High
258 on Worcester Bosch Greenstar 4000

Your boiler has detected an internal communication error and has safely shut down to prevent potential damage to its electronic components.

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

System fault boiler electronics / basic controller

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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