High
C6 215 on Worcester Bosch Junior 24i

Your boiler has switched itself off because the internal fan is spinning at the wrong speed, meaning it can't safely clear away waste gases.

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 →

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