单选题The purpose of the purge valve at the top of the condenser in a refrigerating system is to（）Aremove any air that may accumulate in the systemBtake out unpleasant fumes from the refrigerantCvent off excess refrigerant in an emergencyDpermit opening the refrigerating system for cleaning and inspecting
单选题
The purpose of the purge valve at the top of the condenser in a refrigerating system is to（）
A
remove any air that may accumulate in the system
B
take out unpleasant fumes from the refrigerant
C
vent off excess refrigerant in an emergency
D
permit opening the refrigerating system for cleaning and inspecting
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