BoilerFaultCodesYour boiler has stopped working because of an internal communication error between its electronic control boards.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: LV Wiring Harness. Ensure 8-way PCB connector securely pushed in. If fault persists replace LV wiring harness.
What causes this fault?
This fault occurs when the main control board loses the ability to talk to the ignition system via the internal wiring. It is usually caused by a loose connection at the plug or a physical breakdown in the delicate low-voltage wires over time. Because the components cannot verify they are working together safely, the boiler shuts down as a precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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