BoilerFaultCodesTechnical 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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