Medium
273 C4 on Worcester Bosch Greenstar 12i System

Your boiler has detected that the internal fan is running when it should be idle, often caused by a communication error or a sensor glitch.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Airflow present during last 24 hours

Engineer required

This fault requires 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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