(a)  
70B8, FWD CARGO FAN
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SEE A 
GRILL 
(REF) 
WIRE FILTER (REF) 
FORWARD CARGOHEATING INLET TEMPERATURE 
DUCT (REF) 
THERMAL SWITCH 
FORWARD CARGO TEMPERATURE THERMAL SWITCH 
A 
P8 PANEL APU/CARGO FIRE CONTROL PANEL 
APU BTLARMED ARMED DISCH a
FORWARDSEE B 
FWD AFT
CARGO 
r r C
FIRE 
A SWITCH R 
FLT COMPT  OG 
1-BTL DISCH-2 F DISCH APU 
I R 
r E 
DISCH DISCH aa 
APU/CARGO FIRE CONTROL PANEL 
B 
Forward Cargo Compartment Heating Test Components Figure 501 
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 S 865-007
 (4)  
Open these circuit breakers on the main power distribution panel, P6, and attach DO-NOT-CLOSE tags:
 (a)  
6H5, FIRE EXTINGUISHING CARGO BTL 1
 (b)  
6H6, FIRE EXTINGUISHING CARGO BTL 2
 S 215-008
 (5)  
Make sure the FWD CARGO FIRE switch on the aft pilot's control stand, P8, is in the usual position (ARMED light off).
S 715-010
 (6)  
If the ambient temperature in the cargo compartment is less than 50°F (10°C):
 (a)  
Make sure the cargo compartment heating fan operates and pulls air into the inlet.
 S 715-071
 (7)  
If the ambient temperature in the cargo compartment is more than 50°F (10°C):
 (a)  
Use the cooling source to decrease the temperature at the temperature control switch.
 (b)  
Make sure the forward cargo compartment heating fan starts and pulls air into the inlet.
 S 865-011
 (8)  
Remove the DO-NOT-CLOSE tags and close these circuit breakers on the P6 panel:
 (a)  
6H5, FIRE EXTINGUISHING CARGO BTL 1
 (b)  
6H6, FIRE EXTINGUISHING CARGO BTL 2
 S 865-012
 (9)  Remove the electrical power, if it is not necessary
 (AMM 24-22-00/201).
 TASK 21-43-00-735-013
 3. System Test - Forward Cargo Compartment Heating System
______________________________________________________
 A. Equipment
 (1)  
Heating source - hand-held hair blow dryer -commercially available
 (2)  
Cooling source - ice pack - commercially
 available
 (3)  
Thermometer, range 0 to 120°F (0 to 49°C) -commercially available
 B. 
References
 (1)  
AMM 06-46-00/201 Entry Service and Cargo Doors
 (2)  
AMM 24-22-00/201, Electrical Power Control
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 C. Access
 (1)  
Location Zones
 121/122 Forward Cargo Compartment
 211 212 Control Cabin - Section 41
 D. 
Heating System Test
 S 865-014
 (1)  
Supply electrical power (AMM 24-22-00/201).
S 865-015
 (2)  
Make sure these circuit breakers on the pilot's overhead circuit breaker panel, P11, are closed:
 (a)  
11N1, INSTRUMENT AND PANEL AISLE STAND
 (b)  
11N17, CARGO HEATER FAN FWD
 (c)  
11S15, AIR/GND SYS 1