单选题Excessive oil foaming in the crankcase of a refrigeration compressor at start up can cause（）.Acompressor damage from improper lubricationBrefrigerant absorption by the lubricantCincreased viscosity in the lubricantDcarbon deposit on the compressor suction valves
单选题
Excessive oil foaming in the crankcase of a refrigeration compressor at start up can cause（）.
A
compressor damage from improper lubrication
B
refrigerant absorption by the lubricant
C
increased viscosity in the lubricant
D
carbon deposit on the compressor suction valves
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