Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: A micron is

  • one thousandths of a millimeter
  • one millonths of a centimeter
  • a larger unit of measurement than Hg
  • one millonths of a micrometer

2: What is the amp draw of a 40 VA transformer at 24 volts

  • 1K amps
  • 1.6 amps
  • 1,000 amps
  • 106 amps

3: What is not a requirement of a Class T machine room?

  • Fire hose connected to the building fire protection system.
  • Tight fitting doors
  • Self-closing doors
  • Automatic ventilation

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

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

5: If a low-pressure chiller has a low-side leak, which of the following will most likely result?

  • High suction pressure and high discharge pressure.
  • Low suction pressure and low discharge pressure
  • Low head pressure and high suction pressure
  • High head pressure and low suction pressure

6: Heat that changes the physical state of a substance without effecting a change in its temperature is known as

  • lost heat
  • sensible heat
  • specific heat
  • latent heat

7: What is a Category "M" fluid?

  • Any fluid that exceeds 150 psig and has design temperatures over 366F
  • A fluid which is nonflammable, nontoxic, not damaging to human tissues, does not exceed 150 psig, and the designed temperature is between -20F to 366F
  • A toxic fluid, which can produce serious irreversible harm to persons on breathing or bodily content
  • A typical refrigerant used on newer air conditioning and heat pump systems

8: What type of relief valve is used on a CO2 system?

  • gate valve
  • glove disc
  • rupture disc
  • fusible plug

9: R-22 is classified as a ____ refrigerant on the safety matrix.

  • A-2
  • B-2
  • A-1
  • B-1

10: Ammonia can come in contact with _______ ?

  • Aluminum
  • Copper tubing
  • Brass
  • Copper

11: How many different groups of refrigerants are there?

  • 7
  • 3
  • 15
  • 11

12: High side floats are used on centrifugal chiller systems are are considered critically charged systems.

  • False
  • True
  • are obsolete.
  • depends on the type of refrigerant being used

13: If your suction line is warmer than the room temperature, this may indicate

  • below normal superheat
  • plugged air filter
  • an over charge
  • a low charge

14: A normally operating R-410A system with a condensing temperature of 110F will have a high side pressure of around ______ psig

  • 255 psig
  • 365 psig
  • 125 psig
  • 327 psig

15: An azeotropic refrigerant is

  • a mixture of two or more refrigerants that boil at about the same temperature minimizing temperature glide.
  • a mixture of two or more refrigerants that boil at much different temperatures causing temperature glide
  • a mixture of two or more refrigerants that boil at much different temperatures minimizing temperature glide
  • none of the above

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

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

17: In an air conditioning plant which an indirect low side, water is used inside of bring: the proper sequence of operating the plan is

  • start the comrpessor
  • reset the safety valve
  • start the fan and circulating pump
  • reset the expansion valve

18: How would you know if there was a loss of crankcase pressure?

  • oil will foam
  • oil level will rise
  • oil will thin out
  • oil will thicken

19: Pressure vessels of 10 cubic feet or more gross volume shall use

  • at least one rupture member
  • a dual pressure-relief valve if charging into the atmosphere
  • at least three means of discharge and/or rupture discs
  • both a and b are correct

20: A start capacitor is wired in _____ with the start windings.

  • series-parallel
  • parallel
  • junction
  • series

21: The difference between saturated liquid and saturated vapor is

  • heat
  • pressure
  • volume
  • temperature

22: Halogenated refrigerants cannot be used with what material?

  • Aluminum
  • Magnesium alloy
  • Stainless steel
  • Copper

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

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

24: A direct system

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

25: In a system designed for sub-zero ambient temperatures, what must be added?

  • Low-ambient kit
  • Infrared dye for leak identification
  • Booster compressor
  • Nitrogen