BoilerFaultCodesYour boiler is struggling to keep a flame lit after it has already started, which prevents it from heating your home properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flame disappears during operation
What causes this fault?
This fault occurs when the boiler's control system loses the signal that a flame is present while it should be running. It is often caused by a dirty or worn-out sensor that can no longer 'see' the flame, or an incorrect mix of gas and air preventing a stable burn. In some cases, recirculating exhaust fumes due to a leaky flue seal can also suffocate the flame shortly after it starts.
This fault can appear more frequently during periods of high wind, as strong gusts can sometimes disrupt the flame stability or affect the pressure within the flue system.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F005 — 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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