High
2963 on Worcester Bosch Greenstar 27CDi

Your boiler has detected an incorrect temperature reading, which has caused it to shut down for safety reasons to prevent 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.

Technical description

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

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

2964View →2965View →

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