Head to the auto parts store

The standard way to clean the filter from a kitchen exhaust fan is to stick it in the dishwasher. If that doesn’t get your filter clean, try an auto mechanic’s approach: Buy water-based degreaser at an auto parts store, fill your laundry tub with hot water and degreaser, and let the kitchen filter soak for a few minutes. After that, all it takes is a rinse to clean a range hood kitchen filter. If you want to keep your kitchen clean and grease free, replace your range hood filter every six months.