BoilerFaultCodesYour boiler has tried and failed to light the flame several times, so it has locked itself 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: Burner lock out indicator: Should the boiler fail to light it will attempt 2 re-ignition sequences, if the boiler still fails to light the burner lock out indicator will illuminate. This usually means that the gas supply is turned off or has not been purged of air.
What causes this fault?
This fault occurs when the boiler's internal computer tries to start a flame but cannot detect one after several attempts. The most common reasons are a lack of gas reaching the burner, a faulty spark plug that cannot create an ignition, or a sensor that fails to tell the boiler that the flame is actually lit.
This issue often appears after a long period of disuse during the summer or during extreme cold snaps when external gas meters or pipes are prone to freezing.
DIY fix possible
Check if other gas appliances, like a cooker, are working to confirm gas is reaching the property.Ensure your gas meter has credit if you use a prepay meter.Press the 'Reset' button (indicated by a flame with a line through it) and hold for one second.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 7 — no call-out fees, no surprises.
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