单选题Air or noncondensable gas is removed from a refrigeration system by a （）Aseparating chamberBsystem of bafflesCpurge valveDvacuum reducing valve
单选题
Air or noncondensable gas is removed from a refrigeration system by a （）
A
separating chamber
B
system of baffles
C
purge valve
D
vacuum reducing valve
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