Select a fault code

Annual service is due. Not a fault.

Gas valve fault detected — the boiler cannot safely control gas flow.

Fault detected in the external controls wiring.

The fan or flue system is not operating correctly.

The flow temperature sensor has failed or is reading incorrectly.

Boiler has overheated and the high-limit thermostat has cut out.

The boiler safety thermostat has tripped due to overheating. This is a protective shutdown.

The boiler has failed to ignite after multiple attempts.

Internal electronics fault detected on the main circuit board.

System water pressure has dropped too low for safe operation.

Flame detected when burner should be off — indicates a gas valve or detection fault.

Fan is not operating at the correct speed.