BoilerFaultCodesYour boiler has lost its connection to an essential safety internal plug, meaning it currently cannot communicate correctly with its control system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Jumper 8-9 not detected.
What causes this fault?
This fault occurs when the boiler's control board loses its physical connection to a specific internal safety plug that identifies how the unit should operate. The most common reason is that the plug has vibrated loose over time, sustained moisture damage, or the internal wiring harness has developed a fault. Without this connection, the boiler shuts down immediately as a safety precaution because it no longer recognizes its own configuration.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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