BoilerFaultCodesYour boiler has failed to light because it cannot detect a flame, which most likely means there is an issue with the gas supply or a part that ignites the fuel.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flame not detected
What causes this fault?
This fault occurs when the boiler attempts to start up but fails to detect a steady flame after several attempts. The most common reasons include a lack of gas reaching the burner, a build-up of carbon on the ignition parts, or a blockage in the pipe that carries away waste moisture. In some cases, the sensors inside the boiler may simply be worn out and unable to tell the computer that the flame is lit.
This fault is more common in winter, as a frozen external condensate pipe can cause water to back up into the boiler and prevent the flame from lighting.
DIY fix possible
Check that your pre-payment gas meter has credit and is turned on.Verify that other gas appliances in your home, like a hob, are working correctly.Gently press and hold the 'Reset' button for five seconds to see if the boiler restarts.In freezing weather, check if your external plastic condensate pipe has frozen and thaw it with warm water.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like EA — no call-out fees, no surprises.
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