Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: A Lithium-bromide system is an absorption system that

  • uses ammonia as a refrigerant and lithium bromide as an absorbent
  • uses water as a refrigerant and lithium bromide as an absorbent
  • uses water as a absorbent and lithium bromide as a refrigerant
  • uses salts as an absorbent and lithium bromide as a refrigerant

2: When should a relief valve start to function?

  • Before the purge station discharges
  • Two times it's working pressure
  • 10 psi before it's set pressure
  • At it's set pressure

3: A rule of thumb in air conditioning is ____ CFM per ton?

  • 400
  • 600
  • 100
  • 500

4: Laten heat is associated with a change in state of a refrigerant but not temperature

  • True
  • False

5: Halo-carbon refrigerants cannot be used with what material?

  • Aluminum
  • Stainless Steel
  • Copper
  • Magnesium alloy

6: The most common type of motor starter is

  • duel-winding starter
  • across the line starter
  • part winding starter
  • delts-wye starter

7: A micron is

  • one thousandths of a millimeter
  • one millonths of a centimeter
  • a larger unit of measurement than Hg
  • one millonths of a micrometer

8: Which of the following is NOT a positive displacement compressor?

  • scroll
  • screw
  • reciprocating
  • centrifugal

9: A premise or that portion of a premise where large numbers of people congregate and from which occupants cannot quickly vacate the space such as auditoriums, ballrooms, classrooms, passenger depots, restaurants, and theaters is considered a(n)

  • commercial occupancy
  • illegal occupancy
  • institutional occupancy
  • public assembly occupancy

10: Clearance volume

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

11: Ammonia can come in contact with _______ ?

  • Aluminum
  • Copper tubing
  • Brass
  • Copper

12: The 4 basic methods of determining whether the proper amount of refrigerant is being introduced into the system are

  • sight glass, weight, pressure, and frost line
  • Buss-eye, weight, pressure, and frost line
  • sight glass, weight, pressure, and dipstick
  • sight glass, weight, paper method, and frost line.

13: How do you find net oil pressure on a compressor?

  • discharge pressure - suction pressure
  • gross oil pressure - suction pressure
  • gross oil pressure - discharge pressure
  • all of the above

14: All electrical work done on refrigeration systems must comply with

  • OSHA
  • NEC and Massachusetts Modifications
  • Department of Energy
  • ASHREA-15 Section 9.2.1

15: If a low-pressure chiller has a low-side leak, which of the following will most likely result?

  • High suction pressure and high discharge pressure.
  • Low suction pressure and low discharge pressure
  • Low head pressure and high suction pressure
  • High head pressure and low suction pressure

16: Volts x amps equals

  • Ohms Law
  • Impedance
  • Watts
  • Inductance

17: R-717 is

  • ammonia
  • trichloromethane
  • water
  • carbon dioxide

18: Large vessels containing refrigerant ______________________ from using two or more pressure-relief devices in parallel to obtain the required capacity.

  • containing R-11, R-123 & R-717 exclusively shall not be prohibited
  • of Group B2 refrigerant shall be prohibited
  • shall not be prohibited
  • shall be prohibited

19: All welding done on any refrigeration system or piping covered by 522 CMR 9.00 shall be performed by a according to Section IX of the ASME code

  • licensed technician
  • competent welder
  • welder qualified
  • licensed welder

20: What is used to check very low air pressures in air conditioning duct?

  • Vacuum gauge
  • Barometer
  • Anemomter
  • Manometer

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

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

22: The main purpose of a refrigerant detector in a machinery room is to

  • inform there is a refrigerant leak int he system
  • detect toxins in the air caused by a refrigerant leak
  • to set off an alarm when there is refrigerant present inside the room
  • all of the above

23: A pressure vessel having an inside diameter of 6” or less shall be sufficient to withstand ____times the pressure of the saturation temperature of the refrigerant or ____times the critical pressure of the refrigerant, whichever is less.

  • 6.6, 6.6
  • 2.5, 3.0
  • 2.5, 2.5
  • 3.0, 3.5

24: What is the typical air conditioning operating pressures for 410A?

  • 60 psi suction, 210 psi discharge
  • 25 psi suction, 125 psi discharge
  • 105 psi suction, 350 psi discharge
  • None of the above

25: How much refrigerant can be stored in a mechanical room outside of the system?

  • 150
  • 100
  • 330
  • 200