FAQ Search Select a Category Cleaning Formulas Cleaning Tips Corporate Deep Cleaners FAQ Hard Floor Cleaners 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 isn't there any suction with my Pet Grooming Tool? My Garage Pro® blower mode is not functioning. What should I do? The handle on my Momentum or PowerTrak Cyclonic Vacuum is difficult to install. What can I do? My Momentum® or PowerTrak® Cyclonic Vacuum is hard to push. Any suggestions?