BoilerFaultCodesYour boiler is failing to light the gas to create heat, so the system has shut itself 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: Ignition Lockout
What causes this fault?
This fault occurs when the boiler tries to light the gas but fails to detect a flame after several attempts. The most common reasons are a lack of gas supply to the unit, a worn-out spark plug that can no longer create a flame, or a faulty internal component that controls the gas flow.
This fault is more frequent during extreme cold snaps, as frozen external gas regulators or blockages in the condensate drainage pipe can prevent the ignition process from completing.
DIY fix possible
Check if other gas appliances, like a cooker, are working to confirm gas supply.If it is freezing outside, check if the white plastic condensate pipe leading outdoors is frozen.Press the 'Reset' button on the boiler control panel once.
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like 4.3 — 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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