Select a fault code
The boiler's gas type configuration does not match the detected gas supply.
Annual service reminder. The boiler is not in lockout.
A fault on the gas valve has been detected.
Problem with the external controls wiring or thermostat signal.
The fan or flue system is not operating correctly.
The flow NTC sensor has failed or is reading out of range.
The boiler temperature exceeded the safe limit. Often caused by poor circulation, a blocked heat exchanger, or a faulty pump.
The safety thermostat has activated due to dangerous overheating.
The boiler has failed to ignite. Common causes are low gas pressure, a faulty ignition electrode, or a dirty flame sensor.
An internal fault on the boiler's PCB has been detected.
System pressure has dropped below the safe minimum. This is a very common fault.
Flame signal present when burner is off. Gas valve or ionisation fault.
The fan is not running correctly. Combustion gases cannot be safely expelled.
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