单选题Condensate must be drained periodically from the air compressor receivers to prevent （）.Asecond stage cylinder lockupBoil sump contaminationCfaulty operation of pneumatic valvesDcorrosion of air receiver baffles
单选题
Condensate must be drained periodically from the air compressor receivers to prevent （）.
A
second stage cylinder lockup
B
oil sump contamination
C
faulty operation of pneumatic valves
D
corrosion of air receiver baffles
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