Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: A crankcase heater has a supplied voltage of 100 volts and is drawing 1.4 amps. What is the resistance?

  • 104 ohms
  • 80 ohms
  • 71 ohms
  • 27 ohms

2: One ton of refrigeration is defined as ______ btu/minute.

  • 12,000
  • 60
  • 720,000
  • 200

3: When must refrigeration system covered by the code be inspected?

  • Annually and when installed
  • Not required
  • Annually
  • Upon installation

4: 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

5: What will occur if the strong solution in an absorption chiller becomes too strong?

  • The machine will cool excessively as the solution crystallizes.
  • The machine will stop cooling and the solution will evaporate.
  • The machine will stop cooling and solution will crystallize
  • The machine will cool excessively as the solution evaporates

6: A hissing noise at the expansion valve is a good indication that

  • gas is passing thru it
  • nothing is passing thru
  • liquid is passing thru it
  • expansion valve is oversized

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

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

8: It takes how many BTU's of latent heat/hr to boil 1 lbs of water into steam?

  • 24,000 BTU
  • 12,000 BTU
  • 144 BTU
  • 970 BTU

9: What refrigerant doesn't have to be classified?

  • R-422A
  • R-718
  • R-717
  • R-134A

10: The amount of heat required to raise the temperature of 1 lb of water 1F is?

  • 1 Therm
  • The rate of conduction
  • 1 Kelvin
  • 1 BTU

11: What is the purpose of a surge capacitor on a contactor?

  • to provide smoother start/stops
  • to protect low voltage equipment
  • to balance the sine waves
  • to keep the contactor pulled in

12: A secondary coolant is defined as

  • a low temperature refrigerant used for cascading systems
  • any refrigerant direcly in contact with the cooling space for process cooling
  • any liquid used for the transmission of heat without a change of state in A/C refrigeration systems having flash point above 150F
  • a combination of interconnected parts from a closed circuit in where fluid is circulated for the purpose of cooling for a refrigeration system.

13: If air is present in an absorption chilled water appliance, which of the following will most likely occur?

  • The Li-Br solution will become more diluted
  • Rust can form
  • System operating pressure will drop
  • The Li-Br solution will become more concentrated

14: All low-pressure chillers use which type of compressor?

  • Reciprocating
  • Centrifugal
  • Rotary
  • Scroll

15: Large mercantile occupancy is

  • a premise of that portion of a premise where more than 50 persons congregate on levels above of below street level to purchase personal merchandise.
  • a premise or that portion of a premise where more than 1500 persons congregate on levels above or below street level to purchase personal merchandise
  • a premise of that portion of a premise where more than 100 persons congregate on levels above of below street level to purchase personal merchandise.
  • a premise or that portion of a premise where more than 200 persons congregate on levels above or below street level to purchase personal merchandise

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

  • R-12
  • R-113
  • R-22
  • R-11

17: Two capacitors are wired in parallel. One capacitor has a value of 15uf. The other has a value of 25uf. What is the total value supplied?

  • 20 uf
  • 40 uf
  • 15 uf
  • 25 uf

18: Two systems using separate refrigerants that are superimposed upon one another is called

  • indirect
  • cascade
  • single stage
  • booster

19: Class 3 refrigerants are

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

20: While the system is operating, the discharge line should be

  • at the same temperature as the crankcase
  • 10-15F warmer than ambient
  • too hot to hold by hand
  • room temperature

21: 1 HP = ____ Watts?

  • 3,412
  • 746
  • 11,239
  • 3.1416

22: Fractionation occurs when

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

23: Pressure vessels with an internal volume of 10 cubic feet or more

  • shall use rupture discs or duel pressure relief valves
  • shall use pressure relief devices or fusible plugs
  • shall use pressure relief devices
  • shall use fusible plugs

24: What is a megaohm meter?

  • An electric meter used by electricians to test large 3-phase blower motors for the correct rotation
  • Is an electric meter that measures extremely low resistance valves by sending high DC voltage signal into the object being tested.
  • An electric meter that measures very high resistance values by sending a high DC voltage signal into the object being tested
  • An electric meter that measures very high resistance values by sending a low voltage AC signal into the object being tested

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

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