Select a fault code

Fan speed outside permitted operating range.

PCB relay controlling gas valve has faulted.

Condensate pipe blocked or frozen.

System pressure below minimum operating level.

The flow temperature sensor has developed a fault.

Return temperature sensor out of range or failed.

High limit thermostat has cut out due to overheating.

Safety thermostat tripped — boiler overheated.

Boiler failed to ignite after repeated attempts.

Flame detected with no call for heat — gas valve not seating correctly.