BoilerFaultCodesYour boiler is continuing to detect a flame even after it has been told to shut down, which is a safety precaution to prevent gas issues.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flame after a delay
What causes this fault?
This fault occurs when the boiler's sensors detect heat or a flame signal even after the gas supply should have been cut off. The most common reason is a gas valve that is failing to close fully or a faulty electrode that is sending a false 'flame present' signal to the main control board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like EF — no call-out fees, no surprises.
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