BoilerFaultCodesYour boiler is failing to light the gas or cannot confirm that a flame is present, meaning it has shut down for safety.
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's control system attempts to light the burner but cannot confirm a flame is present. The most common reasons include a lack of gas supply to the unit, worn-out ignition components that can't create a spark, or a dirty internal sensor that can no longer 'see' the flame even if it is lit.
This fault is more common in winter, as extremely cold temperatures can cause the external condensate drainage pipe to freeze and back up, preventing the boiler from lighting safely.
DIY fix possible
Check if other gas appliances in your home, like a hob, are working to confirm your gas supply is active.If it is freezing outside, check if your white plastic condensate pipe is blocked with ice.Press and hold the 'Reset' button for five seconds to see if the boiler restarts.
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A boiler cover plan would cover faults like EA — no call-out fees, no surprises.
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