BoilerFaultCodesYour boiler's internal computer has encountered a critical error and cannot communicate with the rest of the system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Printed circuit board (PCB) Fault
What causes this fault?
This fault occurs when the boiler's central control board suffers an internal hardware failure or loses the ability to send signals to other components. It is often caused by a surge in the electrical supply, moisture ingress, or simply the natural degradation of the solder joints and microprocessors over time. The system shuts down as a safety precaution because it can no longer monitor the boiler's operation accurately.
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 F9 — 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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