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.
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
21-44-02
ALL ú ú 02 Page 401 ú Feb 10/95
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL
Aft Cargo Temperature Control Switch
Figure 401
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
21-44-02
ALL ú ú 01 Page 402 ú Oct 10/88
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL
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
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
21-44-02
ALL ú ú 02 Page 403 ú Oct 10/91
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL
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.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：747-400 AMM 飞机维护手册 空调 AIR CONDITIONING 1(163)
