System PartsQuestion 4 of 60
Why do air storage tanks have a drain valve at the bottom?
a.To add oil to the compressed air
b.To increase the air pressure faster
c.To connect the trailer air lines
d.To remove water and compressor oil that collect inside
Explanation
Compressed air contains some water and compressor oil that collect at the bottom of the tanks. This buildup can freeze in cold weather and damage the brakes, so tanks have drain valves to remove it. Tanks without automatic drains must be drained manually, often at the end of each driving day.
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