单项选择题
A feeler or thermal bulb is used for the expansion valve to （）.
A.detect the temperature B.detect the pressure C.heat the refrigerant D.accelerate the refrigerant
单项选择题 The expansion valve on a Freon system controls the （）.
单项选择题 During working, thermostatic expansion valve should be （）.
单项选择题 When the temperature of the refrigerant flowing out from the condenser is below the condensing temperature, it is said to be （）.
