A scrubber fan at a steel tube mill was experiencing increased vibration due to a blockage in the ductwork. FitMachine, an online condition monitoring system, first detected anomalies in the fan's condition and the deterioration continued over several days. When operators inspected they found significant dirt buildup on the fan and in the ductwork. Cleaning the accessible areas allowed the machine to continue running and avoid an unplanned shutdown while a full ductwork clean was scheduled. FitMachine provided cost-effective condition monitoring to support routine vibration surveys and identify the developing issue.