Fan Reduced Airflow Due to Lack of Bearing Lubrication

This is the most likely cause when the fan exhibits a squealing or grinding noise combined with a sluggish start. To confirm, unplug the device and manually rotate the fan blades; significant resistance or a lack of smooth, silent spin indicates that the motor bearings have lost their lubrication. Persistent grinding suggests the internal shaft bearings are dry and experiencing metal-on-metal friction.

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