Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: A motor is rated for 120 volts and has a RLA (rated-load amps) of 5 amps. What is the wattage of the motor?

  • 600 watts
  • 5KW
  • 1000 watts
  • 746 watts

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

  • Adiabatic
  • Isothermal
  • Pressure Temperature
  • Volume Temperature

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

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

4: Control systems can be classified by

  • safety
  • economy of operation
  • source of power
  • tonnage of system

5: High side floats are used on centrifugal chiller systems are are considered critically charged systems.

  • are obsolete.
  • True
  • depends on the type of refrigerant being used
  • False

6: 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
  • 58F
  • 70F
  • 32F

7: 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

8: Which is the lowest vacuum?

  • 5" hg
  • 1,000 Microns
  • 5 psig
  • 10 psia

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

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

10: A micron is

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

11: What percentage of amperage difference is allowable phase to phase on a HVAC circuit phased to phase?

  • 1%
  • 25%
  • 2%
  • 4%

12: If air is present in an absorption chilled water appliance, which of the following will most likely occur?

  • System operating pressure will drop
  • The Li-Br solution will become more diluted
  • The Li-Br solution will become more concentrated
  • Rust can form

13: Liquid level gauges must be provided with what?

  • Automatic shut-offs
  • A relief valve
  • A low level mark
  • A red line

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

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

15: How many refrigerant classifications are there for toxicity?

  • 1
  • 2
  • 5
  • 3

16: On a single phase motor, when does the start winding cut out?

  • At 25% of its full rated speed
  • At 75% of its full rated speed
  • At 50% of its full rated speed
  • Start windings do no cut-out of the run cycle

17: Which refrigerant is lighter than air?

  • R-717
  • R-123
  • R-11
  • R-134a

18: The generator shell contains the

  • condenser and the absorber
  • condenser, the evaporator, and the generator
  • condenser and the generator
  • evaporator and the absorber

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

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

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

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

21: Class 3 refrigerants are

  • non-toxic
  • highly flammable
  • non-flammable
  • toxic

22: Which occupancy can ammonia be used in?

  • redifential
  • depends on the quantity of freon
  • commercial
  • industrial

23: copper and its alloys shall not be used in contact with _____ except as a component of bronze alloys for bearing or other non-refrigerant containing uses.

  • Lithium bromide
  • HCFC-123
  • ammonia
  • CFC-11

24: What refrigerant is an inorganic compound?

  • R-410A
  • Ammonia
  • R-132A
  • R-22

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

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