单项选择题
When a refrigeration compressor motor fails to start, the FIRST thing that should be checked for is a （）.
A.loose expansion valve control bulb
B.low differential setting on the H-Pcutout
C.blown fuse in the motor circuit
D.faulty suction pressure regulator
点击查看答案&解析
相关考题
-
单项选择题
The purpose of the wearing rings used in a centrifugal pump is to （）.
A.prevent an internal explosion in the pump when it is overheated
B.enable a visual inspection of the pump while it is running
C.insure a proper alignment of the pump coupling to the driver
D.accommodate for friction between the impeller and the easing -
单项选择题
The lowest temperature required to cause self-sustained combustion of a substance independent of any outside source of ignition is called （）.
A.explosive range
B.flash point
C.ignition temperature
D.combustion temperature -
单项选择题
If a refrigeration compressor will not start, the reason may be （）.
A.the pressure regulating valve is not closing
B.an excessive lack of refrigerant in the system
C.badly leaking discharge valves
D.worn piston rings
