Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: What is the purpose of a trap in a vertical discharge line with an upward flow?

  • start the flow of oil throughout the system
  • ensure proper oil return to the compressor
  • Installing a vertical discharge line with an upward flow is prohibited by code
  • None of the above

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

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

3: An electrical circuit has a 208V power supply and draws 47 amps total, What would be the wattage of the circuit

  • .9776 watts
  • 977.6 watts
  • 9.776 watts
  • 9,776 watts

4: What is R-290’s max design pressures for high and low sides?

  • 250psig high side and 125psig low side
  • 450psig high side and 200psig low side
  • 210psig high side and 110psig low side
  • 300psig high side and 150psig low side

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

  • nozzle
  • baffle
  • suction
  • volute

6: Liquid shall not occupy more than ____ of the volume when the temperature of the refrigerant is 90F.

  • 90%
  • 100%
  • 75%
  • 80%

7: What does ANSI stand for?

  • American National Standards Institute
  • American National Safety Institute
  • When a technician becomes a bit “ansi” when having an issue troubleshooting a system
  • None of the above

8: A solder joint melts at temperatures of

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

9: Which of the following is NOT a positive displacement compressor?

  • centrifugal
  • screw
  • scroll
  • reciprocating

10: Pressure vessel having an inside diameter exceeding 6” with an internal pressure greater than 15psig shall be marked directly on or on the nameplate the letters _______________ signifying compliance with the ASME Boiler & Pressure Vessel Code.

  • “UV”
  • “UL”
  • “U” or “UM”
  • “UM” and “UV”

11: The 4 basic methods of determining whether the proper amount of refrigerant is being introduced into the system are

  • sight glass, weight, pressure, and dipstick
  • Buss-eye, weight, pressure, and frost line
  • sight glass, weight, paper method, and frost line.
  • sight glass, weight, pressure, and frost line

12: An example of an "Expendable Refrigerant" is

  • lithium bromide
  • liquid nitrogen
  • ammonia
  • liquid oxygen

13: Usually dry bulb temperature is

  • same as wet bulb temperature
  • higher than wet bulb temperature
  • lower than dry bulb temperature
  • not important and shall be ignored

14: A direct system

  • is one which encloses a separate body of evaporative refrigerant
  • is a self-contained complete factory made and tested system
  • is where the refrigerant comes in contact with the space refrigerated
  • is on where brine is cooled & circulated to the space refrigerated

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

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

16: What type of voltage cause a potential relay to open?

  • 24 volt supply from the thermostat
  • 120 volt line voltage
  • Pick-up voltage
  • none of the above

17: What should not (and can not) be located between a pressure imposing device and a pressure-limiting device?

  • Muffler
  • Stop valve
  • Moisture indicator
  • Foot valve

18: Large vessels containing refrigerant ______________________ from using two or more pressure-relief devices in parallel to obtain the required capacity.

  • shall not be prohibited
  • containing R-11, R-123 & R-717 exclusively shall not be prohibited
  • shall be prohibited
  • of Group B2 refrigerant shall be prohibited

19: If two 500 ohm resistors are connected in series, the resistance will be

  • 1000 ohms
  • 20 ohms
  • 500 ohms
  • 200 ohms

20: The first step in mechanical refrigeration is

  • evaporation
  • condensation
  • expansion
  • compression

21: On an air cooled condenser, if the ambient air is 35F and dropping, what's its effect to the condensor?

  • it would make the condenser less efficient
  • it would cause the condenser to sweat
  • it would make the condenser more efficient
  • it would have no effect on the condenser

22: How many different groups of refrigerants are there?

  • 11
  • 7
  • 3
  • 15

23: A VRF system is a direct system

  • true
  • false

24: If you have a motor of 2 HP or less and under 300V, you can use a single pole switch (snap switch) with at least what rating? 

  • 1x FLA
  • 5x FLA
  • 4x FLA
  • 2x FLA

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

  • CPR valve
  • EEV
  • Solenoid valve
  • EPR valve