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Hayward Pool Heaters

Hayward pool heaters Hayward represents arguably the biggest name in residential swimming pool equipment in North America. Since a gas heater is the most expensive piece of equipment on your pool equipment pad this is a subject that pool owners tend to research heavily before making a purchasing decision. Regardless of which heater you end up buying at some point you will end up researching Hayward pool heaters - this article will help you to understand which Hayward heaters are the best and what sizes they are available in. Also included is information about vent adapters and heating capability of each size of heater.

There are many brands of pool heaters that are worth considering. Pentair has a line of almond colored heaters as well as a second brand from a company acquisition in Sta-Rite. Both heaters while now under the ownership of Pentair were developed through different research and development channels and remain uniquely different unto themselves. Jandy (Zodiac) is also a common choice for pool heaters as are Raypak (Rheem). So how do you decide which brand will be the best pool heater for your pool? As a pool expert this is a question that I am asked very frequently. Every sales person will have their own way to highlight the specific benefits of their product, and every gas service technician will have a favored brand, make or model based on their individual experience in the field. At the end of the day there is no definitive winner as to what is the best pool heater on the market. All new heaters have the potential to provide you with years of trouble free and efficient heat for your pool, just as all pool heaters have the potential to be a lemon and break down within the first calendar year.


Scouring the internet for pool heater reviews is a great idea, but you can get lost in the confirmation bias. Whichever company sells the most heaters is likely to also be the company with the most negative reviews online. This is not an indication of a less-than-worthy product line, but more an indication of the number of products they have in the market currently. Reading negative reviews is almost certainly not going to help you to identify the best heater. At most you will be able to identify a few known issues to be aware of, but even still this information can be more misleading than anything else. If I, knowing what I know about the pool and spa industry, needed to buy a pool heater I would probably ignore negative reviews completely. I would instead focus my efforts on finding positive reviews for pool heaters. People complain loud and often when they are not happy, but you must be a very content customer to take the time to post a positive review for a swimming pool heater. Following this logic you will be able to identify specific elements to brands, makes and models that represent similar goals you hope to achieve. As someone who has worked in the pool and spa industry for over 25 years, and with specific experience doing heater sales, warranty and technical support on the national level, I can easily say that most pool heaters that fail early do so from poor installation. If you want to get the most life out of your new pool heater then make sure that yours is installed correctly. On the national level well less than 1% of heaters fail under warranty. Of the heaters that do fail under warranty over 90% of those are from incorrect installation or imbalanced water chemistry. If you really want to make sure that you protect your investment then be sure that it is installed correctly and that you maintain your water chemistry (most specifically sanitizer and pH levels) at all times.


To learn how to inspect your pool equipment for deficiencies you should watch this video series that includes 50 pool equipment installation reviews where you will learn how pool equipment fails with specific reference to how to install your heater so that it does NOT fail early.


Pool Heaters & Water Chemistry


You are researching pool heaters to buy and I am talking about pool chemistry...why would I do that? Being that I used to have national exposure to heater technical support and warranty issues for some of the largest pool heater suppliers in the world I have access to information that you do not have. I want to impress on you the importance of something you already know but most likely are not taking seriously enough. There are a number of circumstances that can result in a brand new pool heater being completely garbage in as little as 3 months! Even today I received an email from a distraught pool owner with a 3 month old heater now needing extensive repairs and the manufacturer denied their warranty claim. Why? Simple, the heater internals showed clear signs of chemical damage. Upon investigation of the installation it was determined that the heater was not bonded correctly and that there was a salt water chlorine system installed on the pool without a check valve in between the heater and the salt cell. The incomplete installation of the heater, combined with a short period of time where the water chemistry was off, was all it took to ruin a $3000 investment.


1) Your heater must be bonded on the outside casing (if metal)

2) If you have a salt water system you must have a check valve in between the cell and your heater

3) Keep your sanitizer levels and pH levels within normal range at all times (1-3ppm FC and 7.2-7.8 pH)

4) Install a sacrificial anode to help protect your heater (optional, not required for warranty coverage)

5) Have the heater cleaned & serviced every spring.




These are the major things that will make the biggest difference to how long you can expect your new pool heater to last. Almost every bad review that you might read on the internet about any specific brand, make or model of pool heater will likely have failed due to one or more of these reasons. In reality any major brand name of heater that is installed and maintained following these 5 steps is likely to outlast the majority of other pool heaters on the market. Brand has much less to do with longevity than the installation and maintenance of the heater. Ford and Chevrolet both make trucks. Although people will develop very strong opinions as to which they like better the truth is that either one, if maintained well, will last for a very long time. Pool heaters are no different.


Hayward Pool Heater Warranty

As a pool and spa expert with an online following I receive almost daily emails from people asking me what my favorite pool heater is. I have previously tried to avoid being brand specific as to which I endorse but the truth is that I use Hayward heaters more than other brands. There are a lot of reasons why I specifically like the Hayward brand for heaters. I have had a positive experience with them in my contracting years in both performance as well as with warranty support when need be. The availability and helpfulness of the warranty support process is an important factor for me. If you only buy and use one pool heater every 10 - 15 years then this probably will not apply to you. If you see as many heater installations as I do then the warranty process is a foregone conclusion. While you would not need to look very far online to find a strongly worded negative complaint about the Hayward warranty support team, I can only say that my personal and professional experience has been fantastic all around. In my experience I have found that Hayward goes above and beyond to support their products. This has a lot to do with my professional recommendation in this article to choose a Hayward heater for your pool.





Hayward Digital Pool Heaters

At the end of the day I have sold and installed more Hayward FD series heaters than every other brand put together. I still like Pentair, Sta-Rite, Jandy and Raypak heaters, and have installed each of them for various projects over the years, but the heater that I consider my "go to" is the Hayward Universal heater. The Hayward FD series of pool heater is a forced draft which means that it does not require an additional blower or venting system for outside applications. It is considered a "universal heater" since the water intake and outlet header can be switched internally, and the gas and electrical connections can be made on either side to accommodate any placement orientation needed on the equipment pad. This is a very handy feature that many people shopping for a pool heater may not think to consider. If there is a last minute change to the orientation of your pool equipment then you can be sure that the Hayward Universal heater will be able to accommodate the changes.




Model: Hayward H150FDN Universal Heater
Gas type: Natural Gas (also available in the H150FDP propane model)
Heater size: 150,000 BTU
Maximum pool size: 15' x 30' or smaller
Time needed to heat an 800 gallon spa by 30 degrees F: 100 minutes
Suitable for salt water pools: Yes
Vent adapter for indoor installations (for vertical venting): Vertical vent adapter
Vent adapter for indoor installations (for horizontal venting): Horizontal vent adapter




Model: Hayward H200FDN Universal Heater
Gas type: Natural Gas (also available in the H200FDP propane model)
Heater size: 200,000 BTU
Maximum pool size: 16' x 32' or smaller
Time needed to heat an 800 gallon spa by 30 degrees F: 75 minutes
Suitable for salt water pools: Yes
Vent adapter for indoor installations (for vertical venting): Vertical vent adapter
Vent adapter for indoor installations (for horizontal venting): Horizontal vent adapter



Model: Hayward H250FDN Universal Heater
Gas type: Natural Gas (also available in the H250FDP propane model)
Heater size: 250,000 BTU
Maximum pool size: 18' x 36' or smaller
Time needed to heat an 800 gallon spa by 30 degrees F: 60 minutes
Suitable for salt water pools: Yes
Vent adapter for indoor installations (for vertical venting): Vertical vent adapter
Vent adapter for indoor installations (for horizontal venting): Horizontal vent adapter




Model: Hayward H300FDN Universal Heater
Gas Type: Natural Gas (also available in the H300FDP propane model)
Heater Size: 300,000 BTU
Maximum Pool Size: 20' x 40' or smaller
Time needed to heat an 800 gallon spa by 30 degrees F: 50 minutes
Suitable for salt water pools: Yes
Vent adapter for indoor installations (for vertical venting): Vertical vent adapter
Vent adapter for indoor installations (for horizontal venting): Horizontal vent adapter



Model: Hayward H350FDN Universal Heater
Gas Type: Natural Gas (also available in the H350FDP propane model)
Heater Size: 350,000 BTU
Maximum Pool Size: 20' x 44' or smaller
Time needed to heat an 800 gallon spa by 30 degrees F: 43 minutes
Suitable for salt water pools: Yes
Vent adapter for indoor installations (for vertical venting): Vertical vent adapter
Vent adapter for indoor installations (for horizontal venting): Horizontal vent adapter





Model: Hayward H400FDN Universal Heater
Gas Type: Natural Gas (also available in the H400FDP propane model)
Heater Size: 400,000 BTU
Maximum Pool Size: 30' x 50' or smaller
Time needed to heat an 800 gallon spa by 30 degrees F: 37 minutes
Suitable for salt water pools: Yes
Vent adapter for indoor installations (for vertical venting): Vertical vent adapter
Vent adapter for indoor installations (for horizontal venting): Horizontal vent adapter



Model: Hayward H500FDN Universal Heater
Gas Type: Natural Gas (also available in the H500FDP propane model)
Heater Size: 500,000 BTU
Maximum Pool Size: 40' x 40' or smaller
Time needed to heat an 800 gallon spa by 30 degrees F: 31 minutes
Suitable for salt water pools: Yes
Vent adapter for indoor installations (for vertical venting): n/a
Vent adapter for indoor installations (for horizontal venting): n/a


When shopping for a pool heater you need to make sure that you get one that is big enough for your needs. If you want to see more information about how to calculate the exact size of heater that you need you can read this complete pool heater reviews article that discusses heater sizing as well as a comparison of all brands, makes and models of pool heater. If you are looking for a definite recommendation from an authority then the Hayward Universal Forced Draft heaters are one of the best pool heaters on the market. Combine this with high efficiency, low emissions and the versatility to connect the gas, electrical and plumbing from either side of the machine makes this a great overall choice for your heater for in ground pools.





Swimming Pool Steve

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