TM 9-4120-378-14
INITIAL SETUP
Test Equipment
Materials/Parts:
150-watt lamp bulb or heat gun
Thermometer (32 F to 212 F)
Equipment Condition:
(0C to 100C)
Front and center covers removed (paragraph 4.17)
Remarks
Action
Location/Item
Disconnect air conditioner power supply
before doing maintenance work on the
electrical system.
Inspect
Inspect for wiring damage.
Rernoval
a. Take out two crews (1) and remove bracket (2)
and thermostat (3) from center cover.
b. Take out two screws (4) and two Iockwashers (5)
and remove thermostat from bracket (2).
c. Tag leads and remove four screws (6) to discon-
nect leads (7, 8, 9, and 10).
See Wiring Diagram,
Test
a. Using a multimeter on the lowest possible set-
fig. FO-2., in Appendix F.
ting, test for continuity between contacts 1 and 2
and between contacts 3 and 4. Contacts should
open on temperature rise at 145-155 degrees F
Use thermometer to determine
temperature of sensor surface.
(63-68 degrees C) and should close on tempera-
ture drop at 100-120 degrees F (38-49 degrees
C). Use 150-watt lamp bulb or heat gun as heat
source for testing.
b. Replace if defective.
Installation
a. Connect leads (7,8,9, and 10) to thermostat (3)
with four screws (6) and remove tags.
b. Attach the thermostat (3) to bracket (2) with two
screws (4) and two Iockwashers (5).
c. Secure the bracket (2) to the center cover with
two screws (1).
See paragraph 4.17.
d. Install front and center covers.
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