High
323 A8 on Worcester Bosch Greenstar 12i System

Your boiler is struggling to talk to its internal control system, which means it has stopped working to prevent any potential operating 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

EMS communication error

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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