MODEL PCA045480WH
CHAPTER 3
TROUBLESHOOTING
Section 2: Troubleshooting Basic System
3 - 2
March 2013
Page 68
Proprietary/Confidential
© 2013 Twist, Inc.
Trouble II: Excessive
power
draw
PROBABLE CAUSE
SUGGESTED REMEDY
1.
Coils are plugged up. Clear obstruction
in front of condenser coils
2. System
is
over-charged.
3. Liquid
line
filter plugged.
4. Expansion
Valve
failed.
1. High head pressures in
compressor
5.
Compressor is mechanically damaged
internally. Vibration and discolored oil
could accompany this symptom.
1.
Connect supply duct to an aircraft.
2. Blower motor drawing excessive
current due to operation of the
unit while it is not connected to
an aircraft.
2.
If in a test mode, partially block the
aircraft connector or kink hose to
simulate aircraft resistance.
3. Unit operating at low voltage
1.
Stop operations and correct voltage at
source.
4. Single phasing of motors due to
loss of one phase in the power
supply or mechanical connection
of the wiring
1.
Repair connections at all connection
points include locations such as
magnetic contactors.
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