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2--2
T-334
2.1.3 Evaporator Section
The evaporator section (Figure 2--2) contains the return
temperature sensor, humidity sensor, thermostatic
expansion valve, suction modulation valve, dual speed
evaporator fans (EM1 and EM2), evaporator coil and
heaters, defrost temperature sensor, heat termination
thermostat and suction temperature sensor.
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.
Most evaporator components are accessible by
removing the upper rear panel (as shown in the
illustration) or by removing the front access panels.
Components not readily accessible via these locations
are defrost heaters and suction temperature sensor.
18
1
2
3
4
5
6
7
8
9
10
11
12
14
13
15
16
17
WITH
EXPANSION
BYPASS
1. Evaporator Fan Motor #1
2. Return Recorder Sensor/Temperature Sensor
3. Humidity Sensor
4. Evaporator Fan Motor #2
5. Evaporator Coil
6. Evaporator Coil Heaters (Underside of Coil)
7. Heater Termination Thermostat
8. Defrost Temperature Sensor
9. Evaporator Expansion Valve (TXV)
10. Evaporator Expansion Valve Bypass Solenoid
Valve (XBSV)
11. Liquid To Evaporator Expansion Valve
12. To Compressor Suction
13. Evaporator Expansion Valve Bulb
(Under Insulation
14. Interrogator Connector (Rear)
15. USDA Probe Receptacle PR2
16. USDA Probe Receptacle PR1
17. USDA Probe Receptacle PR3
18. Cargo Probe Receptacle PR4
Figure 2--2 Evaporator Section
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