Even sushi restaurants need their hoods cleaned quarterly, and their hood filters exchanged weekly. The starch molecules in wok cooked rice bond with grease molecules to form a super sticky grease. This grease is heavy and can quickly clog filters, ductwork and exhaust fans. Just by adding this weight to exhaust fan blades can cause electric bills to rise dramatically and shorten the life of belts and the motors themselves. As much as 20 pounds of weight in grease can be added to fan blades in just a few months. This means fans are spinning slower and hotter, using more energy to turn the motor. And the effect compounds itself. Slower turning fan blades move less air, causing more grease to build up on hood filters. Grease buildup on filters means even slower moving air, and more demand on the exhaust fan. Think about the noise your home vacuum makes when the bag is full. This is the same thing an exhaust fan experiences when the blades are loaded with grease and the hood fil
