BoilerFaultCodesYour boiler has lost its connection to an external safety device or a specific internal link that tells it how to operate safely.
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 electrical connection that bridges the safety circuit on the boiler's control board is broken or missing. It is often caused by a loose wiring connection to your external thermostat, a damaged link plug, or a vibration-induced failure of the circuit board. Without this continuous connection, the boiler shuts down immediately as a safety precaution because it cannot confirm if external controls are allowing it to fire.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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