单项选择题
The bulb for the thermal expansion valve is located（）
A.in the middle of evaporator coils B.near the evaporator coil outlet C.near the evaporator coil inlet D.on the bottom row of evaporator coils
单项选择题 The thermal expansion valve responds to the（）
单项选择题 The thermostatic valve has a throttling action, that is to say the valve can（）
单项选择题 When the refrigeration demand is small,（）
