BoilerFaultCodesYour boiler thinks it sees a flame even though it hasn't been told to turn on, which is often caused by a false signal from a sensor or a moisture issue.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flame detected when the burner is off
What causes this fault?
This fault occurs when the boiler's safety system detects an electrical current that mimics a flame even though the gas hasn't been ignited. The most common reason is moisture or carbon buildup on the ionisation probe, but it can also be caused by a fault in the internal control board sending an incorrect signal.
This issue is more frequent during periods of heavy rain or high humidity, as moisture can enter the air intake and interfere with the sensitive electrical components.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F7 — no call-out fees, no surprises.
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