High
259 on Worcester Bosch Greenstar 28CDi

Your boiler's computer is struggling to read internal electronic signals, which has caused it to stop working to ensure safety.

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

AD reference 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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