BoilerFaultCodesYour boiler has lit correctly but the flame has gone out unexpectedly, meaning the system 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 loss
What causes this fault?
This fault occurs when the boiler's internal sensor can no longer detect a steady flame after the burner has ignited. The most common reasons include a buildup of carbon on the sensing probe, an inconsistent gas supply, or a component failure that prevents the system from confirming the fire is safely lit.
This fault is more common during extreme cold spells, as freezing temperatures can affect gas pressure or cause the condensate pipe to backup, both of which can extinguish the flame.
DIY fix possible
Check if other gas appliances, like a cooker, are working to ensure gas is reaching the propertyCheck if your gas meter has credit (if using a prepay meter)Press the Reset button on the front of the boiler
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 F2, FN or LN — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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