BoilerFaultCodesYour boiler has detected a software or communication error on the main control board, which is preventing the system from operating correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: All Boilers
What causes this fault?
This fault occurs when the boiler's internal computer, the main circuit board, suffers a software crash or loses connection with other components. It is often caused by a sudden electrical surge, loose internal wiring, or simply the electronic components failing due to age. Because the 'brain' of the boiler can no longer process data correctly, it shuts the system down for safety.
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 301 — 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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