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Why Did My Pool Heater Break?

Early pool heater failure
With the cost of a pool heater being well into the thousands of dollars many pool owners will be left asking "why did my heater break?" or at least wondering why their heater failed much sooner than they were expecting it to. It used to be that you could get 25 or more years of service life from a natural gas or propane pool heater, but those days are long gone. 25+ years ago manufacturers were still attempting to build products that lasted as long as possible as a point of pride. Let's be realistic in that those days are long gone. Product manufacturers figured out long ago that making something that lasts forever is not exactly good for business, where making a product that needs to be replaced fairly regularly can lead to record breaking profits. This is a reality of the world we live in and I am hard pressed to think of a product that suffers from this throw-away mentality more than pool heaters.

If you buy a new pool heater you can expect to pay anywhere from $2000 to $5000 or more, especially when you factor in the electrician, gas fitter and pool company that will need to be involved with the process. Imagine your surprise if this significant investment broke irreparably and you needed to replace it entirely in only a few years time. This is, unfortunately, something that pool professionals encounter all of the time. I have seen heaters failed, and not covered by warranty, after as little as three months of operation. I have also seen three heaters installed on the same pool, and subsequently all failed, within a three years time frame...and again these failures were deemed to be outside of what any warranty would cover, if you can imagine that.

So what is going on here that is causing these expensive pool heaters to fail so readily? Is it just a matter of totally cheap manufacturing? While heaters are not made to last multiple decades like they used to be, you should at least be getting five to ten years of service life from yours, with an average of around seven years for many being installed today. Most of these will require service and then will continue to operate past this point, but many will also fail beyond the reasonable scope of repair. As an industry insider I can see what is happening here, and to what extent you can protect yourself from this situation, but most of the pool owners reading this will not be able to appreciate the reality of the situation.

Imagine that you paid a contractor to install a pool heater for you. They said you needed an electrician as well, so you got one of those and now everything is up and running. One year later your heater is leaking profusely and the water in your pool is cold. You have a service call from the contractor who sold you the heater, or the manufacturer warranty representative, and they tell you the heater was not installed correctly, and the internal damage is from poor water chemistry and you will receive no warranty coverage for the heater whatsoever. Further to this the damage is so severe that the best recommended course of action is to buy a new heater. Does this sound preposterous to you? It does to me, and yet this is so-freaking-common it would blow your mind. Let me break down for you all the ways in which this situation was allowed to happen.

Pool Heater Early Failure

When a pool heater is installed it needs to be connected to the equipotential bonding grid, along with all other metal components in and around the pool area and equipment. This requirement is inspected during modern day pool installations, at least in most areas, but who knows if your existing pool was bonded properly or not. Supposing the pool was bonded correctly, who was responsible to connect the new heater to the existing bonding grid? There is no inspection for connecting the bonding grid for peripheral items added after the initial construction of the pool...again, at least in most areas. The pool professional should know about this requirement, but most often they do not.

Similarly the electrician should know about this but in most cases if you hire them to hook up a piece of equipment that is exactly what they do - nothing more and nothing less. In the end nobody checks for the bonding connection, and you, the pool owner, have no idea that something like this is required so you do not even know to ask about it until you have had an early failure of your heater and you find yourself here reading this article.

I'm not done yet. The heater was not bonded, which certainly it should have been, but also perhaps you pay for cheap weekly pool service and the company that services your pool does something that they definitely should not be doing - putting chlorine pucks in your skimmer basket or your pump strainer basket. It has been known for decades to not do this and yet it is just so darned convenient...except for the fact that heavily chlorinated water is constantly cycling through your heater and managed to rot the internals completely. Pucks in your skimmer basket is one of the surest ways to prematurely shorted the service life of a pool heater...but not the only way. Check out all of the ways that the longevity of your pool heater can be compromised:

pH imbalance - By and large pool owners have very little appreciation for how important pH balance is in the water. Other than being aware that balancing the pH is a thing you need to do, most people do not appreciate just how important this is to do for the longevity of the pool equipment and integral pool components...not just for bather comfort! The pH scale is logarithmic meaning that a pH of 7.0 is ten times more acidic than a pH of 8.0, and a pH of 6.0 would be 100 times more acidic than a pH of 8.0. When you consider this you can see that when your pH is a little out of range, it is actually ridiculously far out of range and this very much matters to metals that are submerged within the water. Even moderately poor balancing of your pH levels can cause significant damage to the internals of your pool heater.

Chlorine injection without check valve - If you have any type of system that injects chlorine into your pool plumbing system then you need to be aware of the fact that chlorine can track backwards and collect in your heater during times when the pool pump is turned off. Chlorine puck feeders (erosion feeders) must have a check valve in between the heater and the chlorine feeder according to all manufacturers. Salt water chlorinators have fallen under the same guidelines for some manufacturers, and not others, and then some have changed their minds after many years of saying one thing or the other. The bottom line is that you might need a check valve in between a salt water chlorinator cell and a heater, or you might not, but $50 to protect against even the potential for damage to your heater sounds like a good deal to me. Pool heaters are usually the most expensive piece of equipment on the pad, and while some manufacturers are okay with you not having a check valve with a salt system, they also do not pay for your heater if it does fail sooner than you had hoped for. Since it is yours, I suggest you go the extra mile and protect yours in any way you can. Here is more information about pool heaters and check valves.

No sacrificial anode - Does your pool have an inline sacrificial anode installed? You should. A sacrificial anode is used to protect dissimilar metals that are submerged in salt water. Chlorine is derived from salt so if you use chlorine in your pool, which you should, then you have a measurable salt level. This in turn means that you should have a sacrificial anode installed to help protect metals within your pool system. Of all of the metals to protect the internals of your pool heater are the most likely to have a problem. Installing a sacrificial anode and connecting it to your bonding grid is a must if you want to protect your heater, and your pool, as much as possible.

Salt water pools - Continuing with the above example of every pool needing a sacrificial anode, it is even more important for salt water pools to have one. The rate of galvanic activity rises as the salt level in the pool rises. A salt water pool, while only 3000 parts per million of sodium, versus ocean water at 35,000 parts per million, still has a salt level elevated enough to put metal components within the pool system at potential risk for early failure. Mitigating the risk for damage from galvanic corrosion is critical for salt water pool owners who want their equipment to last as long as possible.

Adding chemicals through the skimmer - Even today you don't need to look very far to find someone who adds chemicals to their pool through the skimmer. Whether this is chlorine pucks in the skimmer basket, or pretty much any other chemical addition, you almost universally want to avoid this practice if you want your pool heater to last as long as possible. It is fairly universally accepted among pool equipment chemistry leaders that cyanuric acid and phosphate remover are the only chemicals that should even possibly be added to the skimmer. DE powder is also acceptable for pools with diatemacious earth filters as this is how you charge them. Otherwise just adopt the idea that diluted chemicals are better than concentrated chemicals when it comes to getting the most life out of your pool heater.

Not servicing the heater - Repairing a broken heater is one thing but did you know that you should pay for heater service before you have a problem in the first place? Pool heaters burn propane and natural gas and part of this process, just like an internal combustion engine in your car, is to carefully mix fuel and air together at a very specific ratio. Any deviation from the exact ration results in a less efficient burn of the fuel which results in lowered performance of the heater, as well as the accumulation of soot within the heater. A spring service cleaning is recommended for all pool owners. If you run your heater all year long this is a good chance for an expert to open things up and clean your heater, and for pools in cold climate areas this will allow for removal of leaves, pests and spiders which notoriously are attracted to pool heaters. This regular service is well worth the money if you want your heater to run optimally, and for as long as possible.

Inadequate air flow - Along the same lines as the example above about the ration between fuel and air, your pool heater needs both adequate ventilation as well as enough passive air flow within the room it is contained. If you have your heater completely outside then this does not apply however many indoor heaters do not have the amount of air flow that they need. Pool heaters are absolutely gigantic in terms of how much fuel they burn...like ten large BBQ units all running on full blast at the same time. If you choke off the air supply for your heater by stuffing it in the corner of a small shed, or in a closet in your basement, then you might find that it does not burn as cleanly as it should. Also worth noting is failure to provide adequate ventialation, or putting things too close to the heater, can easily result in a fire so be sure to respect these powerful appliances. Make sure your heater has loads of passive ventilation and ensure that you follow all manufacturers installation instructions for vent sizing and installation.

Improper storage of chemicals - A mistake that is all too easy to make, and something that can end up costing you a lot of money, is that you need to be aware of where you store your pool chemicals. Chlorine, namely, is the worst offender and far too many pool owners find out the hard way that you should never store chlorine in enclosed rooms with pool equipment (or other expensive tools / metal things). Regularly storing chlorine of any kind, liquid, pucks or granular, can result in off-gassing to enough extent that metal items within the room can become damaged. In severe cases of mishandling and storage of chlorine you can ruin metal components and tools completely. Chlorine should be stored away from other chemicals and not within closed pool rooms and sheds.

High sanitizer levels - While is was mentioned vaguely above it warrants mentioning again that failure to properly manage and balance your water chemistry can, and will shorten the service life of your heater. One of the worst situations to have is high chlorine levels. High chlorine levels are specifically hard on pool heaters, and the unique situation of high chlorine levels in conjunction with low pH levels will almost surely result in damage to your pool heater. You should endeavor to never have chlorine levels in excess of perhaps five parts per million, however there will be times that you need to exceed this, either accidentally or on purpose as part of a breakpoint chlorination process, and this is why it is a good idea to install a bypass for your heater. A bypass is a configuration of valves such that you can remove your heater from being included with the filtration of the water with the turn of a few valve handles. perform your chemical service and then return the heater bypass to the original position once the water chemistry is back where you want it. Without a heater bypass then you will have times that you are exposing your heater to adverse chemical conditions and there is noting that you can do about it. One of the considerations with adding a zoned bypass to a pool heater is that some jurisdictions require a pressure relief valve on pool heaters that have a bypass installed, where direct in-and-out heaters are not required to have this additional $100 component. In a market competing by the dollar for your sale it is possible that recommending a zoned bypass, and subsequent pressure relief valve, would have priced them out of the game.

Who would have thought that pool heater longevity would be such a nuanced subject? All of this without even starting to talk about which brand of pool heater is the best...surely now you can see just how easy it would be to have a pool heater break sooner than it should through either ignorance or negligence. Hopefully you have not experienced an early pool heater failure but if you think that you have feel free to email Steve to see if there is any obvious reason that yours has failed...and hopefully you can avoid repeating this early pool heater failure with your next installation.

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