BoilerFaultCodesYour boiler is trying to start up but cannot light the gas flame to 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: Failure to light (could be gas supply issue).
What causes this fault?
This fault occurs when the boiler's control system attempts to start the combustion process but fails to detect a stable flame after several attempts. The most common reasons include a lack of gas reaching the burner, worn-out spark electrodes that can no longer ignite the gas, or a fault within the gas valve itself.
This issue is more frequent during extreme cold snaps, as external gas meters or regulators can sometimes freeze, restricting the flow of gas to the property.
DIY fix possible
Check if other gas appliances, like a hob, are working to confirm gas supply.Verify that your gas meter has credit if you use a pre-payment meter.Reset the boiler by turning the selector switch to the 'R' position for five seconds.
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 E.04 – .10 — 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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