BoilerFaultCodesYour boiler has lit successfully but then lost its flame while it was running, 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: Loss of flame during operation fault
What causes this fault?
This fault occurs when the boiler successfully starts but cannot maintain a steady flame, causing it to shut down for safety. The most common reasons are a temporary interruption in the gas supply, a dirty flame sensor that can no longer 'see' the fire, or a buildup of debris in the burner area.
This fault is more common in winter, as a frozen external condensate pipe can cause water to back up into the boiler and extinguish the flame.
DIY fix possible
Check that your gas emergency control valve is fully open and you have credit on your meter.Verify if other gas appliances in your home, such as a hob, are working correctly.Gently press the reset button (indicated by a flame with a line through it) to see if the system restarts.
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 F29 — no call-out fees, no surprises.
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