BoilerFaultCodesYour boiler has tried to light several times but cannot establish a steady flame, likely because gas isn't reaching it or the spark is failing.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Interruption of gas supply or ignition failure (5 attempts)
What causes this fault?
This fault occurs when the boiler has tried to ignite five times but failed to detect a flame, causing the system to shut down for safety. It is most commonly caused by an interruption in the gas supply, a blocked burner, or a worn-out spark electrode that can no longer create a strong enough light. In some cases, a faulty internal sensor may simply fail to 'see' the flame even if the boiler has actually lit.
This fault is frequently seen during extreme cold snaps when the external condensate drainage pipe freezes and backups, preventing the boiler from completing its ignition cycle.
DIY fix possible
Check that your gas meter has credit and the emergency control valve is open.Verify if other gas appliances, like a hob, are working to confirm gas supply.Check if the condensate pipe (outside white plastic pipe) is frozen or blocked.Press and hold the reset button for five seconds.
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