Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: Ammonia systems use ____ pressure to adjust oil pressure

  • stream
  • liquid
  • discharge
  • air

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

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

3: On a 460V motor, what is he MAXIMUM voltage that can be safely applied to it?

  • 506v
  • 550v
  • 660v
  • None of the above

4: Liquid refrigerant flashing, or turning to vapor, in the liquid line may be due to

  • liquid line that is too small
  • shortage of refrigerant
  • liquid line that had too high vertical lift
  • All of the above

5: The level of voltage caused by back electromagnetic force that opens the contacts of a potential relay in order to take the start capacitor out of the circuit is

  • run voltage
  • pick up voltage
  • lift voltage
  • boost voltage

6: The critical temperature of a refrigerant gas occurs when

  • any decrease in pressure will cause condensation
  • the gas returns to a liquid
  • any increase in pressure will not liquefy the gas
  • the gas is no longer saturated

7: Systems containing more than 110 pounds must have stop valves located at the

  • compressor suction inlet
  • compressor discharge outlet
  • receiver inlet and outlet
  • All of the above

8: 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
  • centrifugal switch
  • printed circuit board (PCB)
  • duel-voltage switch

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

  • Barometer
  • Vacuum gauge
  • Manometer
  • Anemomter

10: Doors communicating with outside from a mechanical room must be?

  • Steel, approved, weather-stripped
  • Self-closing, aligned, fire door
  • Self-closing, approved, fire door
  • Self-closing, wooden, fire door

11: The location of the thermal bulb for the TXV on the evaporator effects

  • both the pressure and temperature in the feeler bulb
  • the amount of superheat required to operate the TXV
  • the amount of liquid in the evaporator
  • the amount of gas in the evaporator

12: 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

13: One ton of refrigeration is defined as ______ btu/minute.

  • 200
  • 60
  • 720,000
  • 12,000

14: A premise where large numbers of people congregate and from which occupants can not quickly vacate the space is considered

  • commercial occupancy
  • public assembly occupancy
  • institutional occupancy
  • mixed occupancy

15: What is a megaohm meter?

  • An electric meter that measures very high resistance values by sending a high DC voltage signal into the object being tested
  • An electric meter that measures very high resistance values by sending a low voltage AC signal into the object being tested
  • An electric meter used by electricians to test large 3-phase blower motors for the correct rotation
  • Is an electric meter that measures extremely low resistance valves by sending high DC voltage signal into the object being tested.

16: When releasing a hydrogenated hydrocarbon refrigerant to the atmosphere, ample ventilation must be provided and

  • no flames shall be permitted
  • explosion precautions must be taken
  • gas masks must be worn
  • the owner shall be informed

17: Ammonia belongs to Group

  • B-2
  • A-2
  • B-1
  • A-1

18: Ammonia can come in contact with _______ ?

  • Brass
  • Aluminum
  • Copper tubing
  • Copper

19: "E" represents _____ in the Watt's law formula.

  • reactance
  • watts
  • voltage
  • amperage

20: What is Trichlorotrifluoromethane?

  • R-12
  • R-113
  • R-13
  • R-11

21: A 24 volt transformer with a 240 volt primary can handle how many amps?

  • 24 amps
  • 20 amps
  • 10 amps
  • There isn't enough information to answer.

22: Name a reason that does not cause reduced condenser air quantity

  • High ambient temperature
  • Dirty fan blades
  • Dirty Coil
  • Prevailing winds

23: Thermodynamics is the branch of science that deals with

  • energy due to motion
  • molecular therory
  • heat energy
  • state of energy

24: On a day with low relative humidity, the two thermometers on a sling psychrometer will read

  • nearly the same
  • 2F difference
  • a ling psychrometer doesn't have two theremometers.
  • far apart or greater difference

25: Single compound Refrigerants are classified by what two criteria?

  • Temperature range and hazardousness
  • Flammability and toxicity
  • Weight and color
  • Flammability and temperature range