Water is not heating; temperature remains far below the set point even after many hours.
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: Turn off power before opening the control box or accessing the heater.
- Verify mode and set temp: Ensure the spa is in Standard mode and the set temperature is above current water temperature.
- Check for flow errors: Confirm there are no FLO, LF, or OH codes; resolve flow issues first.
- Feel heater tube: After running for 15–20 minutes, carefully feel the heater tube. If it is cold, the heater is not energizing.
- Inspect connections: Check heater wires and terminals for burns or loose connections.
Testing heater resistance and board output requires a multimeter and should be done by a qualified technician. Replace the heater assembly or control board as indicated by test results.
Repair Difficulty
Required Part
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