Select a fault code

No gas pressure detected at the gas valve.

Boiler attempted to ignite but flame was not established.

Gas valve not responding correctly to control signals.

High limit safety thermostat has tripped due to excessive temperature.

Fan speed is incorrect or flue is restricted.

Circulation pump not running or seized.

System pressure has dropped below operating minimum.

NTC temperature sensor on the flow has failed.

NTC temperature sensor on the return has failed.

Hot water temperature sensor has failed.

Internal error on the control board.

H on the display simply means the boiler is in heating mode and operating correctly.

Boiler is running in domestic hot water mode. Normal operation.