BoilerFaultCodesYour boiler has detected an unusual temperature reading because a sensor or its wiring is not communicating correctly with the main control unit.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Signal from flow and heat exchanger temperature sensor outside the permissible range – the connecting lead needs connecting correctly
What causes this fault?
This fault occurs when the boiler's central control board receives an impossible temperature reading from the internal sensors. This is usually caused by a loose connection in the internal wiring or a sensor that has physically failed, meaning the boiler can no longer safely monitor the water temperature inside the heat exchanger.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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