BoilerFaultCodesYour boiler has tried to start up several times but cannot establish a flame to begin heating your 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 ignite
What causes this fault?
This fault occurs when the boiler’s control system detects that a flame hasn't been successfully lit after several attempts, leading the unit to shut down for safety. The most common reasons include a lack of gas reaching the burner, a worn-out spark plug that can no longer create a flame, or a dirty internal component that is preventing the sensors from 'seeing' the fire.
This fault is more frequent during extreme cold snaps, as external gas meters or pipes can sometimes freeze or experience pressure drops that prevent enough fuel from reaching the boiler.
DIY fix possible
Check if your gas meter has credit and the isolation valve is openCheck if other gas appliances, like a hob, are working correctlyPress the 'Flame' or 'Reset' button for one second to restart the sequence
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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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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