FAQ Search Select a Category BarkBath Cleaning Formulas Cleaning Tips Commercial Products Corporate Deep Cleaners Hard Floor Cleaners Mops, Brooms and Brushes Parts and Accessories Steam Sweepers Vacuums Warranty Web Site and/or go What is the purpose of the Clean Carpet Sensor? Answer: The Clean Carpet Sensor on models #3594 and #3594-M will detect dirt or debris being picked up while vacuuming. The sensor will show red when dirt and debris is being suctioned and will show green when the carpet is clean of debris. Related Questions Why is my vacuum sounding loud? What should I check? Why doesn't my vacuum suction anymore? What should I do if my machine has no power? How do I Install or remove the handle on my PowerGlide® with Lift-Off® Technology?