Below is a list of Exhaust Fans manufacturers from West Chicago, Illinois. Exhaust fans are air blowers that are used to displace gasses from one area to another. While the word “exhaust” is usually associated with gasses produced by industrial processes, all fans that remove a gas from one area and direct it into another are exhaust fans. They are key components of ventilation systems and are usually the last stop in ductwork before the expulsion of air from indoor areas to outdoor areas.