Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: Which of the following is an example of an azeotropic refrigerant?

  • R-410A
  • R-404A
  • R-500
  • R-134A

2: Brazed joints melt at temperatures above

  • 500F
  • 1,200F
  • 1,000F
  • 800F

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

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

4: Which refrigerant was still able to be vented to the atmosphere after July 1, 1992?

  • R-22
  • R-11
  • R-12
  • R-113

5: 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

6: 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

7: Color is important in oil because

  • it indicates the viscoisty.
  • can tell us something about the refining of oil
  • it makes sight glasses easy to read
  • allows you to see into crankcase

8: What does safe access mean?

  • Locked doors
  • A clear unobstructed path to the equipment and controls
  • Well-lit exit signs
  • OSHA approved

9: Can ammonia be used on domestic system?

  • yes
  • no, unless there is proper ventilation system installed
  • no
  • yes, for systems under 10 tons

10: When can recovered refrigerants be reused?

  • They can't
  • Only when used in original owner's equipment
  • Only if used in 30 days of recovery
  • None of the above

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

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

12: Crankcase heaters are energized

  • to prevent compressor freeze-up
  • while the compressor is running
  • when the compressor is off
  • to allow easy compressor start-up

13: Where would the EPR valve be located on a multiple evaporator system?

  • outlet of high temperature evaporator
  • outlet of the liquid line
  • inlet of the low temperature evaporator.
  • outlet of low temperature evaporator

14: Before replacing a seized compressor, the _______ should be determinded.

  • type of refrigerant
  • designed head pressure
  • cause of seizure
  • current draw

15: Transformers are rated in

  • volts
  • amps
  • volt-amps
  • volts-ohms

16: Suction valve unloaders afford an effective means of

  • evaporator control
  • capacity control
  • superheat control
  • refrigerant control

17: How far from the window does a relief valve need to be according to ASHRAE-15?

  • There is no minimum for relief valve and windows.
  • At least 20'
  • At least 40'
  • At least 30'

18: What measures gas pressure?

  • Manometer
  • Hygrometer
  • Barometer
  • Hydrometer

19: The location of a thermal bulb of a TXV affects

  • subcooling
  • the amount of liquid in the condenser.
  • the amount of liquid returning to the compressor
  • the amount of liquid refrigerant in the evaporator

20: 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

21: Low ambient controls are used when

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

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

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

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

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

24: If a halide torch is used for leak detection, what color is the flame if it detects a leak?

  • blue
  • red
  • green
  • orange

25: The first step in mechanical refrigeration is

  • evaporation
  • condensation
  • expansion
  • compression