BoilerFaultCodesYour boiler thinks it sees a flame even though it hasn't signaled the system to start, causing it to shut down for safety.
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 control system detects an electrical signal signifying a flame is present, even though the gas valve should be closed. It is usually caused by a damaged flame sensing probe sending a false signal or a moisture buildup on the internal wiring that creates a small electrical leak. In some cases, it can be a sign that the main control board is malfunctioning and misinterpreting data from the sensors.
This issue can occasionally follow periods of heavy rain or high humidity, as moisture entering the flue or casing can interfere with the sensitive electrical components that detect the flame.
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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