High
2963 B on Worcester Bosch Hideaway

Your boiler has detected an unusual temperature reading because a sensor wire is faulty or has come loose, causing the system to shut down for safety.

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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Related fault codes

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