BoilerFaultCodesTechnical 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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