Emergency
C1 on Worcester Bosch Greenstar CDi Compact

Your boiler has detected that the internal fan responsible for clearing exhaust gases has stopped working, so it has safely shut itself down to prevent carbon monoxide buildup.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Airflow stopped during operation

Engineer required

This is a emergency 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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