BoilerFaultCodesYour boiler has experienced a serious internal electronic failure and has shut down to ensure safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner blocked, burner control unit fault or internal fault
What causes this fault?
This fault occurs when the boiler's internal computer can no longer communicate with the components that control the flame and safety sensors. It is usually caused by a critical component failure on the main circuit board or a loose connection within the internal wiring that prevents the system from performing its safety checks. Because the boiler cannot confirm the burner is operating safely, it shuts down entirely to prevent any risk.
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 FF — no call-out fees, no surprises.
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