单项选择题
A.blue B.green C.orange D.purple
The color of the flame on a halide torch without any re...
单项选择题The color of the flame on a halide torch without any refrigerant present is （）.
If a refrigeration compressor is running continuously w...
单项选择题If a refrigeration compressor is running continuously without lowering temperature as normal in the refrigerator, the trouble may be （）.
A.excessive condenser cooling water B.warm food in the refrigerator C.a shortage of refrigerant D.s shortage of compressor oil
Thermostatic expansion valve are （）.A.either all the wa...
单项选择题Thermostatic expansion valve are （）.
A.either all the way open or all the way closed B.normally open C.throttled depending on load D.controlled by suction pressure
