TM 5-4120-361-14 low  speed  (1800  RPM). Due to possible thermal lag, the changeover may be slow to react when the ambient temperature drops below the 100°F (38°C) changeover point. 1-7. Difference Between Models. This manual covers the following two models. (1) AAF Model CH436-1 ates on 208-volt, 3-phase, power (2) AAF Model CH636-1 ates on 208-volt, 3-phase, ac power which oper- 400-Hertz  ac which oper- 50-60  Hertz In this manual, difference in models is identified by reference to the opera- ting frequency, that is, either as the 400-Hertz model or the 60-Hertz model. 1-8. Performance  Data. The following listing contains the performance and dimensional data appli- cable to the air conditioner. (1) Air conditioner, models CH436-1 and  CH636-1: Nomenclature . . . . Air  conditioner, horizontal,  compact Manufacturer . . . . Capacity: Cooling . . . . Heating: High . . . . Low . . . . Ventilation.  . Phase . . . . Hertz . . . . AC volts . . . . American Air Filter  Co.,  Inc. 36,000  BTU/hr 35,600  BTU/hr. 20,400  BTU/hr. 1285  CFM 3 400  (Model CH436-1) 50/60  (Model CH636-1) 208 Current input, full load, amperes Cooling . . . . 28.5 High heat . . . . 31 Low heat . . . . 15.5 Ventilating. . . . 3.2 Refrigerant. . . . R22 (2)  Dimensions  and  weights: Length  .  .  .  . 34.8  in. (88.4 cm) Height  .  .  .  . 27.0  in. (68.6 cm) Width .  .  .  . 38.0  in. (96.5  cm) Weight  .  .  .  . 435 lbs (198 kg) Section III. TECHNICAL PRINCIPLES OF OPERATION 1-9. Refer to paragraphs 1-5 and 1-6 various controls available to the opera- for a description of the functions per- ter. Refer to figure 1-4 for the elec- formed by the air conditioner and iden- tical schematic and figure 1-5 for the tification of the components that per- wiring diagram of the air conditioner form the various functions. Refer  to electrical   system. paragraph 2-2 for a description of the Index, Figures 1-4 and 1-5. ELEC REF PART NUMBER DESCRIPTION DESIG B1 D13216E6309 COMPRESSOR B2 D13216E6140 MOTOR, CONDENSER FAN B3 D13216E6451 MOTOR, EVAPORATOR FAN B4 D13216E6140 MOTOR, CONDENSER FAN 1-4