By Tennessee Hood Cleaners · Updated 2026-10-11
The end of the line
Every bit of grease that passes the filters and duct reaches the fan. The spinning wheel throws grease against the housing, and gravity sends it to the drain and onto the roof.
Effects of a dirty fan
Grease adds weight to the fan wheel and can throw it out of balance. That increases vibration and wear, and reduces how much air the fan can move.
- Reduced airflow at the hood
- Noise and vibration
- Faster belt and bearing wear
- Grease damage to roofing
What helps
Clean the fan with every exhaust cleaning, keep grease containment serviced, and make sure the fan can be opened safely, usually with a hinge kit.