单选题The purpose of the low pressure cut-out switch is to （）.Amaintain liquid refrigerant at the suction of the compressorBmaintain a preset suction pressure to the compressorCstart and stop the compressor at preset operating pressuresDoperate at minimum efficiency
单选题
The purpose of the low pressure cut-out switch is to （）.
A
maintain liquid refrigerant at the suction of the compressor
B
maintain a preset suction pressure to the compressor
C
start and stop the compressor at preset operating pressures
D
operate at minimum efficiency
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