High
6-t2 on Worcester Bosch Greenstar 2000

Your boiler's fan is running continuously even though the heating is not trying to start, which is often caused by a communication error between the internal computer and the fan motor.

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

Permanent fan operation: 0...100% Fan running without gas supply or ignition.

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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