Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: Ammonia vaporization takes place at what temperature?

  • -460F
  • -32F
  • -28F
  • -110F

2: On a centrifugal compressor, stationary diffuser vanes are needed to

  • stop gas flow
  • increase the clearance space
  • prevent high pressure on the packing
  • convert velocity energy to pressure

3: On a TXV, the purpose of an external equalizer is to?

  • balance the evaporator load
  • allow a greater adjustment spam
  • Increase the pressure on the top of the power head diaphragm
  • compensate for a pressure drop across the evaporator coil

4: A High-Probability System

  • is a system highly likely to leak form a failed connection or component of such system
  • is such that a leak of refrigerant from a failed connection will enter an unoccupied space
  • is such that a leak of refrigerant from a failed connection will enter the occupied space
  • is such that any leak will cause injury or death to anyone within a 100 square foot area

5: How are a compressor and condenser fan wired?

  • series
  • parallel
  • parallel-series
  • series-parallel

6: Can you use Ammonia in industrial applications?

  • Yes, Under certain condidtions
  • When mixed with R-718
  • Yes, always
  • No, never

7: A chilled water pump's suction gauge reads 10 psig. The discharge gauge reads 48 psig. What is the head in feet the pump is working against?

  • 96
  • 58
  • 88
  • 38

8: Can a R22 line set be reused for a 410A system and if it can be reused, what must be done to it?

  • Flush with R-11
  • Flush with RX-11
  • Flush with R-718
  • Flush with ammonia

9: Refrigerant systems containing Group I refrigerants can be installed in or on public stairways.

  • True
  • False

10: What percentage of amperage difference is allowable phase to phase on a HVAC circuit phased to phase?

  • 2%
  • 1%
  • 25%
  • 4%

11: Booster compressors connect to the ____ side of the compressor

  • oil side
  • vapor
  • liquid
  • low side

12: The most common type of motor starter is

  • part winding starter
  • duel-winding starter
  • across the line starter
  • delts-wye starter

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

  • 20
  • 15
  • 5
  • 1

14: Sensible heat is the heat added to a substance to

  • change its state
  • cause evaporation
  • raise its temperature
  • freeze it

15: The difference between saturated liquid and saturated vapor is

  • heat
  • pressure
  • temperature
  • volume

16: Ammonia shall be discharged into ____________ or a tank containing one gallon of water for every pound of ammonia.

  • the atmosphere
  • a de-pressurized recovery tank with a silver top and yellow bottom
  • a tank containing two pounds of a water/lithium bromide mix for every pound of ammonia
  • All of the above

17: R-718 is rated unlimited for refrigeration quantity contained in a system. Why?

  • Because it's a non-flammable refrigerant
  • Because it's water
  • Because it's cheap
  • R-718 is not rated unlimited because it's a dangerous refrigerant

18: What device removes the start winding from the circuit of a split-phase motor once the motor reaches 75% of its rated load amps (RLA)?

  • centrifugal switch
  • printed circuit board (PCB)
  • duel-voltage switch
  • motor starter

19: The pressure relief device of a positive displacement compressor shall discharge in the ______________or in accordance with 9.7.8

  • high side of the system
  • the liquid side of the system
  • the vapor side of the system
  • low side of the system

20: Liquid level gauges shall have _____________ with one exception being that of the liquid level gauge bull’s eye type.

  • color-coded glass to determine type of refrigerant
  • moisture indicators
  • automatic closing shut-off valves
  • All of the above

21: What is NOT a positive displacement compressor.

  • Rotary
  • Scroll
  • Centrifugal
  • Reciprocating

22: 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.

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

23: 746 watts is equal to

  • Pi
  • 1 hp
  • 100 hp
  • 10 hp

24: The total amount of refrigerant stored in a machinery room in all containers not provided with relief valves shall not exceed

  • 330 lbs
  • 55 lbs
  • 500 lbs
  • 660 lbs

25: On a large centrifugal system, what meters the flow to the evaporator?

  • Cap tube.
  • TXV
  • High side float
  • Low side float