High
1012 on Worcester Bosch Greenstar 8000 Style

Your boiler has lost its internal connection to the smart controls or sensors, meaning the main computer cannot talk to the rest of the system.

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

No BUS communication

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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