High
C6 215 on Worcester Bosch Greenstar 12i System

Your boiler has detected that the internal exhaust fan is spinning faster than it should, which is preventing the system from starting 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

Fan problem - Fan running too fast

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

C6View →EAView →

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