High
2963 B on Worcester Bosch Greenstar 8000 Life System

Your boiler has detected that the temperature reading from its internal pipes is incorrect, so it has safely shut down to prevent potential overheating.

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.

What the manual says

Manufacturer manual

Signal from flow and heat exchanger temperature sensor outside the permissible range

From this model's manual
Verified against the Worcester Bosch Greenstar 8000 Life System installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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

2963View →2964View →

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