单选题An excessive charge of refrigerant in an air-cooled refrigeration system can cause （）.Aoil foaming in the compressorBhigher than normal suction and discharge pressures with a higher box temperatureChigher than normal discharge pressure with a normal box temperatureDthe compressor to run continuously
单选题
An excessive charge of refrigerant in an air-cooled refrigeration system can cause （）.
A
oil foaming in the compressor
B
higher than normal suction and discharge pressures with a higher box temperature
C
higher than normal discharge pressure with a normal box temperature
D
the compressor to run continuously
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