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What is the purpose of an alcohol evaporator in an air brake system?
- A.To clean the brake linings while driving
- B.To add alcohol to the fuel for winter starting
- C.To introduce alcohol vapor into the air system to lower the risk of moisture freezing in lines and valves during cold weather
- D.To remove water that has already collected in the tanks
Correct answer
C. To introduce alcohol vapor into the air system to lower the risk of moisture freezing in lines and valves during cold weather
Why
Alcohol mixed with the air stream reduces the chance that condensed moisture will turn to ice inside valves and lines. It is a freezing-prevention aid for winter operation, not a substitute for draining the tanks.
Manual topic: Air Brakes - Alcohol Evaporators · From the Air Brakes practice bank (AB-219).