BoilerFaultCodesYour boiler has tried to light several times but has been unable to establish a flame, meaning you have no heating or hot 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 during start-up: Ignition unsuccessful
What causes this fault?
This fault occurs when the boiler attempts to ignite but cannot confirm that a steady flame has been established. The most common reasons include a lack of gas reaching the burner, a worn-out ignition spark, or a buildup of carbon on the sensor that detects the heat.
This fault is more frequent during extreme cold snaps, as the external gas regulator can freeze or the condensate pipe can become blocked with ice, preventing the boiler from firing.
DIY fix possible
Check if other gas appliances, like a cooker hob, are working to ensure gas is reaching the property.If you have a prepayment meter, check that you have sufficient credit.Press the Reset button (indicated by a flame with a cross through it) for one second to see if the boiler restarts.
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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