Troubleshoot: Flow Error on a Hydropool Hot Tub or Swim Spa

We’ve had a few calls about flow errors flashing on user's hot tub or swim spa topside controls lately. The script remains the same to troubleshoot and try to solve the issue before needing to call out the maintenance team from Hydropool North West! We'll discuss first steps below.

After a long week at work, you can’t wait to get back home and get in your hot tub. You lift the cover and what do you find? Cold water and a big flashing “FLO” error on the screen. Disaster. What can you do? Well, call a hot tub service engineer I guess…or maybe try these tips first!


What Does A Flow Error Mean?

A Flow Error, often displayed as “FLO” or “FL” on a control panel, means that your hot tub has detected a problem with the water passing through your system. This can even mean a low pressure or zero flowing water passing through your heater. When this occurs, your hot tub will shut down, to avoid overheating, and display a FLO error.


How Can I Fix it?

A flow error could be something or nothing. Following these steps will help you troubleshoot the issue and figure out if you need to call a technician.

Step 1:

Make sure your water level is high enough. Your water should be high enough to cover all your jets and inlets. Your user guide should tell you where to fill to, or there should be some indicator or marking on the hot tub. If your hot tub has a surface skimmer, ensure that the water level is high enough to enter the surface skimmer, and that there is no debris blocking any suction inlets.


Step 2:

Clean your filter. Your filter can become clogged with dirt, slowing down the flow of water, even if you can’t see it. Clean your filter with some spa-specific filter cleaner. Remember, your hot tub filter is only rated to last around a year. If it’s been a while since you replaced it, it might be time to buy a new one.

If you think it may be your filter causing the issue- try running your hot tub without it. If your FLO error goes away, it’s likely the issue.

Make sure there is no air trapped in the filter compartment, using the air release valve.


Step 3:

Your hot tub might have gate valves- which you’ll find inside the cabinet. If you feel comfortable doing so, it might be a good idea to check if one of them hasn’t accidentally been closed, or slipped closed.

You could have an air lock in your circulation pump, especially if you’ve recently refilled your tub, to clear this follow our air-lock clearing guide.


Step 4:

Restart your hot tub. Flick it off and on again at the isolator. Check if the error goes away, keeping an eye out for the normal flow of water you would see when your hot tub is working normally. Check the hot tub at regular intervals to see if the error returns.

Can you see bubbles, the flow of water, and hear the pump running?

If all is well your hot tub should begin to heat as normal.

If you are still experiencing problems, call your hot tub dealership or technician (That might be us!) They may be able to suggest solutions specific to your brand of spa.


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