单选题When a refrigeration compressor motor fails to start, the FIRST thing that should be checked for is a （）.Aloose expansion valve control bulbBlow differential setting on the H-PcutoutCblown fuse in the motor circuitDfaulty suction pressure regulator
单选题
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
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