BoilerFaultCodesYour boiler was working but has suddenly turned off because the flame has gone out and it cannot manage to relight itself.
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 successfully starts but lose its flame while it is trying to heat your home or water. The most common reasons are a temporary interruption in the gas supply, a blocked flue, or internal components like electrodes becoming too dirty to detect the flame. It can also be caused by a buildup of debris in the condensate trap preventing the burner from staying lit.
This fault is more common in winter, as frozen condensate pipes can cause a backup of water that effectively 'drowns' the flame.
DIY fix possible
Check if other gas appliances, like a hob, are still working to ensure your gas supply hasn't been interrupted.If it is freezing outside, check the condensate pipe (the plastic pipe leading outside) for ice and defrost it with warm water.Press the reset button (a flame symbol with a cross through it) for five seconds to see if the boiler restarts.
Find a Gas Safe engineer
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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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