High
1021 on Worcester Bosch Greenstar 8000 Life System

Your boiler is struggling to accurately measure the temperature of the water it is heating, so it has safely shut down 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

Hot water temperature sensor is defective

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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