BoilerFaultCodesYour boiler is failing to light the gas flame, which means your heating and hot water will not work until the system is reset or repaired.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Ignition fault
What causes this fault?
This fault occurs when the boiler tries to start but cannot establish a stable flame to begin heating your water. The most common reasons include a lack of gas reaching the unit, a worn-out spark plug that can no longer light the fuel, or a internal component failing to detect that the flame is actually lit.
This fault is more frequent during extreme cold snaps, as external gas meters or pipes can freeze and restrict the flow of fuel to the boiler.
DIY fix possible
Check that your gas emergency control valve is in the 'on' position.If you have a pre-payment gas meter, ensure you have sufficient credit.Press the reset button (indicated by a flame with a line through it) 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 F28 — 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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