BoilerFaultCodesYour boiler has failed to light after several attempts, meaning it has shut down as a safety precaution and will not provide heating or hot water.
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 itself several times but fails to detect a stable flame. The most common reasons are a lack of gas supply to the unit, a dirty ignition component that can no longer create a spark, or a debris-clogged burner.
This issue often surfaces during the first cold snap of winter when components that have been idle over summer are suddenly put under increased strain.
DIY fix possible
Check if other gas appliances in your home, such as a gas hob, are working to ensure gas is reaching the property.Ensure your pre-payment gas meter has credit if applicable.Press the 'Reset' button on the boiler control panel once to see if it restarts. Only attempt this three times maximum.If it is freezing outside, check that your white plastic condensate pipe leading outdoors is not frozen and blocked.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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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