High
290 F0 on Worcester Bosch Greenstar 12i System

Your boiler's internal computer is struggling to read its own sensors, which has caused it to shut down for safety to prevent incorrect heating operations.

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 converter 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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