BoilerFaultCodesYour boiler thinks a flame is present even though it hasn't been safely ignited, causing the system 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: False Flame Lockout
What causes this fault?
This fault occurs when the boiler's internal sensor detects a flame signal at a point in the starting sequence where there shouldn't be one. The most common reason is a faulty flame sensing electrode that is sending a wrong signal to the control board, or a gas valve that is leaking a tiny amount of gas into the burner area before it is supposed to open.
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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