High
1010 on Worcester Bosch Greenstar 4000

Your boiler's electronic control panel is currently unable to send or receive signals, causing the system to stop operating to prevent errors.

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 communication via EMS BUS connection

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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