BoilerFaultCodesYour boiler has failed to ignite and is not receiving a steady gas supply or spark, meaning you currently 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: Ignition fault
What causes this fault?
This fault occurs when the boiler tries to light but fails three times in a row, leading to a safety shutdown. It is physically caused by a lack of gas reaching the burner or a failure in the ignition system, such as a worn-out spark electrode or a faulty gas valve. If you have a prepay meter, check that you have credit, as a lack of fuel is a frequent trigger for this error.
In extremely cold weather, this code can be triggered if the external gas regulator freezes or if there is a blockage in the condensate discharge pipe.
DIY fix possible
Check if your gas meter has credit (if on prepay)Ensure your gas stopcock and other gas appliances, like a cooker, are workingPress the Reset button (indicated by a flame icon with a cross) 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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Glow-worm Flexicom 18sx is discontinued — time for a new one?
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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