(2)  
The APU
 (3)  
The engines
 D.  
A ground cart supplies the conditioned air directly to the mix manifold, and on airplanes with the bypass duct, to the flight deck. The electrical power, pneumatic power, and pack operation are not necessary when you use the ground cart.
 TASK 21-00-00-862-001
 2.  Air Conditioning Pack Operation_______________________________
 A.  General
 (1)  It is recommended that when ambient temperatures are greater than 60 degrees F that conditioned air to cool the airplane on the ground be supplied from a ground conditioned air source, when practical, as an alternative to conditioned air from the air conditioning packs. Refer to 757-SL-21-051 for more data about this maintenance practice.
 CAUTION: DO NOT OPERATE A COOLING PACK AND A GROUND AIR SOURCE AT THE
_______ SAME TIME. THE COOLING PACK CAN NOT CONTROL THE AIR TEMPERATURE IF A GROUND AIR SOURCE IS OPERATED AT THE SAME TIME. YOU CAN CAUSE DAMAGE TO EQUIPMENT IF YOU OPERATE A COOLING PACK AND A GROUND AIR SOURCE AT THE SAME TIME.
 (2)  
Obey this CAUTION during all of this task.
 B.  
References
 (1)  
AMM 06-41-00/201, Fuselage (Major Zones 100 and 200) Access Doors and Panels
 (2)  
AMM 24-22-00/201, Electric Power Control
 (3)  
AMM 36-00-00/201, Pneumatic - General
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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details. 
A
757  
MAINTENANCE MANUAL  
P11 PANEL  
P5 PANEL  
SEE  A 
SEE B 
FLIGHT COMPARTMENT
INOP  INOP  INOP  
FLT DK  FWD CAB  AFT CAB  
AUTO  AUTO  AUTO 
MIX MANIFOLD 
CCC
WWW
OFF OFF OFF 
RECIRC FAN TRIM AIR L R 
ON ONON 
AIRPLANE CHECK 
SKIN VALVE 
OFF INOP INOP 
L PACK R PACK RESET 
RESET 
INOP  INOP 
PACK PACK OFF OFF 
AUTO AUTO OFF 
N S 
N OFF 
FAIRING C 
S 
T 
T BB YY 
W C 
W 
FWD GROUND CONNECTOR
AIR CONDITIONING CONTROL PANEL 
A GROUND CONDITIONED AIR CONNECTOR 
B 
Air Conditioning - General - Maintenance Practices Figure 201 
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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details. 
A
757 MAINTENANCE MANUAL
 C. Operate the Air Conditioning Pack
 S 862-014
 (1) If applicable, disconnect the source of external conditioned air.
 NOTE: If the packs are operated in AUTO when the external
____ conditioned air is used, the cabin temperatures will increase instead of decrease. The temperature sensors in the mix manifold feel the cold air from the ground cart. This causes the packs to increase their exit temperature.
 S 862-002
 (2)  
Start the packs in the AUTO mode.
 (a)  
Supply electrical power (AMM 24-22-00/201).
 (b)  
Supply pneumatic power (AMM 36-00-00/201).
 (c)  
Turn the L and R PACK selectors, on the pilot's overhead panel P5, to the AUTO position.
 (d)  
Make sure the PACK OFF lights go off.
 S 862-003
 (3)  
Start the packs in the STBY mode.
 (a)  
Supply electrical power (AMM 24-22-00/201).
 (b)  
Supply pneumatic power (AMM 36-00-00/201).
 (c)  
Turn the L and R PACK selectors, on the pilot's overhead panel P5, to the STBY-N position.
 (d)  
Make sure the PACK OFF lights go off.
 S 212-006
 (4)  
Make sure the packs are on.
(a) 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址:757 AMM 飞机维护手册 空调 AIR CONDITIONING 1(10)