Display shows “OHH”; spa shuts down completely; may not respond to controls until cooled.
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 immediately. Do not attempt to reset repeatedly without finding the cause.
- Allow full cool-down: Leave the cover open and let the spa cool for several hours. Verify water temperature with an external thermometer.
- Check circulation: After cooling, restore power and confirm that the SilentFlo circulation pump runs and that there is strong flow at the heater return. Weak or no flow can cause localized overheating.
- Inspect heater connections: With power OFF again, open the equipment bay and inspect the No-Fault heater terminals and wiring for signs of burning or melting.
- Sensor test: If you have a multimeter and experience, you can ohm-test the temperature and high-limit thermistors and compare to Hot Spring resistance charts. Replace any sensor that is out of spec.
Because OHH indicates a serious overheat, professional diagnosis of the heater circuit and control board is strongly recommended.
Repair Difficulty
Required Part
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