单选题Refrigerant is normally sub-cooled in a refrigeration or air conditioning system condenser to （）.Amaintain adequate coil back pressureBprohibit flashing in the liquid lineCreduce refrigerant volume in the systemDreduce compressor discharge line loading
单选题
Refrigerant is normally sub-cooled in a refrigeration or air conditioning system condenser to （）.
A
maintain adequate coil back pressure
B
prohibit flashing in the liquid line
C
reduce refrigerant volume in the system
D
reduce compressor discharge line loading
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