BoilerFaultCodesYour boiler has lost its flame while running and cannot restart, likely because it is not getting enough gas or the ignition system 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: Flame extinguished re-ignition unsuccesful | Gas supply absent or insufficient
What causes this fault?
This fault occurs when the boiler successfully starts but the flame goes out unexpectedly while it is trying to heat your home. The most common reasons are a temporary interruption in your gas supply, a buildup of carbon on the sensing probes, or a failing gas valve that can no longer maintain a steady flow. Essentially, the boiler's safety system steps in because it can no longer detect the heat of a consistent flame.
This fault is more frequent during extreme cold snaps, as sub-zero temperatures can cause external gas regulators to freeze or lead to a drop in local gas pressure.
DIY fix possible
Check that your gas emergency control valve is in the 'on' positionIf you have a prepayment meter, ensure you have sufficient creditTry to reset the boiler by pressing the flame/cross button to see if it reignites
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 F.29 — no call-out fees, no surprises.
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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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