TM 9-4120-404-14
(5) After proper voltages are indicated on all pins of connector, connect it to connector J11 on air conditioner.
(6) Place circuit breaker into ON position.
CAUTION
DO NOT perform the operational check in COOL mode until power has been
supplied to the unit for at least four hours. Liquid refrigerant tends to migrate into
the compressor crankcase and cylinders during periods when the compressor
heater is not operating. Under moderate climatic conditions, the compressor
heater will normally "boil" all liquid refrigerant out within a four hour period. If the
air conditioner has been exposed to below freezing temperatures without power
input, an eight hour warm up period is recommended.
Before starting the air conditioner in COOL mode, make sure that the fabric
condenser cover on the back of the unit is rolled up and secured and that all
screens and guards are in place and unobstructed to avoid damage to equipment.
Table 3-1. Power Voltages for 208 VAC, 3 Phase.
Measure
To Pin
from Pin
A
B
C
D
A
N/A
208
208
120
B
208
N/A
208
120
C
208
208
N/A
120
D
120
120
120
N/A
(7) Turn mode selector switch to COOL and immediately back to OFF.
(8) Observe the condenser fans to determine the direction of rotation.
(9) If fan rotation is from top to bottom, unit power cable is not wired properly. Exchange wires connected to
pins A and B at power source connection and repeat steps (6) and (7) above.
(10) Check unit operation in accordance with paragraphs 2-7 through 2-12.
i. See air conditioner Electrical Schematic Figure 1-5, for additional wiring information.
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