How to Fix / Troubleshooting

Safety first: Turn off power at the breaker before opening the electrical compartment.

Check dedicated circuit: Ensure the furnace is on a dedicated circuit and that the breaker is correctly rated and not tripping frequently.
Inspect terminals: Open the electrical junction box on the furnace and verify that live, neutral, and earth connections are tight and not discolored.
Look for surge damage: Examine the PCB for signs of surge damage (burn marks, cracked components). If present, the board likely needs replacement.
Monitor voltage (professional): Have an electrician measure supply voltage under load to ensure it is within Roca’s specified range.

Warning: Working on live mains circuits is hazardous. If you are not trained, use a licensed electrician.

Furnace indicates power supply or voltage error, may reset randomly or not start

Possible Causes