单选题In a chilled water air conditioning unit using a reciprocating compressor, the refrigerating effect of the primary refrigerant can be increased by （）.Aincreasing refrigerant pressure in the coilBincreasing chilled water flow through the coolerCsub-cooling the refrigerant in the condenserDsuperheating the refrigerant in the compressor
单选题
In a chilled water air conditioning unit using a reciprocating compressor, the refrigerating effect of the primary refrigerant can be increased by （）.
A
increasing refrigerant pressure in the coil
B
increasing chilled water flow through the cooler
C
sub-cooling the refrigerant in the condenser
D
superheating the refrigerant in the compressor
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