MODEL PCA090480WH
CHAPTER 2
SERVICE
Section 3: Refrigeration Basics and Service
March 2013
2-3
Proprietary/Confidential
Page 41
© 2013 Twist, Inc.
B.
Service
Valves
Schrader type valves are used on the PCA unit.
The Schrader type valve is for convenient checking of system pressures
or charging refrigerant without disturbing the unit’s operation. An
adapter is necessary for the standard service gauge or hose connection
to fit the Schrader type valve.
The valves are located on the compressor piping leading to each
compressor. Once connections are made, ensure that all service doors
are closed as much as possible to allow proper airflow through the
condenser coils.
C.
Removing
Refrigerant
Occasionally it will be necessary to remove the refrigerant from a
system. This may be required in order to repair leaks or make other
repairs. If a system has been overcharged, it may be necessary to
remove the excess charge to insure proper system operation.
EPA Regulations prohibit venting refrigerant into the atmosphere.
Always use a refrigerant recovery system. Check the instructions on
the recovery system for proper operation and follow the latest EPA
Regulations for refrigerant disposal and records. Check the oil level in
the compressor crankcase after the refrigerant is removed.
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