BoilerFaultCodesYour boiler is trying to light itself but cannot detect a flame, meaning your heating and hot water will likely 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: No flame signal. Following starting procedure the burner starts automatically. After cleaning set the correct gas / air ratio correctly
What causes this fault?
This fault occurs when the boiler's internal computer tries to start the combustion process but cannot confirm that a flame has actually been lit. The most common reasons are a build-up of carbon on the sensing probes or a component failure that prevents gas from flowing correctly into the burner.
This fault is more common during the first few cold spells of autumn, as components that have been idle over summer can struggle to operate or may have become blocked by debris.
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 2950 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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