BoilerFaultCodesYour boiler has detected an internal electrical communication problem between its main control components.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Low voltage wiring harness error
What causes this fault?
This fault occurs when the internal electrical signals between the boiler's control systems and the gas valve are interrupted or lost. The most common reason is a loose connection in the wiring or a degradation of the copper pins within the harness, which prevents the computer from safely controlling the boiler's operation.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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