BoilerFaultCodesYour boiler was working but the flame went out and it cannot manage to light itself back up.
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 operation: Re-ignition unsuccessful
What causes this fault?
This fault occurs when the boiler is running normally but the flame suddenly disappears and the system fails to relight it. The most common reasons include a temporary interruption in the gas supply, a blocked flue vent, or a buildup of carbon on the ignition electrodes that prevents them from detecting the flame.
This fault is more frequent during extreme cold spells, as frozen external condensate pipes can cause the boiler to back up and extinguish the flame.
DIY fix possible
Check if other gas appliances (like a hob) are working to ensure gas is reaching the propertyCheck if your gas meter has credit and the isolation valve is openPress the 'Reset' button (indicated by a flame with a line through it) 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.29 — 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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