MODEL PCA090480WH
CHAPTER 3
TROUBLESHOOTING
Section 4: Troubleshooting Refrigeration System
3-4
March 2013
Page 74
Proprietary/Confidential
© 2013 Twist, Inc.
Trouble I:
Compressor fails to start (continued)
PROBABLE CAUSE
SUGGESTED REMEDY
1.
Check for sufficient refrigeration charge
in system.
5.
Suction pressure below cut-out
setting of low pressure switch
2.
Check system for refrigeration leaks.
1.
Reset pressure switch.
2.
Check refrigeration system for proper
charge.
6. Discharge pressure above cut-
out setting of high pressure
switch
3.
Check condenser airflow.
7. Excessively low voltage
1.
Correct at power source.
8. Controller
not
operating
properly 1.
Check controller for proper operations
and replace if necessary.
Trouble II:
Compressor short cycles or shuts off after a few minutes of operation
PROBABLE CAUSE
SUGGESTED REMEDY
1. Intermittent connections in
electrical system
1.
Check for loose connections in the
electrical system. Tighten all
connections.
2. Evaporator coil frosted or frozen,
causing low suction pressure
1.
See “Evaporator Coil(s) Freeze Up”
Chapter 3-5 page 6.
3. Excessive
head
pressure,
causing high pressure switch to
open
1.
See “Refrigerant Discharge Pressure too
High” Chapter 3-5 page 10.
4.
Faulty compressor motor 1.
Replace
compressor.
5. Low supply airflow
1.
Check for kinks in the duct and clean air
filters. See Section 3-3 Trouble #1 for
additional information.
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