Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: An electronic bridge circuit is basically a

  • high voltage circuit
  • Wheatstone
  • 24 volt control circuit
  • suspension

2: If the dry bulb temperature is 85F and the wet bulb temperature is 70F, the dew point temperature will be approximately (use psychometric chart)

  • 32F
  • 70F
  • 58F
  • 77F

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

  • R-12
  • R-113
  • R-22
  • R-11

5: Halogen refrigerants are corrosive to which type of metal?

  • magnesium
  • stainless steel
  • black iron
  • copper

6: It shall be the duty of the person in charge of the premises on which a refrigeration system containing more than ___ lbs of refrigerant is installed to provide a schematic drawing or panel giving directions for the operation of the system.

  • 50
  • 55
  • 75
  • 15

7: The outer portion of shell of the compressor used on low-pressure chillers is called the

  • baffle
  • nozzle
  • suction
  • volute

8: Joints in piping for refrigeration containing parts must withstand temperatures of ___?

  • 600F
  • 800F
  • 1000F
  • 700F

9: A low oil switch is typically

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

10: How do you find net oil pressure on a compressor?

  • discharge pressure - suction pressure
  • gross oil pressure - suction pressure
  • gross oil pressure - discharge pressure
  • all of the above

11: A normally operating R-410A system with a condensing temperature of 110F will have a high side pressure of around ______ psig

  • 327 psig
  • 125 psig
  • 255 psig
  • 365 psig

12: R-717 is

  • water
  • trichloromethane
  • carbon dioxide
  • ammonia

13: 14.7 psia is equivalent to

  • atmospheric pressure at seal level
  • 29.92" Hg
  • 0 psig
  • All of the above.

14: What measures gas pressure?

  • Hydrometer
  • Manometer
  • Barometer
  • Hygrometer

15: A multi-evaporator refrigeration system uses what type of valve to maintain evaporating temperatures?

  • CPR valve
  • Solenoid valve
  • EPR valve
  • EEV

16: Cooling tower lowers condenser water temp by

  • running water thru a secondary heat exchanger
  • running fans at 100%
  • evaporative cooling
  • condensation

17: How many gallons of water do you need per pound of ammonia?

  • 50
  • 10
  • 1
  • 100

18: On a single phase motor, when does the start winding cut out?

  • 100% of its RLA speed
  • 25% of its RLA speed
  • 75% of its RLA speed
  • 50% of its RLA speed

19: What is the typical air conditioning operating pressures for R-22?

  • 60 psi suction 210 psi discharge
  • 25 psi suction 125 psi discharge
  • 105 psi suction 340 psi discharge
  • None of the above

20: When testing systems using non-positive displacement compressors, the entire system shall be considered for test purposes as the low side.

  • True
  • False

21: In an air conditioning system, the unit of total heat energy content in an air/vapor mixture is

  • Sensible heat
  • Latent heat
  • Enthalpy
  • Specific heat

22: On a ammonia compressor, the pressure of a forced fed oil pump is changed by varying the

  • adjustment of the spring tension of the TXV
  • cooling temperature set-point
  • opening at the pump inlet
  • opening at the pump outlet

23: The best way to detect ammonia in brine is

  • potassium of line
  • nessler regaent
  • carbonation of soda
  • CO2 gas

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

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

25: Refrigerant restricted in 2004 but used for transition for decades:

  • R-134A
  • R-123
  • R-22
  • R-11