BoilerFaultCodesYour boiler thinks it still sees a flame even though the gas supply has been turned off, which is a safety conflict.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: Ionisation signal present after gas has been shut off
What causes this fault?
This fault occurs when the boiler's sensors detect heat or a residual flame signal even though the gas valve has been commanded to close. The most common reason is a gas valve that is physically leaking or failing to shut tightly, or a faulty sensor/circuit board that is incorrectly 'seeing' a flame that isn't really there.
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 FA — no call-out fees, no surprises.
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