MODEL PCA090480WH
CHAPTER 3
TROUBLESHOOTING
Section 2: Troubleshooting Basic System
March 2013
3 - 2
Proprietary/Confidential
Page
69
© 2013 Twist, Inc.
Trouble III:
Abnormally low power draw
PROBABLE CAUSE
SUGGESTED REMEDY
1. Incorrect
compressor
electrical
phasing
1.
Compressor must be re-phased to run in
the correct direction. Changing two-
phase wires in the compressor junction
box can do this.
NOTE:
If the compressor is phased
improperly, the following will
occur:
a. Compressor draws low amperage.
b. Suction and discharge pressures
change very little.
c. Rattling or rumbling sound may be
apparent.
d. Compressor vibrates excessively.
2. Compressor
mechanically
damaged internally
1. Replace
compressor.
1.
Check for proper airflow on supply side of
unit.
3. Low load on the refrigeration
system
2.
Check ambient air temperature to verify if
unit is operating in proper range.
4. Excessive voltage
1.
Check power source.
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