Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: Joints in refrigeration piping must be _____ before being covered?

  • Leak tested
  • Pressurized
  • Inspected
  • Insulated

2: What is the temperature that a liquid and a vapor can exist in equilibrium called?

  • Saturated temperature
  • Wet bulb temperature
  • Critical temperature
  • Dry bulb temperature

3: Pressure vessels with an internal volume of 3 cubic feet or less

  • shall use pressure relief devices
  • shall use fusible plugs
  • shall use pressure relief devices or fusible plugs
  • do not need pressure relief protection

4: A hissing noise at the expansion valve is a good indication that

  • expansion valve is oversized
  • liquid is passing thru it
  • nothing is passing thru
  • gas is passing thru it

5: "R" represents ___ in the Ohm's law formula

  • voltage
  • capacitance
  • resistance
  • amperage

6: The rupture disc on a low-pressure chiller typically releases pressure at

  • 10 psig
  • 0 psig
  • 15 psig
  • 5 psig

7: The total amount of refrigerant stored in a machinery room in all containers not provided with relief valves shall not exceed

  • 660 lbs
  • 330 lbs
  • 500 lbs
  • 55 lbs

8: The actual expansion curve of compressor follows most nearly which one of the following

  • Pressure-Temperature
  • Adiabatic
  • Volume
  • Isothermal

9: 1 Watt = ______ BTU's?

  • 4.482
  • 3.412
  • 7.216
  • 12

10: Which of the following is a drop-in for R-22

  • R-410A
  • R-134A
  • R407C
  • None of the above

11: With a 5/8" X 5/8" x 3/4" tee, what size is the center connection?

  • 1/2"
  • 5/8"
  • 3/8"
  • 3/4"

12: Total heat of a substance is considered

  • empathetical
  • sensible heat
  • specific heat
  • enthalpy

13: The first step in mechanical refrigeration is

  • expansion
  • evaporation
  • compression
  • condensation

14: A micron is

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

15: When is the only time you can leave a service container attached to a system?

  • Leaking system
  • Recovery
  • Charging
  • Both b and c

16: Low ambient controls are used when

  • on air conditioning systems only
  • always
  • economizers are used
  • when systems run all year round

17: What type of refrigerants are NOT flammable?

  • CHC
  • HFC
  • HCFC
  • All of the above

18: In an A/C unit, dirty filters will cause

  • high discharge pressure
  • high suction pressur
  • low oil pressure
  • low suction pressure

19: In a low temperature refrigeration system, the benefit of the system using P.A.G. oil is

  • it is hydroscopic
  • it traps moisture
  • viscosity
  • all of the above

20: What type of pressure relief device is used on a CO2 system?

  • Glove valve
  • Fusible plug
  • Rupture disk
  • Gate valve

21: 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

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

  • 4%
  • 1%
  • 25%
  • 2%

23: A low oil switch is typically

  • non used on semi-hermetic compressors over 10 ton capacity
  • automatic reset
  • time-delay auto reset
  • manual reset

24: Which refrigerant is lighter than air?

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

25: A EPR valve is installed on what type of evaporators?

  • low-temperature evaporators
  • shell and tube evaporators
  • high-temperature evaporators
  • plate evaporators