Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: Copper and its alloys shall not be used with ammonia

  • True
  • False

2: When an A/C system is excessively low on refrigerant

  • it can become contaminated with water
  • there can be nuisance trip outs
  • the suction line may be too hot to touch
  • All of the above

3: pressure relief valves must discharge to the atmosphere at a location not less than 15 feet from ground level and ____ feet from any window, ventilation opening, or exits of buildings.

  • 20
  • 10
  • 15
  • 25

4: A movie theater would be considered a

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

5: The critical temperature of a refrigerant gas occurs when

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

6: Fractionation occurs when

  • some of the blended refrigerant evaporates or condenses before the rest of the blend
  • the pressures decreases as the heat load decreases
  • when a fraction of refrigerant is added as the full charge
  • the pressures increase as the heat load increases

7: _____ alloys shall not be used in contact with an halogenated refrigerants.

  • Nickel
  • Zinc
  • Copper
  • Magnesium

8: A factory-sealed system containing less than 22lbs. of Group A1 refrigerant

  • does not require a pressure-limiting device
  • shall have a pressure limiting device installed on the high side of the system
  • shall be inspected by the Boiler of Inspectors bi-annually
  • shall have a pressure limiting device and a pressure relief valve installed

9: The principle used in continuous type absorption systems is

  • Dalton's Law
  • Ohm's Law
  • Boyle's Law
  • Charles's Law

10: What type of voltage causes the winding in a potential relay to open?

  • BEMF (Back Electro-Motive Force)
  • 24V control voltage from the thermostat
  • 120V line voltage
  • None of the above

11: R-22 is considered a(n)

  • HCFC
  • CFC
  • HCFCH
  • HFC

12: A R-22 system running with a condensing temperature of 110F and a 40F evaporator temperature will read pressures of ____ on the high side and ____ on the low side.

  • 257 psig, 77 psig
  • 226 psig, 68 psig
  • 455 psig, 185 psig
  • 350 psig, 120 psig

13: If the power element on an expansion valve should lose its charge, the valve would

  • Under feed
  • Stay open
  • Close
  • Over feed

14: If a purge unit fails on a low pressure chiller, what are the symptoms?

  • high head pressure
  • increased capacity
  • low pressure chillers do not have purge units
  • low suction pressure

15: Insurance companies shall forward each inspection report of all refrigeration or A/C systems to the Chief of Inspections within

  • 2 months
  • 1 week
  • 30 days
  • 14 days

16: Before you change the type of refrigerant in a refrigeration system, what three things must be done?

  • you can't change refrigerants
  • nothing must be done
  • place sign, check for leaks, insulate
  • make sure it's compatible, notify owner, notify A.H.J

17: Liquid refrigerant R-22 enters an evaporator at 50.2 psig, 20F and leaves 37F, its pressure as it leaves will be

  • 50.2 psig
  • 66.1 psig
  • 43.3 psig
  • 70.8 psig

18: 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

19: How many closing forces operate a thermostatic expansion valve?

  • 3
  • 4
  • 2
  • 1

20: What kind of system uses two different refrigerants in separate systems dependent on each other?

  • Cascade
  • R-414B
  • Low pressure
  • Simple

21: In a properly balanced system with valves open and properly adjusted, if the suction line is warm to the touch, its because of

  • not enough oil in the system
  • oil in evaporator
  • low head pressure
  • moisture in the system

22: What is absolute humidity?

  • the amount of moisture in the air per one pound of 50% RH air
  • the amount of moisture in the air in grains of cubic feet of volume
  • the amount of moisture in the air in grains of square feet of volume
  • none of the above

23: All machine rooms must be outfitted with a detector that _______?

  • activates an audible alarm
  • activates a visual alarm
  • starts the ventilation system
  • All of the above

24: Starting relays for a single phase compressors are used to remove the starting circuit from operation when the motor reaches approximately ____ percent of its speed.

  • 24
  • 75
  • 50
  • 100

25: NH3 is

  • lithium bromide
  • R-718
  • ammonia
  • R-508A