High
C6 on Worcester Bosch Greenstar R29 40 HE

Your boiler has detected that the internal exhaust fan is spinning faster than it should, causing the system to stop working to keep your home safe.

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 speed too low. Check fan lead and connector, and fan; replace as necessary.

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

EAView →F7View →

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