HL or HIL displayed; spa shuts down or heater disabled.
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety first: Turn off power at the GFCI. Allow water to cool if it feels excessively hot.
- 1. Clean/remove filter: Take out the filter cartridge and rinse thoroughly. Run the spa briefly without the filter after restoring power to see if HL clears.
- 2. Bleed air: Loosen the heater union slightly to release trapped air, then retighten once water flows steadily.
- 3. Check circulation: Restore power and verify that water is moving strongly from the circulation return. If weak or absent, the circulation pump may be failing.
- 4. Inspect for scale: If your water is hard and the spa is older, mineral scale may have built up inside the heater, reducing flow and causing localized overheating. This usually requires heater replacement.
If HL trips repeatedly, do not continue resetting. Have a technician test flow rate, pump performance, and inspect the heater for internal blockage.
Repair Difficulty
Required Part
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