BoilerFaultCodesYour boiler started to heat up but the flame went out unexpectedly, causing the system to stop working.
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. The most common reason is a dirty or worn sensor that can no longer 'see' the flame, or a blockage in the condensate trap that causes water to back up and extinguish the burner.
This fault is more frequent during very cold snaps, as freezing temperatures can block the external drain pipe, causing water to back up into the boiler and put the flame out.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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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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