Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: Direct systems using Group II refrigerants

  • shall not be used for air condition for human comfort
  • shall be allowed to be used for human comfort.
  • shall be installed in Class T machinery rooms
  • shall be installed per instruction of the AHJ

2: 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
  • not enough oil in the system
  • moisture in the system
  • oil in evaporator

3: Absolute pressure is

  • Gauge Pressure
  • Atmospheric Pressure
  • Gauge + Atmospheric Pressure + Pi
  • none of the above

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

  • true
  • false

5: What must be done to all doors and access points in duct work going through a mechanical room?

  • Must be hindged
  • Must be screwed shut
  • Must be sealed and gasketed
  • All of the above

6: When a refrigerating machinery room is used, the emergency procedures shall be posted

  • on a conspicuous card located near the evaporator
  • on a conspicuous card located near the compressor
  • outside the room, immediately adjacent to each door
  • inside the room, immediately adjacent to each door

7: 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.

  • 100
  • 250
  • 400
  • 350

8: Brazed joints melt at temperatures above

  • 1,000F
  • 800F
  • 1,200F
  • 500F

9: What happens to copper joints when overheated?

  • nothing
  • joint becomes oxidized and ditorted
  • copper becomes harder
  • none of the above

10: What instrument is used to measure very high resistance?

  • ammeter
  • voltmeter
  • tape measure
  • meg ohmmeter

11: What would be the classification of a church?

  • Place of assembly
  • Industrial
  • Large mercantile
  • Institutional

12: Lithium-bromide, Li-Br, is best characterized as a

  • sugar
  • soil
  • salt
  • sand

13: Three-phase motors have what type of windings?

  • three run windings
  • one start winding and one run winding.
  • three run windings and 3 start windings
  • three start windings

14: An azeotropic refrigerant is

  • a mixture of two or more refrigerants that boil at about the same temperature minimizing temperature glide.
  • a mixture of two or more refrigerants that boil at much different temperatures causing temperature glide
  • a mixture of two or more refrigerants that boil at much different temperatures minimizing temperature glide
  • none of the above

15: Indirect systems using Group II refrigerants

  • shall be used in refrigeration system less than 1,000 lbs
  • shall be used in refrigeration system in excess of 1,000 lbs
  • shall have all refrigerant containing parts except piping, installed in a Class T machine room
  • shall be used for mechanical equipment only

16: What device should be used on low-temperature freezers?

  • discharge muffler
  • high capacity TXV
  • oil separator
  • hot-gas by-pass

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

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

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

  • nothing must be done
  • place sign, check for leaks, insulate
  • make sure it's compatible, notify owner, notify A.H.J
  • you can't change refrigerants

19: The equivalent length of pipe in a water piping system is

  • the total length of pipe plus equivalent of fittings multiplied by 2.31
  • the total length of pipe as you would measure it plus 25% for fittigns
  • the total length of pipe as you would measure it
  • the total length of pipe plus equivalent-length of fittings

20: The amount of heat required to raise the temperature of 1 lb of water 1F is?

  • 1 Kelvin
  • 1 BTU
  • The rate of conduction
  • 1 Therm

21: System design pressures must take into consideration, not only, pressures found during normal operation but also what?

  • When it's cold out
  • When there is a malfunction on the high side
  • When its warm out
  • All of the above

22: RPM's of a centrifugal compressor are at approximately?

  • 500
  • 10,000
  • 15,000
  • 30,000

23: Refrigerants shall be classified by

  • requirements for commercial, industrial, and residential occupancies
  • toxicity and flammability
  • maximum permissible quantities of each group
  • color codes

24: 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)?

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

25: Which of the following types of oils are hygroscopic?

  • polyolester (POE)
  • polyalkylene glycol (PAG)
  • naphthene mineral
  • both a and b