BoilerFaultCodesYour boiler is struggling to keep its flame lit during operation, which is causing it to stop and restart frequently.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: No flame signal. With low output the burner starts automatically after cleaning. If the fault occurs repeatedly, the setting of the CO2 valves need checking
What causes this fault?
This fault occurs when the boiler's internal sensors lose track of the flame while it is firing at a low power level. It is usually caused by a dirty or worn flame sensor that can no longer 'see' the fire, or a gas valve that isn't delivering the precise amount of fuel needed to maintain a stable small flame.
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 2948 B — 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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