单选题If the suction pressure at the refrigeration compressor is below normal, the cause can be（）.Arefrigerant overchargeBoverfeeding by the expansion valveCa restricted suction strainerDdue to short cycling of the compressor
单选题
If the suction pressure at the refrigeration compressor is below normal, the cause can be（）.
A
refrigerant overcharge
B
overfeeding by the expansion valve
C
a restricted suction strainer
D
due to short cycling of the compressor
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