TM 9-4120-371-14
TABLE 4-1. UNIT PREVENTIVE MAINTENANCE
CHECKS AND SERVICES (PMCS) (cont.)
Item
Item To Be
Procedures
No.
Inspected/Serviced
NOTE
The temperature control thermostat has an effective
functional range between 40F and 90F (5C
and 32C). In extreme conditions when ambient air
temperature is below 40F (5C) or above 90F
(32C), operation in either LO HEAT or HI HEAT
mode will vary from that described above.
1. Turn Temperature control thermostat knob to fully
INCREASE (clockwise) position, then turn mode selector
start immediately and that compressor starts approximately
30 seconds later. Hold your hand in airflow from condensed
air outlet grille; there should be no change in temperature.
Now turn Temperature control thermostat knob to fully
DECREASE (counter clockwise) position and feel outlet
air temperature begin to drop almost immediately. Leave
controls in present position and perform next check.
m.
After 15 minutes of operation check the sight glass and
compare refrigerant condition with the color coded
n. Turn mode selector switch to OFF and observe that all air
conditioner functions cease.
o. Set-up the air conditioner for the desired operational mode.
p. Record performance of quarterly PMCS, including all
corrective actions taken.
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