BoilerFaultCodesYour boiler thinks a flame is present when it shouldn't be, which is a safety error that has caused the system to shut down for protection.
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 control system detects a flame signal at a time when the burner should be off, such as during the startup sequence or after the heating cycle has finished. The most common reasons are a faulty sensor that is incorrectly reporting a flame, or a gas valve that is letting a tiny amount of fuel through when it should be closed.
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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