High
F0 (290) on Worcester Bosch Greenstar 12i System

Your boiler's internal computer is experiencing an error and cannot process signals correctly, which prevents the unit from operating safely.

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

Control box is defective, (Analogue / Digital 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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Related fault codes

E9View →EAView →

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