Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: 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

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

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

3: Capacity control on a centrifugal compressor is accomplished by the

  • check valves
  • pre-rotational guide vanes
  • post-rotational guide vanes
  • slide vanes

4: A solder joint melts at temperatures of

  • 1,200F to 1,500F
  • 400F to 800F
  • less than 400F
  • 600F to 900F

5: What is not a requirement of a class T machine room?

  • automatic ventilation
  • tight fitting doors
  • fire hose connection to the building fire protection system
  • self-closing doors

6: Which refrigerant is lighter than air?

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

7: How are a compressor and condenser fan wired?

  • series-parallel
  • series
  • parallel-series
  • parallel

8: What effect does the temperature of air have on humidity?

  • warmer air holds more moisture then cooler air
  • cooler air holds more moisture then warmer air
  • air has no effect of humidity
  • none of the above

9: When can 50/50 solder be used?

  • in the low side
  • in the high side
  • liquid and suction lines
  • none of the above.

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

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

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

  • ammeter
  • meg ohmmeter
  • tape measure
  • voltmeter

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

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

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

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

14: The start winding has _____ turns than the run winding.

  • more
  • less
  • the same
  • none of the above

15: Halogenated refrigerants cannot be used with what material?

  • Aluminum
  • Magnesium alloy
  • Stainless steel
  • Copper

16: The density of a gas refers to

  • pounds per cubic foot
  • cubic feet per pound
  • pounds per square foot
  • pounds per absolute pressure

17: Class 3 refrigerants are

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

18: At higher altitudes, the boiling point of refrigerant is

  • the same
  • higher
  • equal to the coefficient of water at 32F
  • lower

19: If your suction line is warmer than the room temperature, this may indicate

  • below normal superheat
  • plugged air filter
  • an over charge
  • a low charge

20: The first step in mechanical refrigeration is

  • evaporation
  • compression
  • expansion
  • condensation

21: A motor starter is a device that includes an overload and a _______?

  • contactor
  • 2-pole contacts
  • duel-coil
  • all of the above

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

  • Insulated
  • Pressurized
  • Inspected
  • Leak tested

23: Which of the following most closely represents the concentration of Li-Br in a absorption system?

  • 50% Li-Br, 50% tap water
  • 40% Li-Br, 60% distilled water
  • 40% Li-Br, 60% tap water
  • 60% Li-Br, 40% distilled water

24: One atmosphere equals

  • 0 psia
  • 14.7
  • 29.4
  • 0 psig

25: A total of all group A-2,B-2, A-3, and B-3 refrigerants shall not exceed ____ lb in the occupied areas and machinery rooms of institutional occupancies.

  • 50
  • 350
  • 550
  • 100