BoilerFaultCodesYour boiler thinks it sees a flame when there shouldn't be one, so it has shut down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: False Flame Lockout
What causes this fault?
This fault occurs when the boiler's internal sensor detects a flame signal even though the gas valve should be closed and the burner turned off. The most common reason is a faulty sensing electrode that is sending a false signal, or a failing control board that is misinterpreting electrical interference as a live flame.
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 L6 — no call-out fees, no surprises.
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