BoilerFaultCodesYour boiler has tried to light itself three times but failed, meaning you currently have no heating or hot water because the gas flame isn't staying on.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Failure during start-up: Ignition unsuccessful
What causes this fault?
This fault occurs when the boiler is unable to detect a stable flame after several attempts to ignite. The most common reasons include a temporary interruption in the gas supply, dirty internal components that can't sense the heat, or a worn-out part that is failing to create the necessary spark.
This fault is more frequent during extreme cold spells, as sub-zero temperatures can cause external gas regulators or condensate pipes to freeze, blocking the boiler's operation.
DIY fix possible
Check if other gas appliances in your home, like a hob, are working to confirm gas supply.Ensure your gas pre-payment meter (if you have one) has credit.Try resetting the boiler by pressing the 'flame' or 'reset' button for three 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 F.28 — 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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