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State Example Questions

C-38 Refrigeration

NOTE: All questions are written and reviewed by licensed contractors who are actively working in the field.

The following questions are typical of the kind of items that are on the examination.

The correct answer is highlighted.


  1. What is the function of a vacuum pump?

    • a. Charge the unit.
    • b. Add oil to the compressors.
    • c. Remove oil from the compressors.
    • d. Remove noncondensible gases from the system.

  2. What are the symptoms of bad valves in a compressor?

    • a. short cycling
    • b. long run cycle
    • c. high suction and low head pressure
    • d. low suction and high head pressure

  3. All of the following are methods of heat transfer EXCEPT:

    • a. conduction
    • b. compression
    • c. convection
    • d. radiation