BoilerFaultCodesYour boiler is failing to light the gas flame, meaning it cannot provide heat 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: Appliance does not start: Attempts to ignite during start failed. Faults in the gas supply such as: Gas meter or gas pressure detector defective, Air in gas, Gas flow pressure too low, Main gas cock closed. Faults in the gas fitting, wrong gas setting, igniter defective, ionisation current stopped, faulty earthing, electronics defective
What causes this fault?
This fault occurs when the boiler tries to light the gas flame but doesn't detect one after several attempts. The most common reason is a disruption in the gas supply, such as an isolated meter or a blockage, though it can also be caused by worn-out spark components that are no longer strong enough to ignite the fuel.
This fault is frequent during the first cold snap of winter, as older gas valves can stick after being inactive during the summer or external gas meters may be affected by freezing temperatures.
DIY fix possible
Check if your gas emergency control valve (usually by the meter) is in the 'on' position.If using a prepayment meter, ensure you have sufficient credit and the valve hasn't locked.Try resetting the boiler by pressing the flame symbol with a cross through it for five seconds.
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A boiler cover plan would cover faults like F.28 — 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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