BoilerFaultCodesYour boiler is struggling to keep a flame lit and has safely shut down after several failed attempts to stay running.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flame signal lost 5 times in 4 minutes
What causes this fault?
This fault occurs when the boiler detects a flame but cannot maintain it, leading to the system cutting the gas supply for safety. The most common reasons are a dirty or worn flame sensor that can no longer 'see' the fire, or an unstable gas flow that causes the flame to flicker and go out. It typically indicates that while the boiler can start, it isn't receiving the steady fuel or signal needed to stay running.
This fault can be more frequent in winter as increased demand on the local gas network or cold weather affecting external regulators can lead to the fluctuations in gas pressure that cause flame loss.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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