High
2963 B on Worcester Bosch Danesmoor

Your boiler has detected that a temperature sensor is not communicating properly, meaning the system cannot safely monitor how hot the water is getting.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 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

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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