BoilerFaultCodesYour boiler has lost its connection to an external safety device or a control link, causing it to stop running as a precaution.
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 loop that connects the boiler's internal safety circuit is broken, often due to a loose connection or a faulty overheat thermostat. If this link is interrupted, the boiler immediately shuts down because it can no longer verify that it is operating within safe temperature limits. It is frequently caused by a vibration-loosened wire or a component that has tripped to prevent the system from overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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