单项选择题
A.a shortage of compressor oil B.warm food in the refrigerator C.excessive condenser cooling water D.a shortage of refrigerant
A.molecular fluid vibration B.energy losses C.wide pressure variations D.mechanical damage to control valves
A.Keeps the refrigerated space cooler B.Reduces the efficiency of the plant C.Takes the load off the compressor D.Has no affect on the system