Hot tub not heating up? Here's what you should do

Hot tub heating up
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If you’re experiencing an unexpected problem with your hot tub not heating up, you’re in the right place. No matter what the cause of this problem is, there's no denying that it's super frustrating when all you want to do is kick back and relax in your spa. 

So, what are the common issues that can cause your hot tub to stop heating up? Well, even the best hot tubs and best inflatable hot tubs (opens in new tab) can stop working because of common error codes which stop water flow and heat in your tub. Here, we consult an expert in the hot tub industry to troubleshoot the reason behind your hot tub not heating up. 

Hot tub not heating up? Here's why

This issue might seem out of the blue to you, but what first time hot tub buyers often don’t know is that the hot tub not heating up is usually due to an error code designed to prevent damage to your expensive equipment. 

Our hot tub expert Edward Hallett explains that this is an inbuilt safety mechanism that stops water flow when it detects an interruption to the normal flow of water through your hot tub’s system. This is designed to stop any debris from forcing its way through your hot tub’s internal system and causing damage.

Edward Hallett
Edward Hallett

Edward oversees eCommerce activity for Happy Hot Tubs (opens in new tab), a premier online and in-store retailer of Hot Tubs and Swim Spas. Happy Hot Tubs is a family business that has been serving customers for over 35 years, making them one of the longest serving hot tub–specific businesses. 

Hot tub expert Edward Hallett tells us that the most common cause for a hot tub not heating up is a flow error. “Most of the time this will be dirty filters, restricting the flow of the water, which in turn causes the heater to cut off as part of a safety feature. Usually this produces an error message such as 'FLO' or 'LFL'. Users can easily check this by removing cartridge filters and giving them a thorough clean or by replacing them with new filters.” 

How to fix a hot tub not heating up because of a flow error

As our expert tells us, the likely cause of a flow error is a dirty or clogged filter. This will be alerting the system that the water is not flowing as it should and shutting off the flow and heat to the hot tub. 

Changing the filters for new ones is the best way to clear the blockage and error code, allowing the system to flow and heat up once again.

What if it’s a pressure switch error not a flow error?

If changing the filters doesn’t fix your hot tub not heating up then it’s possible you are dealing with a pressure switch error, not a flow error. 

We asked industry expert Edward Hallett what you should do if this is the case, “If a pressure switch is faulty then it will send the incorrect message to the board, which will then turn the heater off. In this situation, it is always best to contact your hot tub retailer as they will be able to easily diagnose this, confirm if this is a warranty or chargeable issue and fix the issue at hand.”

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Tanisha Fletcher

Tanisha started her career in commercial retail buying for one of Amazon UK’s Top 10 revenue grossing online homeware retailers. Years spent obsessing over homeware products made it an easy career switch to writing about them. Her freelance career has seen her craft customer-focused web content for brands big and small, as well as writing articles in the health, lifestyle, home and retail sectors.

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