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单选题
What is the purpose of sub cooling R-12 in the condenser?（）
A
to increase the system efficiency by sensible heat transfer
B
to stop the liquid from flashing
C
to reduce the load on the compressor
D
to remove latent heat of vaporization and the suction piping transfer
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单选题Refrigerant is normally sub-cooled in a refrigeration or air conditioning system condenser to （）.A
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考题
单选题Which of the following may cause that excessively warm water leaves the condenser in a refrigeration plant? （） (1) too little cooling water (2) too much cooling water (3) too warm cooler waterA
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