High
262 & 263 F0 on Worcester Bosch Greenstar 12i System

Your boiler has encountered an internal software or communication error that prevents it from operating safely or correctly.

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

Internal error call Bosch help line 0330 123 3366

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

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