Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: What is potential measured in?

  • Ohms
  • Henrys
  • Volts
  • Amps

2: No open flames are allowed in the machinery room unless?

  • Approved by the installing contractor
  • Approved by the authorized person
  • Only when combustion air is provided from outside of the machinery room
  • Never can be allowed

3: How many closing forces operate a thermostatic expansion valve?

  • 3
  • 2
  • 1
  • 4

4: A moisture indicator must

  • be filled with liquid
  • be yellow
  • change color when exposed to moisture
  • be sight side up

5: How are refrigerant blends classified?

  • Blends don't have to be classified
  • Based on best case Fractionation
  • Based on worst case fractionation
  • Based on the oil used

6: Where can 50/50 solder be used on?

  • suction line
  • liquid line
  • discharge line
  • none of the above

7: If the spring is adjusted to increase the superheat, this new setting will

  • allow more liquid into the evaporator
  • shorten the frost line
  • have no effect on the frost line
  • lengthen the frost line

8: Fusible plugs shall not be used with pressure vessels of

  • 3 cubic feet or more
  • 15 cubic feet or more
  • 15 square feet or less
  • 3 cubic feet or less

9: A Lithium-bromide system is an absorption system that

  • uses salts as an absorbent and lithium bromide as a refrigerant
  • uses ammonia as a refrigerant and lithium bromide as an absorbent
  • uses water as a refrigerant and lithium bromide as an absorbent
  • uses water as a absorbent and lithium bromide as a refrigerant

10: How many volts would you read on a 480V system phase to phase?

  • 480
  • 277
  • 1/3 the voltage

11: How are safety controls wired in a circuit?

  • Parallel
  • Series
  • Either series or parallel
  • Series/parallel

12: What happens to copper joints when overheated?

  • nothing
  • joint becomes oxidized and ditorted
  • copper becomes harder
  • none of the above

13: "R" represents ___ in the Ohm's law formula

  • capacitance
  • voltage
  • resistance
  • amperage

14: R-11 has the greatest corrosive effect on

  • Bronze
  • Aluminum
  • Copper
  • Magnesium

15: A pressure vessel having an inside diameter of 6” or less shall be sufficient to withstand ____times the pressure of the saturation temperature of the refrigerant or ____times the critical pressure of the refrigerant, whichever is less.

  • 6.6, 6.6
  • 2.5, 3.0
  • 3.0, 3.5
  • 2.5, 2.5

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

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

17: When an inspection is needed, how often must it be done?

  • every 24 months
  • every 18 months
  • every 36 months
  • annually

18: What instrument is used to measure very high resistance?

  • meg ohmmeter
  • ammeter
  • voltmeter
  • tape measure

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

  • 10
  • 50
  • 1
  • 100

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

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

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

  • Centrifugal
  • Scroll
  • Screw
  • Reciprocating

22: If the power element on an expansion valve should lose its charge, the valve would

  • Stay open
  • Under feed
  • Close
  • Over feed

23: Which of the following are considered inorganic refrigerants?

  • R-717 and R-718
  • 410A and R-407C
  • R-500 and R-502
  • None of the above

24: R-410A is classified as a ____ refrigerant on the safety matrix.

  • A-2
  • A-1
  • B-2
  • B-1

25: The level of voltage caused by back electromagnetic force that opens the contacts of a potential relay in order to take the start capacitor out of the circuit is

  • boost voltage
  • pick up voltage
  • run voltage
  • lift voltage