- Check the upper tank, pre and post-motor filters for debris. Dirty filters can restrict airflow. The filters may be hand washed in cold water with mild detergent, reinstall filters when they are completely dry.
- Failure to properly maintain the filters could result in damage to the motor. A clogged hose may also cause the unit to sound abnormal. Make sure there are no clogs in your vacuum. To check for clogs, review the following: Check for good suction at the end of the upholstery hose. If there is limited suction from the upholstery hose detach the hose from the machine. Insert a broomstick into the hose to push any obstruction through to the opposite end.
-Check the lower hose for clogs. Remove the screw from the left side of the lower hose on the back of the unit and straighten this section of hose by pulling it down or lay unit out flat (the detent will need to be pushed twice) and roll unit on its side with the lower hose towards the top side. Look through the hose for obstructions. Push a broomstick through this lower hose to unclog.
If the machine continues to be loud, please take your machine to a BISSELL Authorized Service Center. To locate your nearest BISSELL Authorized Service Center, go here http://www.bissell.com/support/product-support/service-centers. Enter your zip code to perform your search. You can also locate a Service Center by phone, 24 hours a day, by calling 800-237-7691 and choosing option #1.