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If you currently own a hot tub or are planning on buying one you may be curious about just how does your Hot Tub work? How does the heater in the Hot Tub heat it? Can I replace it? There are so many questions that may come to your mind. Luckily, we can provide the answers.

How does my Hot Tub’s heater work?

We will start the article by answering the question you came here for in the first place. So, how does a hot tub heater work? Unsurprisingly, it is rather complicated so we will be splitting the answer into multiple heading, Let’s go!

Heating the Water:

The first and primary purpose of a Hot Tub’s heater is to, of course, heat the water. This is done by using usually one (but can be more depending on the model, higher-end Hot tubs will usually feature more) pressure pipe. Using the pressure pipe, the water gets sent into the assembly where it will meet the heating coil, which wraps around the cold pin. The heating coil, using the electricity supplied to the Hot Tub, will then begin heating the water.

Bear in mind that this is what can damage your Hot Tub if you leave it on while it doesn’t have any water in it. The heating coil might overheat since there is no water to absorb the given off heat which can, therefore, damage your Hot Tub, luckily the whole heating part of your hot tub can be replaced depending on the model.

Distributing water (jetting) into the Hot Tub

After the water has been heated up in the Assembly by the heating coil, it will run into the distribution box where the water is then jetted out of various jet nozzles into the hot tub itself. Now imagine this happening continuously from the moment you turn your Hot Tub on and there you have it, that is how your Hot Tubs heater works.

However, considering you have come this far, you most likely have other questions about your Hot Tub’s heater, such as is it replaceable? can I repair it myself? How do I tell if my heating system has failed or if it is beginning to fail? If you have any of these questions to ask then be sure to continue reading the article as we will answer them.

How do I tell that my Hot Tubs heater has failed or is failing?

The worst nightmare of a Hot Tub owner is when the Hot Tub can no longer become hot. By diagnosing problems with your heater early it may allow you to salvage it or get a new one before your heater fails. There are various signs of impending heater failure, however, sometimes these can be fail-safes and could be just because the heater wasn’t configured by the manufactures correctly or something has altered it.

Problem #1: Hot Tub isn’t getting Hot

A common problem among many Hot Tub owners who have owned a hot tub for a couple of years is that the hot tub isn’t getting hot anymore. A lot of people just call it quits there and either get a new Hot Tub or just stop using the one they already own.

However, a common problem with a Hot Tub, especially one that has been in use for a long time, is that the filter may be clogged by debris and dirt that has accumulated over the years of usage. If you find debris, make sure to get rid of it and then give your filter a good clean and then try to use your Hot Tub again, it should be working. Even if your hot tub is still working, we recommend you to give your filter a good clean every once in a while as it will still give a big boost to heating time and maximum temperature.

If your filter isn’t clogged then it could be a problem with your Hot Tub’s thermostat. Call in someone to see if it is broken, and if it is, have them repair it for you. If it ain’t any of these, then the reason why your Hot Tub isn’t getting hot could be because your heater is broken, in which we recommend you get a new one.

Problem #2: Temperature Fluctuates

Another common, and an ultimately huge issue for anyone trying to have a relaxing time, is when your Hot Tub’s temperature begins to fluctuate. Lucky thing if it is temperature fluctuations is that it means the heater isn’t completely broke, the bad thing is that the only way to solve it is to have a professional come to repair either the temperature sensor, the thermostat or the heat sensors. Unfortunately, there isn’t a DIY method of solving Temperature Fluctuations unless you are already deeply knowledgeable about how to repair Hot Tub’s

Can I have my Hot Tub heater replaced?

A common misconception about cheap Inflatable Hot Tubs is that your gonna have to get a new one if the heater fails. Fortunately, this isn’t the case and almost all Hot Tubs from premium high-end ones to the inflatable low-end ones all can have their heaters replaced.

Obviously, before buying a new heater for your hot tub you will need to research what heater your model uses. A lot of Hot Tubs use Balboa heaters, however not all do. A lot of Hot Tub companies use their exclusive heaters and have made it so their hot tubs aren’t compatible with third-party heaters. This means that for some hot tubs you will need to buy your new heaters from the company you bought the Hot Tub itself from, which tends to be a lot more expensive than buying third-party heaters. Some companies have also made it impossible for you to replace a broken heater, which means you will have to buy an entirely new hot tub.


In conclusion, hot tub heaters are the most complicated yet most vital part of a Hot Tub. If yours becomes broken, then now you know what goes into heating your hot tub, which means you can identify what is wrong with your heater.

We hope we informed you of this article and we hope you will leave us knowing more about how your hot tub works. Thanks for reading and we hope to see you soon!