单项选择题
A.with the axis of the solenoid horizontal, sensing temperature of the box, and upstream of the thermal expansion valve
B.upright, sensing temperature of the box, and upstream of the thermal expansion valve
C.upright, sensing temperature of the box, and downstream of the thermal expansion valve
D.upright, sensing heat of the tail coil, and upstream of the thermal expansion valve
单项选择题 When a refrigeration compressor is in the ‘off’ cycle, the thermal expansion valve will（）.
单项选择题 To add refrigerant to the high side of an air conditioning system, you should introduce the refrigerant through the （）.
单项选择题 When adding oil to a refrigeration system, precautions must be taken to ensure that （）.