单项选择题
A.A shortage of liquid refrigerant
B.Excessive frost on the evaporator
C.Excessive condenser cooling water
D.Insufficient condenser cooling water flow
单项选择题 The general purpose of a heat exchanger is to （）.
单项选择题 The temperature differential occurring between the inlet temperature of the fluid to be cooled and the outlet temperature of the cooling medium in a shell-and-tube heat exchanger is greatest in which of the flow designs listed?（）
单项选择题 The rate of heat transfer between the hot and cold fluids passing through a shell-and-tube type heat exchanger will （）.