Carrier 69NT40-541-001, Operation And Service

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T-316 3–2
3.1.3 Evaporator Section
The evaporator section ( Figure 3.2 ) contains the temperature recorder bulb or return recorder sensor, return tempera-
ture sensor, thermostatic expansion valve, dual-speed evaporator fans (EM1 and EM2), evaporator coil and heater,
drain pan heater, defrost heaters, defrost temperature sensor, heat termination thermostat, and heat exchanger.
The evaporator fans circulate air through the container by pulling it in the top of the unit, directing it through the
evaporator coil, where it is heated or cooled, and discharging it at the bottom.
The evaporator components are accessible by removing the upper rear panel (as shown in the illustration) or by
removing the front access panels.
Figure 3.2 Evaporator Section
1. Evaporator Fan Motor #1
2. Return Recorder Sensor
3. Return Temperature Sensor
4. Humidity Sensor
5. Mechanical Recorder Bulb
6. Evaporator Fan Motor #2
7. Defrost Temperature Sensor
8. Heater Termination Thermostat
9. Evaporator Coil
10. Drain Pan Heater 11. Hermetic Thermostatic Expansion Valve
12. Semi-Hermetic Thermostatic Expansion Valve
13. Heat Exchanger
14. Interrogator Connector (Rear)
15. USDA Probe Receptacle PR2
16. USDA Probe Receptacle PR1
17. USDA Probe Receptacle PR3
18. Cargo Probe Receptacle PR4
19. Evaporator Coil Heaters
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HTT Alternate Location
A l t e r n a t e U S D A
Location