BoilerFaultCodesTechnical description
Permanent fault. False flame signal, short-term fluctuation of the mains, ionization current present even though there is no flame, the burner remains very hot (CO2 too high) or defective gas/air unit.
What causes this fault?
This fault occurs when the boiler's internal sensors detect a flame after the heating cycle has finished or identify that the burner assembly is dangerously overheating. The most common reason is a sensor incorrectly reporting a signal due to moisture or carbon buildup, or a gas valve that is failing to close fully and let the burner cool down.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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