CDL · Air brakes
What is the purpose of an alcohol evaporator in an air brake system?
Correct answer: To keep ice from forming inside the brake system.
Answer options
- ATo keep ice from forming inside the brake system Correct
- BTo help the tires grip slippery roads
- CTo cool the brakes on long downhill grades
Why
The evaporator adds alcohol to the air supply so that moisture is less likely to freeze in the valves and lines when it is cold; ice inside the system can block the air and keep the brakes from working. It does nothing for tire grip or brake cooling.
About this question
Topic: Air brakes License: CDL
Part of these practice sets:
Where it applies: Asked in every state.
Practice the whole set
This question is part of How Air Brakes Work (18 questions). Take the full set and check your score.
Practice How Air Brakes WorkMore questions from How Air Brakes Work
- Which part of the vehicle drives the air compressor?
- Air brakes are really several braking systems combined. Which of these is NOT one of them?
- If the air compressor springs a leak, which valve keeps the stored air from escaping?
- On a vehicle with air brakes, what do the brake shoes and linings press against each time you brake?
- In an air brake system, what is the purpose of the air storage tanks?
- On an air brake system, what pressure does it normally take for the safety valve to open?
- Air-braked trucks and buses most often use which kind of brake at the wheels?
- Your air brake system's safety relief valve starts letting air escape. What does this tell you?
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