Fault High Limit - Jandy JXi. Just can't diagnose!

[tunnellscott]

My Jandy JXi is throwing the Fault High Limit error. I've read every thread on the topic, of which there are many. But can't figure out what's going on.

I replaced both high limit switches but it threw the error again. I definitely don't have a flow problem - the filter is clean and the spa bubbles vigorously.

Tonight, the heater ran for 5 minutes, taking the water temp from 66 to 71 in those five minutes. Then it threw the fault and shut off for 1-2 min, and then resumed again.

What else could it be?

 

[1poolman1]

My Jandy JXi is throwing the Fault High Limit error. I've read every thread on the topic, of which there are many. But can't figure out what's going on.

I replaced both high limit switches but it threw the error again. I definitely don't have a flow problem - the filter is clean and the spa bubbles vigorously.

Tonight, the heater ran for 5 minutes, taking the water temp from 66 to 71 in those five minutes. Then it threw the fault and shut off for 1-2 min, and then resumed again.

What else could it be?

Replacing the limit switches because they are doing their job is not the answer. That error is virtually always a waterflow problem. If there is no problem with the waterflow from outside the heater, the issue is probably internal. Start with the internal bypass and thermal regulator. About $125.00 for both at Wild West Pool Supply.

 

[tunnellscott]

Replacing the limit switches because they are doing their job is not the answer. That error is virtually always a waterflow problem. If there is no problem with the waterflow from outside the heater, the issue is probably internal. Start with the internal bypass and thermal regulator. About $125.00 for both at Wild West Pool Supply.
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Thanks! If you have any particular interest in Wild West Pool Supply, I'd be happy to purchase from them. Can't find those specific parts on their site, however. Got any links? If not, thanks again! Found them on some other pool supply sites.

 

[1poolman1]

Thanks! If you have any particular interest in Wild West Pool Supply, I'd be happy to purchase from them. Can't find those specific parts on their site, however. Got any links? If not, thanks again! Found them on some other pool supply sites.

I've done business with Wild West Pool Supply when a product wasn't available at a local wholesaler. Other than that, no other info or interest in the company.

Zodiac Pool Equipment Bypass Kit, Zodiac Jandy JXi 200/260/400 | R0589800

Zodiac Pool Equipment R0589800 Bypass Kit, Zodiac Jandy JXi 200/260/400

www.wildwestpoolsupplies.com

Zodiac Thermal Regulator Valve Kit, Jandy JXi 200/260/400 | R0589700

Zodiac R0589700 Thermal Regulator Valve Kit, Jandy JXi 200/260/400

www.wildwestpoolsupplies.com

 

[Ccryder5]

Replacing the limit switches because they are doing their job is not the answer. That error is virtually always a waterflow problem. If there is no problem with the waterflow from outside the heater, the issue is probably internal. Start with the internal bypass and thermal regulator. About $125.00 for both at Wild West Pool Supply.
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After changing out both of my high limits…and still having a high limit fault problem with my JXI 400…. it ended up being a bad thermal regulator valve. Thanks for posting this!