11 Air Conditioners for Conditioning Air or Other Gases by Heating, Cooling, Humidifying, Dehumidifying, Heat or Moisture Exchange and Cleaning, and Channels and Ducts Enclosed in Such Apparatus; Heat Exchangers-Namely, Hot Air Furnaces, Air Heating and Cooling Coils and Induction Units; Fans, Blowers, Ventilators, Air Grilles, Air Valves, Air Dampers, Air Diffusers, Dry or Wet Filters or Separators; Air Dryers for Lumber, Veneer, Board Sheets, Cellulose, and Other Fibrous Materials, Paper Cardboard, Grain, and Flash-Drying Units, Pulp Drying Units, Utilizing Heat