High
1-A2 on Worcester Bosch Greenstar 8000 Life

Your boiler has detected an internal communication error between its internal components, meaning it cannot operate safely and has shut itself down.

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

Current fault - Fault code ( table 28)

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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