Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: The oil separator is always inserted in the system

  • in the discharge line
  • where it can be easily serviced
  • in a cool spot
  • to prevent oil logging

2: A compressor in which the increase in vapor pressure is attained without changing the internal volume of the compression chamber is called

  • non-volumetric displacement compressor
  • neutral chamber-type compressor
  • non-positive displacement compressor
  • negative displacement compressor

3: Control systems can be classified by

  • source of power
  • economy of operation
  • tonnage of system
  • safety

4: Group A3 refrigerants have a ______ flammability rating than Group B1 refrigerants

  • higher
  • the same
  • lower
  • there is no Group B1 refrigerants

5: The location of the thermal bulb for the TXV on the evaporator effects

  • both the pressure and temperature in the feeler bulb
  • the amount of superheat required to operate the TXV
  • the amount of liquid in the evaporator
  • the amount of gas in the evaporator

6: Start to Run windings will have what resistance?

  • The least resistance value
  • The most resistance value
  • Somewhere between the actual start winding and run winding resistance value
  • All will be at equal values

7: Usually dry bulb temperature is

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

8: The gauge thickness required on a CO2 tank construction is

  • 3/32"
  • 1/16"
  • 5/16"
  • 1/8"

9: The main purpose of the accumulator is to

  • provide space for vapor to accumulate
  • prevent liquid slugs at the compressor
  • provide space for the accumulation of oil and containminants
  • store liquid refrigerant

10: How many refrigerant classifications are there for flammability?

  • 2
  • 1
  • 3
  • 7

11: "E" references ____ in the Ohm's law formula

  • amperage
  • voltage
  • resistance
  • capacitance

12: Where is an EPR valve located on a multi-evaporator system?

  • Suction line of the warmest evaporator
  • Suction line prior to the accumulator of the lowest temperature system
  • Suction line at the compressor
  • Suction line of the coolest evaporator

13: How many square inches per square foot?

  • 64
  • 24
  • 98
  • 144

14: How can you test mechanical strength of an electrical connection?

  • measure ohms with an electrical meter
  • measure voltage across the connection
  • attempt to pull the wire from the connector by hand
  • none of the above.

15: R22 and 410A operate at the same range of condensing and evaporating temperatures

  • true
  • false

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

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

17: Oils, classified as to source, are

  • naphthalene, paraffin, and castor
  • naphthalene, mixed, and paraffin
  • animal, vegetable, and mineral
  • animal, vegetable, and castor

18: Low pressure chiller systems use what type of compressor?

  • Screw
  • Scroll
  • Centrifugal
  • Reciprocating

19: The critical temperature of a refrigerant gas occurs when

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

20: What is a megaohm meter?

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

21: The equivalent length of pipe in a water piping system is

  • the total length of pipe plus equivalent-length of fittings
  • the total length of pipe as you would measure it plus 25% for fittigns
  • the total length of pipe as you would measure it
  • the total length of pipe plus equivalent of fittings multiplied by 2.31

22: What do you need to do when you install a new system?

  • Add refrigerant
  • Insulate the suction line before you take a superheat reading
  • Document the superheat and subcooling reading
  • Have it inspected

23: 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 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 1500 persons congregate on levels above or 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

24: Excessive head pressure is often caused by

  • thermostat set too high
  • air cooled condenser is plugged
  • insufficient refrigerant
  • leaking reed valve on the discharge side

25: Which winding have the most turns?

  • they have equal amount of turns
  • depends on the motor phase
  • run
  • Start