1. First, check the pre-motor and the Airetight® HEPA post motor filter for debris. The pre-motor filter is the foam pad in the window marked “filter” behind the dirt-cup. The Airetight® HEPA post motor filter is found below the dirt-cup. Failure to properly maintain the filters could result in damage to the motor. A clogged hose may also cause the unit to sound louder.
2. Check the dirt-cup screen and center tube for debris. Wipe down the screen and the center-tubes (pictured below).Try using a dry cloth first; use a slightly damp cloth if necessary. After wiping, allow time to fully dry.
3. Try adjusting the height setting to ensure it’s correct for the surface you’re cleaning. If the machine is still loud, please take your vacuum to a technician. You can find your nearest BISSELL® Authorized Service Center by clicking http://www.bissell.com/service-centers/ or by calling 1-800-263-2535, available 24 hours a day.