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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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单选题A refrigeration system compressor crankcase is sweating or unusually coldThis is an indication of（）.A
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单选题In a refrigeration system, foaming of the crankcase oil may cause the （）.A
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starts after a long idle period
考题
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carbon deposits on the compressor suction valvesB
the evaporator temperature to increaseC
rapid corrosion of the thermal expansion valveD
no operating problems
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