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)

  • 77F
  • 70F
  • 32F
  • 58F

2: The boiling point of a refrigerant is based on

  • Temperature
  • Heat content
  • a pressure-temperature relationship
  • None of the above.

3: Heat cannot of itself, pass from a

  • cold to a warmer body
  • warm to a colder body
  • state of hot energy to a state of cold energy
  • None of the above

4: An example of an "Expendable Refrigerant" is

  • liquid nitrogen
  • ammonia
  • lithium bromide
  • liquid oxygen

5: Can you use Ammonia in industrial applications?

  • Yes, Under certain condidtions
  • No, never
  • When mixed with R-718
  • Yes, always

6: R-22 is classified as a ____ refrigerant on the safety matrix.

  • A-1
  • B-2
  • A-2
  • B-1

7: A motor starter contains a thermal overload and a

  • contactor
  • solenoid
  • transformer
  • 3-way relay

8: What must be done to refrigerant pipes before being buried ?(8.10.4)

  • Classifed
  • Certified
  • Leak checked
  • Insulated and installed in a pipe duct (Encased)

9: What is considered a cooling agent?

  • any liquid used for the transmission of heat when condensation occur
  • any liquid used for the transmission of heat without condensation
  • any liquid used for the transmission of heat when vaporization occurs
  • any liquid used for the transmission of heat without vaporization

10: On a centrifugal compressor, stationary diffuser vanes are needed to

  • stop gas flow
  • prevent high pressure on the packing
  • convert velocity energy to pressure
  • increase the clearance space

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

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

12: Large Mercantile occupancy is a premise or that portion of a premise where more than ____ persons congregate on levels above or below the street level to purchase personal merchandise.

  • 350
  • 100
  • 400
  • 250

13: One atmosphere equals

  • 0 psia
  • 14.7
  • 0 psig
  • 29.4

14: Gauge pressure is

  • Force of pressure above that of atmosphere
  • Absolute pressrue
  • Atmospheric pressure
  • Barometric pressure

15: On a ammonia compressor, the pressure of a forced fed oil pump is changed by varying the

  • cooling temperature set-point
  • adjustment of the spring tension of the TXV
  • opening at the pump inlet
  • opening at the pump outlet

16: Before you change the type of refrigerant in a refrigeration system, what three things must be done?

  • Make sure its compatible, notify owner, and notify AHJ.
  • you can never change refrigerants
  • Nothing must be done
  • Place sign, check for leaks, and insulate suction line

17: A thermometer inside a duct measures ____ heat.

  • latent
  • specific
  • hidden
  • sensible

18: R22 and 410A operate at the same range of condensing and evaporating temperatures

  • true
  • false

19: The main purpose of the accumulator is to

  • prevent liquid slugs at the compressor
  • store liquid refrigerant
  • provide space for the accumulation of oil and containminants
  • provide space for vapor to accumulate

20: Refrigerant is metered into the evaporator on a large centrifugal chiller thru the

  • low side of the system
  • high side float assembly
  • cap tube
  • none of the above

21: A solder joint melts at temperatures of

  • 1,200F to 1,500F
  • less than 400F
  • 400F to 800F
  • 600F to 900F

22: What is the maximum voltage range allowed on an electrical circuit?

  • 20%
  • 5%
  • 10%
  • 15%

23: Pressure-limiting device isn't required on a factory-sealed system containing less than ____ lbs.

  • 18
  • 22
  • 50
  • 33

24: Increasing superheat will do what to your frost line?

  • Decrease
  • Increasae
  • Could either increase or decrease depending on the load conditions
  • Nothing

25: If a purge unit fails on a low pressure chiller, what are the symptoms?

  • high head pressure
  • increased capacity
  • low suction pressure
  • low pressure chillers do not have purge units