S 014-023
 (2)  Remove the screws that attach the coverplate to the temperature sensor assembly and remove the coverplate.
 NOTE: The temperature sensor assembly is on the left sidewall
____ in the bulk cargo compartment at STA 2010.
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Aft Cargo Temperature Control Switch
Figure 401

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 S 034-027
 (3)
Cut and remove the lockwire from the switch.

 S 034-005

 (4)
Remove the electrical connector from the applicable switch.

 (a)
High temperature switch - DS1979

 (b)
Low temperature switch - DS1988

 S 034-025
 (5)
Remove the nut from the switch.

 S 024-026

 (6)
Remove the switch.

 TASK 21-44-02-404-007
 3. Install the Temperature Control Switch
______________________________________
 A. Standard Tools and Equipment
 (1) Cooling Source (ice pack or equivalent)
 B. References
 (1)
20-11-28/401, Lockwire

 (2)
24-22-00/201, Manual Control

 (3)
36-00-00/201, Pneumatic System

 (4)
IPC 21-43-03 Fig. 1

 (5)
WDM 21-44-11, 21-44-12

 (6)
SSM 21-44-12

 C. Access
 (1)  Location Zone
 145 Bulk Cargo Compartment, LH

 D. Install the Switch
 S 424-008
 (1)
Install the switch with the probe end down.

 S 434-009

 (2)
Install the nut on the bottom side of the switch.

 (3)
Install the lockwire (Ref 20-11-28/401).

 S 434-011

 (4)
Install the electrical connector on the applicable switch.

 (a)
High temperature - DS1979

 (b)
Low temperature - DS1988

 S 434-010
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 S 864-012
 (5)  Close this circuit breaker and remove the DO-NOT-CLOSE tag:
 (a)  P7, Overhead panel
 1) 7H9, CARGO HEAT AFT

 S 864-013
 (6)  
Supply electrical power (Ref 24-22-00/201).

 S 864-014

 (7)  
Supply pneumatic pressure (Ref 36-00-00/201).

 S 864-015

 (8)  
Put the AFT CARGO HT switch on the P5 overhead panel in the ON position.

 S 714-016

 (9)  
Do these steps to do a test of the high temperature switch.

 (a)  Put the CARGO HEAT switch in the up (50 degrees F/10 degrees C) position.
 NOTE: The CARGO HEAT switch is found forward of the bulk cargo
____
 door.

 (b)  If the temperature of the air in the aft cargo compartment is more than 50°F (10°C), do this step: 1) Apply a cool source to the probe end of the high
 temperature switch.
 NOTE: This will decrease the temperature of the switch
____ to less than 50°F (10°C).
 (c)  If the temperature of the air in the aft cargo compartment is more than 80°F (25°C), do this step: 1) Apply a cool source to the overheat switch.
　
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