Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: If the dry bulb temperature is 85F and the wet bulb temperature is 70F, the dew point temperature will be approximately (use psychometric chart)

  • 58F
  • 70F
  • 32F
  • 77F

2: The test pressure applied to the high side of each factory-assembled refrigerating system shall be at least equal to the design pressure of

  • 2.5 times the design pressure
  • the aggregate of the high side and low side
  • the high side
  • the low side

3: The purpose of a receiver is

  • a vessel to store refrigerant outside the system
  • to increase the capacity that the system can hold
  • to use a a later date
  • all of the above

4: The pressure relief device of a positive displacement compressor shall discharge in the ______________or in accordance with 9.7.8

  • high side of the system
  • low side of the system
  • the liquid side of the system
  • the vapor side of the system

5: What is the temperature that a liquid and a vapor can exist in equilibrium called?

  • Dry bulb temperature
  • Critical temperature
  • Saturated temperature
  • Wet bulb temperature

6: Can ammonia be used on domestic system?

  • no, unless there is proper ventilation system installed
  • yes
  • yes, for systems under 10 tons
  • no

7: What is the state of the refrigerant leaving the evaporator?

  • low temperature superheated vapor
  • a low temperature subcooled liquid
  • a high temperature superheated vapor
  • a high temperature subcooled liquid

8: What is the boiling point of refrigerant governed by?

  • P&T relationship
  • Compressor RPM's
  • Condenser sub-cooling
  • Evaporator temperature

9: Pressure vessel having an inside diameter exceeding 6” with an internal pressure greater than 15psig shall be marked directly on or on the nameplate the letters _______________ signifying compliance with the ASME Boiler & Pressure Vessel Code.

  • “U” or “UM”
  • “UV”
  • “UM” and “UV”
  • “UL”

10: R-123 belongs to Group

  • B-1
  • B-2
  • A-3
  • B-3

11: How would you know if there was a loss of crankcase pressure?

  • oil will foam
  • oil level will rise
  • oil will thin out
  • oil will thicken

12: Megaohm meter's main function is

  • to detect weak motor winding insulation of a refrigeration or air conditioning compressor by creating high DC voltages to the compressor
  • to detect very high resistances to ground of refrigeration or air conditioning compressors
  • to test very high value capacitors for large 3-phase refrigeration compressors and blower motors.
  • Both a and b are correct

13: Dual-pressure relief devices should be installed on

  • vessels of 10 cubic feet or less
  • vessels of 10 cubic feet or more
  • vessels of 3 cubic feet or less
  • vessels of 3 cubic feet or more

14: In a properly balanced system with valves open and properly adjusted, if the suction line is warm to the touch, its because of

  • low head pressure
  • oil in evaporator
  • not enough oil in the system
  • moisture in the system

15: Which refrigerant was still able to be vented to the atmosphere after July 1, 1992?

  • R-22
  • R-113
  • R-11
  • R-12

16: A 24 volt transformer with a 240 volt primary can handle how many amps?

  • 20 amps
  • 10 amps
  • 24 amps
  • There isn't enough information to answer.

17: Industrial occupancy is

  • a premise or that portion of a premise that is not open to the public, where access by authorized persons is controlled, and that is used to manufacture, process, or store goods, such as chemicals, food, ice, meat, or petroleum.
  • is a premise or that portion of a premise where large number of people congregate and from which occupants cannot quickly vacate the space.
  • a premise or that portion of a premise where people transact business, receive personal service, or purchase food and other goods.
  • Both a and b are correct

18: Refrigerant systems containing Group I refrigerants can be installed in or on public stairways.

  • True
  • False

19: When using nitrogen for brazing, the pressure should be:

  • 125 psig
  • 50-100 psig
  • Slightly below atmospheric
  • Very low

20: Which of the following is an inorganic refrigerant?

  • R-22
  • Ammonia
  • Chlorofluorocarbons
  • All of the above

21: Which winding have the most turns?

  • Start
  • run
  • they have equal amount of turns
  • depends on the motor phase

22: Most CFC's are

  • inert but toxic
  • toxic
  • flammable
  • inert

23: The level of voltage caused by back electromagnetic force that opens the contacts of a potential relay in order to take the start capacitor out of the circuit is

  • pick-up voltage
  • lift voltage
  • run voltage
  • boost voltage

24: The color code of a tank of ammonia is

  • silver
  • lavender
  • light green
  • white

25: A water regulating valve opens when

  • the compressor is on
  • when the power is on
  • when the power is on there is an overcharge of refrigerant
  • the head pressure rises