High
1012 on Worcester Bosch Greenstar 2000

Your boiler's internal components are having trouble communicating with the main control board, similar to a computer losing its connection to a keyboard.

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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Related fault codes

1013View →212View →

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