BoilerFaultCodesYour boiler thinks a flame is present when it should be off, which is a safety lockout preventing the unit from starting.
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 sensors detect a flame after the burner should have switched off. The most common reason is a faulty sensing electrode sending a false signal, or a gas valve that is slightly sticking and allowing a tiny amount of gas to leak through when it shouldn't.
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 L6 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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