Why is it important to drain the air tanks (manually or via automatic drain valves) regularly, especially at the end of each day's driving?

Question

Accepted Answer

To remove water and compressor oil that collect in the bottom of the tank, since the water can freeze in cold weather and cause brake failure

Answer

To reduce the vehicle's overall weight and improve fuel economy

Answer

To reset the governor's cut-in and cut-out pressures

Answer

To test whether the low air pressure warning buzzer is working