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MODEL PCA090480WH
CHAPTER 3
TROUBLESHOOTING
Section 5: Helpful Troubleshooting information
March 2013
3-5
Proprietary/Confidential
Page
91
© 2013 Twist, Inc.
A.
Low current draw - you can expect about half of the normal operating
amperage.
B.
Suction and discharge pressures will change very little and will be about
equal.
C.
After a long running time (up to 30 minutes of running backwards) the
motor winding thermostat opens due to excessive heat.
D.
Compressor makes a lot of noise.
E.
Compressor
vibrates.
U
WARNING
U
: RUNNING THE COMPRESSOR BACKWARDS WILL
DAMAGE THE COMPRESSOR IF RUN FOR AN
EXTENDED PERIOD OF TIME. ALWAYS ENSURE
THAT THE COMPRESSOR IS RUNNING PROPERLY
AFTER MAKING REPAIRS OR REPLACEMENTS.
11.
Compressor Operating in a Vacuum
U
CAUTION:
U
OPERATING THE SCROLL COMPRESSOR IN A
VACUUM WILL RESULT IN ELECTRICAL OR
MECHANICAL DAMAGE TO THE COMPRESSOR.
The scroll compressor can pull into a vacuum much quicker than a
reciprocating compressor. There are two failures that will occur due to running
the compressor in a vacuum:
A.
Fusite failures - The fusite terminals will arc internally which results in a
motor failure.
B.
Scroll galling – This occurs due to no or a very low flow of refrigerant.
This is most likely to occur if the compressor is run into a vacuum. It
happens because there is no flow, and the discharge temperature is in
the range of 400-500°F, which causes the orbiting scroll to rub on the
fixed scroll, resulting in a compressor failure. The failure will start to
initiate in 1-2 minutes of operation and will only deteriorate further after
the failure starts.
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