单选题Crankcase sweating in a refrigeration system is caused by （）.Aa stuck solenoid valveBa shortage of refrigerantCtoo much oil in circulationDtoo much superheat
单选题
Crankcase sweating in a refrigeration system is caused by （）.
A
a stuck solenoid valve
B
a shortage of refrigerant
C
too much oil in circulation
D
too much superheat
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