BoilerFaultCodesYour boiler is trying to start up but cannot light the gas flame required to 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: Either insufficient gas in the system, a defective electrode, ignition lead or electronic ignitor
What causes this fault?
This fault occurs when the boiler attempts to ignite several times but fails to establish a consistent flame. The most common reasons include a lack of gas reaching the burner, worn-out spark electrodes that can no longer create a flame, or a faulty gas valve that isn't opening correctly. This effectively acts as a safety shutdown to prevent the boiler from trying to operate without a fire.
This fault is more frequent during the first cold snap of winter, as gas valves and internal components can seize up after sitting idle during the summer months.
DIY fix possible
Check that your gas emergency control valve is open and you have credit on your meter.Test another gas appliance, like a hob, to ensure gas is reaching the property.Press the 'Flame' or 'Reset' button on the boiler control panel for one second.
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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Vaillant Turbomax Plus 824/828E 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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