Question 81 of 140

What is the purpose of the alcohol evaporator found on some air brake systems?

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It puts a small amount of alcohol into the air system to help prevent ice from forming in the valves in cold weather
It removes oil from the fuel system
It cleans the windshield using compressed air pulled from the brake tanks during freezing weather
It powers the air conditioning compressor

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Correct answer to question 81 (Air Brakes): It puts a small amount of alcohol into the air system to help prevent ice from forming in the valves in cold weather

Why

An alcohol evaporator adds alcohol vapor into the air system, which helps lower the freezing point of any moisture in the lines and reduces the risk of ice blocking a valve in cold weather.

Updated: November 2026

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What is the purpose of the alcohol evaporator found on some air brake systems?

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