单选题Foaming of the oil in a refrigeration compressor crankcase is caused by （）.Arefrigerant boiling out of solution from the lube oilBliquid refrigerant flooding the compressor and systemClube oil viscosity being reduced by refrigerant dilutionDcompressor suction pressure suddenly increasing
单选题
Foaming of the oil in a refrigeration compressor crankcase is caused by （）.
A
refrigerant boiling out of solution from the lube oil
B
liquid refrigerant flooding the compressor and system
C
lube oil viscosity being reduced by refrigerant dilution
D
compressor suction pressure suddenly increasing
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