Air tank drains:

Question

Compressed air in an air brake system usually contains a certain amount of water and compressor oil. The water and oil can damage the brakes if left to accumulate in the system. Manually operated air tank drains must be opened daily to remove this build-up.

Accepted Answer

Are used to drain water and oil from an air tank.

Answer

Allow rain water to enter an air tank.

Answer

Should never be opened.

Answer

Must remain open during driving.