Hello! If the dirt is not entering into the dirt cup this could mean there is a clog in the vacuum or a filter that needs to be cleaned or replaced. Check that the brushes are still spinning. The vacuum has a brush-roll shut-off pedal on the right side of the cleaner if you are standing behind it. Below are simple instructions for checking your vacuum for clogs.
1. Remove the dirt cup. Twist off the dirt cup lid.
2. Remove the filter cartridge from dirt cup.
3. Separate the foam and cartridge filters. Wash foam filter under running. Allow 24 hours to air dry outside the vacuum.
4. Tap the excess dirt out of Hepa filter. Hepa filter may also be washed. Allow 24 hours to air dry.
5. Check the secondary filter by removing the filter cover from base. Rinse the foam filter under running water until it runs clear. Allow 24 hours to air dry.
6. The red baffle tube inside of the dirt cup is apart of the filtration of the vacuum and needs to be cleaned as well. Twist out the baffle tube by turning 1/4 turn clockwise. Remove any hair or debris wrapped around baffle tube. Baffle tube can be rinsed if needed. Allow to dry thoroughly.
7. Remove the hose from both ends. Use a broom stick to loosen and remove any clogs from the main hose.
8. Remove the bottom plate and the brushes as instructed in the owner's manual. Use a wooden spoon or something similar to gently break up and remove any clogs from the lower hose.
9. Inspect the belt for damages, if the belt is broken replace the belt with a Genuine Hoover belt part 562633001 Flat Belt Nano Upright
If the filters are too dirty they may need to be replaced. With regular maintenance the filters should be replaced about once a year. Follow the links below to order replacement filters for your UH20020.
Exhaust Foam Filter
Hope this helps!