Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: An example of direct system is

  • rooftop unit
  • chiller
  • absorber
  • none of the above

2: What is the purpose of suction/discharge traps?

  • to ensure proper oil return to the compressor
  • to keep oil inside the evaporator for proper oil return to the compressor
  • to keep oil inside of the accumulator for proper return to the compressor
  • all of the above

3: What is absolute humidity?

  • the amount of moisture in the air per one pound of 50% RH air
  • the amount of moisture in the air in grains of cubic feet of volume
  • the amount of moisture in the air in grains of square feet of volume
  • none of the above

4: Viscosity is

  • the ability of oil to flow
  • measure of weight
  • a measure of heat content
  • the coefficient of external friction

5: What is not a requirement of a Class T machine room?

  • Tight fitting doors
  • Self-closing doors
  • Fire hose connected to the building fire protection system.
  • Automatic ventilation

6: A pressure-limiting device isn't required on a factory-sealed system containing less than ____ lbs.

  • 50
  • 66
  • 22
  • 25

7: What device removes the start winding from the circuit of a split-phase motor once the motor reaches 75% of its rated load amps (RLA)?

  • duel-voltage switch
  • motor starter
  • centrifugal switch
  • printed circuit board (PCB)

8: Heat transferred by conduction from one body to another is done

  • via liquids
  • via heat rays
  • via solids
  • via radiation

9: How many CFMs are required per square foot of commercial office occupied space

  • 15 CFM
  • 20 CFM
  • 5 CFM
  • .5 CFM

10: Ammonia systems use ____ pressure to adjust oil pressure

  • liquid
  • air
  • discharge
  • stream

11: B3 refrigerants are considered

  • toxic and highly flammable
  • non-toxic but non-flammable
  • toxic but non-flammable
  • non-toxic but flammable

12: Clearance volume

  • is the same on all compressors
  • affects compressor capacity
  • has no effect on compressor capacity
  • varies depending on compressor speed

13: While the system is operating, the discharge line should be

  • 10-15F warmer than ambient
  • room temperature
  • too hot to hold by hand
  • at the same temperature as the crankcase

14: How many groups of refrigerants are there?

  • 1
  • 7
  • 3
  • 5

15: The actual expansion curve of compression follows most nearly which one of the following curves?

  • Pressure Temperature
  • Isothermal
  • Adiabatic
  • Volume Temperature

16: In a horizontal shell & tube condenser, the ammonia is liquefied by

  • water sprayed over condenser
  • passing thru the tubes from top to bottom
  • removing the latent heat of fusion
  • removing the latent heat of vaporization

17: In an air conditioning plant which an indirect low side, water is used inside of bring: the proper sequence of operating the plan is

  • reset the expansion valve
  • start the fan and circulating pump
  • start the comrpessor
  • reset the safety valve

18: Ammonia is under what safety classification?

  • B3
  • A3
  • B2
  • B1

19: A 120 volt motor rated at 1,800 watts. You find the motor is drawings 25 amps. The motor is

  • drawing RLA and is running as it should
  • drawing LRA and is seized and should be replaced.
  • running hot
  • none of the above

20: Name a CFC refrigerant(s):

  • R-11
  • R-12
  • R-123
  • both a & b

21: If the power element of an expansion valve should lose its charge the valve would

  • underfeed the evaporator
  • overfeed the evaporator
  • go open
  • go closed

22: On an air cooled condenser, if the ambient air is 35F and dropping, what's its effect to the condensor?

  • it would cause the condenser to sweat
  • it would make the condenser less efficient
  • it would make the condenser more efficient
  • it would have no effect on the condenser

23: At higher altitudes, boiling temperatures

  • depends on the refrigerant
  • are unaffected
  • decrease
  • increase

24: Fusible plugs shall not be used with pressure vessels of

  • 3 cubic feet or more
  • 15 cubic feet or more
  • 3 cubic feet or less
  • 15 square feet or less

25: One atmosphere equals

  • 0 psig
  • 29.4
  • 0 psia
  • 14.7