单项选择题
Hot gas bypass is one of the methods used to （）
A.relieve excessive compressor head pressure B.produce flash gas at the expansion valve C.reduce flooding of the receiver at low load D.defrost the evaporator coils
单项选择题 Thermostatic expansion valves can be adjusted for （）
单项选择题 The receiver used in a refrigeration system（）
单项选择题 The purpose of the refrigeration system low pressure cutout switch is to （）
