BoilerFaultCodesYour boiler has detected an internal communication error between its main control boards, causing it to stop running for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: GO TO FRAME 73
What causes this fault?
This fault occurs when the boiler's main control board and the display panel stopped talking to each other effectively. It is usually caused by a loose connection in the internal wiring or a mechanical failure within one of the electronic circuit boards. Because the boiler can no longer verify that its settings are correct, it shuts down as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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