11 CONDITIONING UNITS, AND PARTS THEREOF, FORCED DRAFT UNIT VENTILATORS OF THE CABINET TYPE, FORCED DRAFT UNIT HEATERS OF THE FLUID-HEATED RADIATOR TYPE, COMPLETE VENTILATING BLOWER UNITS, PROPELLER FANS FOR DIRECT INDUSTRIAL, COMMERCIAL AND INSTITUTIONAL VENTILATION, CENTRIFUGAL FANS FOR HEATING, VENTILATING AND AIR CONDITIONING SYSTEMS, FORCED DRAFT PORTABLE VENTILATORS FOR TEMPORARY VENTILATING PURPOSES