky too, which won’t be doing it any favors. It’s only going to speed up the destruction of our atmosphere. Using 35-60 percent extra chemicals will affect you negatively too. Not only will you need to pay for them, but you’ll need to store them in your garage.

It Won’t Take You Long To Clean The Pool – How long do you spend cleaning your pool on a weekly basis? Once you start using a pool cover those hours will drop considerably. If the leaves and other debris can’t fall inside they won’t need to be fished out. If you value your time it’s a fantastic investment.

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Build A Fence To Stop Wind Getting In

When you switch on the heater you’re not just trying to warm up a pool of water. You’ll be fighting against the elements at the same time. Cold winds will be doing their best to reduce the temperature of your water, which will increase the demands of your 400000 BTU pool heater.

In these situations, it’s tough but you’re not left completely helpless. You can begin battling against the wind. Don’t put too much effort into it because it’s not worth it. Just erect fences around your pool if you feel it’s too exposed. Do the work yourself and it won’t cost a lot of money.

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Use A Manual Thermostat To Test The Water

The reason we’ve mentioned 78 degrees Fahrenheit is because it’s the temperature lots of people set their pool heater too. It’s what the majority of the population deem comfortable. 82 degrees Fahrenheit is usually the maximum temperature they’ll set it to. There are no rules, it’s really up to what you prefer but these are a few general guidelines.

You can set your pool heater to any temperature you desire. The easiest way to do it is by dipping a manual thermostat inside your pool. If you decide it feels comfortable you don’t need to add a few degrees to the temperature. Turn the heater up if you feel too cold. You shouldn’t have to swim around to warm up. It should be relaxing the moment you jump inside unless you enjoy living on the edge.

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Switch The Heater Off When You’re Done

It’s pointless keeping your 400000 BTU pool heater switched on when you’re not using the pool, especially when you take into account how fast it works. This will save you a lot of money in the long run. Cover your pool and it won’t take too long to warm it back up. Just keep one thing in mind before you turn off the heater.

It should only be turned off if you’re not going to use the swimming pool for an extended period of time. You might like to do 100 laps of the pool before lunch to keep your heart strong. Maybe your kids will want to play in the pool later in the day when they get home from school. In these situations, you can keep it switched on.

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Heater Installation and Maintenance

Don’t get any funny ideas about installing a pool heater on your own. This includes carrying out any maintenance work on it. When a pool heater is installed and maintained by a professional it will improve its efficiency. You might have to pay money in the short term, but you’ll make it back in the long term. Unless something goes wrong you should call someone to have a look at it every 12 months.

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Why A 400,000 BTU Pool Heater Will Save You Money

We’ve looked at lots of modern 400000 BTU pool heaters today, but I’m sure a lot of people with swimming pools already have a heater. It’s clear you’re thinking about buying one, but like most people you could be sitting on the fence. The easiest way to change your mind is by showing you how old models waste tons of money because they’re so inefficient.

Let’s begin by looking at something really simple. I know 99 percent of people will already understand how heaters work, but it’s still good to see it written down. It makes you realize how much money you’re actually wasting. You have an imaginary pool heater sitting in your hands (which means you’re strong because they’re really heavy).

It’s 100 percent efficient, so for every $100 dollars you spend on gas you don’t waste a penny. This is a dream scenario everyone wants to see. Now imagine you’ve got a 65 percent efficient heater in your hands. For every $100 you spend, $35 dollars will be vanishing into thin air. You’re essentially throwing money away.

Most 400000 BTU pool heaters we’ve looked at today are around 95 percent efficient (100 percent heaters don’t actually exist). Let’s compare how much these models will save you compared to old ones. You’ll be able to do the math in your head to see if they’re worth it:

Heater Efficiency / 95% Efficiency / Annual Savings

• 55% / $580 / $420
• 60% / $630 / $370
• 65% / $685 / $315
• 70% / $735 / $265
• 75% / $790 / $210
• 80% / $840 / $160

Please Note: These savings are based on every $1,000 you spend each year. It’s easy to see a brand new 400,000 BTU pool heater will pay for itself if your current one isn’t efficient enough.

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Now Is The Time To Invest In A New Pool Heater

You should invest in a 400,000 BTU pool heater before you waste even more money. At least you know how much you’ll save on an annual basis. Don’t forget they come with a lot of other special benefits too, which should make your life a lot easier going forwards.

The only difficult choice you’ll have is deciding which one to buy. There is a cheat lots of people use on a daily basis. Click on the links and read the reviews past customers have left on Amazon. After you’ve consumed a few it will help you come to a final decision.

Read our indepth article on Inground Pool Heaters.

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For reference purposes only. These pool heaters are no longer available, or are in very limited supply.

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Pentair 460805 | MasterTemp Pool Heater

400,000 BTU Pool Heater — Natural Gas

Available in 4 different models:

• Pentair 460736 MasterTemp – Natural Gas
• Pentair 460737 MasterTemp – Propane
• Pentair 460805 MasterTemp – HD (Heavy-Duty) – Natural Gas
• Pentair 460775 MasterTemp – ASME – Natural Gas

Features:

• 400,000 BTU Natural Gas Heater
• Cupro-nickel heat exchanger
• Heats up fast, so no long waits before enjoying your pool or spa
• Best-in-class energy efficiency*
• Manual gas shutoff when service is required
• Eco-friendly MasterTemp is certified for low NOx emission and outperforms industry standards
• Rotating digital display allows for easy viewing
• Tough, rustproof exterior handles the heat and weathers the elements
• Electronic Ignition
• Compact design : Provides you with more options for installation.

DOCUMENTS for the Pentair MasterTemp series:

• ✓ View or download the INSTALLATION & USER GUIDE
• ✓ View or download the Pentair Installation HEATER CHECKLIST
• ✓ View or download the BROCHURE.

Overview

If you need a heavy-duty heater for your swimming pool the Pentair 460805 MasterTemp won’t let you down. It’s rock solid externally and internally. The shell of the pool heater can handle extreme hot and cold conditions, plus it’s rustproof and will always look fantastic. It’s a huge positive because you don’t want it affecting the aesthetics of your garden.

On the inside, it’s got a few features to protect the heater including the popular cupronickel heat exchanger. A water pressure switch won’t let the unit overheat if there is a problem with your pool. If the water temperature exceeds factory setting limits it will automatically shut itself off. You’ll need to also keep an eye on the pool pH levels to extend the lifetime of the heat exchanger.

Diagram showing how Pentair MasterTemp Pool Heaters work

A 400,000 BTU pool heater will obviously heat your pool very quickly, but there are another couple of features you’ll love. I’m sure you care about how much the unit will cost to run every month. Natural gas isn’t too expensive to begin with, but the Pentair 460805 MasterTemp is extremely efficient too. Also, it’s perfect for the environment because NOx emissions outperform industry standards.

If any work needs to be performed on the 460805 MasterTemp you can switch the gas off manually. It’s got an easy-to-read LCD digital display that rotates around to help you see it wherever you are. The advanced diagnostics will tell you when something is wrong, plus it will tell you exactly what the problem is. In other words, it’s easy to use even if you don’t have much experience with gas-powered pool heaters.

Learn more about MasterTemp pool heaters by visiting the Pentair site.

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VIDEO | Behind the Scenes — Working at Hayward

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Hayward H400FDNASME | Universal H-Series / Discontinued

400,000 BTU Pool Heater — Natural Gas : Commercial ASME

Features:

• Patented Cupro Nickel Finn Plate heat exchanger with bronze header as standard
• Independent left or right side electric, water and gas connections
• 2in x 2 1/2in CPVC flanged connections
• ASME pressure relief valve included as standard
• Electronic lock-out feature prevents unauthorized access to configuration settings
• Easy installation and service via access of single front panel
• Easy gas valve adjustment
• Easy dual voltage conversion with fuse-protected circuit boards
• Texas Heater Kits Available
• 3 Years Parts and Labor

Overview

Look at the model number on this 400000 BTU pool heater and you’ll see an ASME label attached at the end. It stands for ‘American Society of Material Engineers’ in case you were wondering. The Hayward H400FDNASME takes advantage of a ASME pressure relief valve to ensure system safety. It’s the best choice if you plan on using your swimming pool all the time.

The ASME heater was actually developed to be used in commercial pools, which will be kept running non-stop during opening times. Luckily, they’re ideal for residential pools too, even if you don’t plan on swimming for an entire day. This model has a low-lead bronze header with a patented bypass design, which will use up to 18 percent less energy than conventional units.

Everyone who purchases a Hayward H400FDNASME Universal H-Series pool heater will live in different areas around the country. The weather conditions will never be identical in two places, but it won’t affect the 400000 BTU pool heater. It’s thanks to the forced draft combustion system. Air will move through the combustion chamber at a precise flow rate, which will eliminate external conditions.

Do you worry about keeping an expensive piece of equipment in your garden? You have to remember this Universal H-Series pool heater weighs 160 pounds, so nobody will be able to pick it up and carry it away. Gas heaters will have pipes attached making it even harder to steal. Nobody will even be able to mess around with the temperature. The lock-out feature will stop them in their tracks.

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TRANE TR400NA : Discontinued

400,000 BTU Pool Heater — Natural Gas

✓  Also available in propane : TRANE TR400LP (400,000 BTU propane model)

Features:

• Durable cupro-nickel heat exchanger
• Excellent hydraulic efficiency saves energy
• Low NOx emissions meet all air quality emission standards
• Easy retrofit installation
• Patented polymer header design provides superior hydraulic performance to save energy and protect against the damaging effects of erosion from high flow conditions
• Intuitive and easy to read L.E.D. Control Panel provides digital temperature readout, diagnostics and electronic ‘lock-out’ of temperature set-point

✓ View or download the BROCHURE for Trane pool heaters.

Overview

The LED digital control panel on the TRANE TR400NA 400000 BTU pool heater stands out. It’s got most of the usual things you would expect in a world-class unit. It will give you a temperature reading at all times, you’ll be able to lock in a certain temperature to make your life easier, plus it has built-in diagnostics. It’s also accurate, which is what you should expect when spending this much money.

All TRANE units have been built with cupro-nickel heat exchangers, so they’re definitely the best in the business. The reason they’re so coveted boils down to three main things. The cost of the heaters won’t break the bank, so every unit is affordable to the average person. They will also keep going for years and years if you treat them with care. On top of that, superb energy efficiency makes them legendary.

If you want a TRANE 400000 BTU pool heater they’re simple to retrofit. You won’t be able to do it yourself, but it will take a professional a few hours. The exterior shell is built to last in extreme weather conditions, plus it’s more attractive than your average pool heater too. It will look good in your garden if you manage to see it. The dimensions of the TR400NA are only 36.5 x 29.5 x 24 inches.

We’re going to delve into the specifics of how pool heaters work later in the article, but let’s just say cold water enters and warm water flows out. A pool heater needs hydraulics to help you achieve this while maintaining exceptional energy efficiency. The system on the TRANE TR400NA uses a patented polymer header design to save energy while protecting the unit from problems like high flow conditions.