BoilerFaultCodesYour boiler is failing to light the flame needed to heat your water or radiators, causing the system to 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 attempts to ignite but cannot establish or maintain a stable flame. The most common reasons include a lack of gas reaching the burner, worn-out ignition components that can't create a spark, or a sensor that has become too dirty to detect the flame.
This fault is significantly more frequent during extreme cold snaps, as the external condensate pipe can freeze and back up, preventing the boiler from lighting.
DIY fix possible
Check if other gas appliances in your home (like a hob) are working to ensure gas is reaching your property.Inspect the white plastic condensate pipe outside for signs of ice; if frozen, gently thaw it with warm (not boiling) water.Press and hold the 'Reset' button for five seconds to see if the boiler restarts.
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like EA — no call-out fees, no surprises.
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Worcester Bosch CDi Classic 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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