Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: What happens to copper joints when overheated?

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

2: What is the temperature that a liquid and a vapor can exist in equilibrium called?

  • Dry bulb temperature
  • Saturated temperature
  • Wet bulb temperature
  • Critical temperature

3: An example of an "Expendable Refrigerant" is

  • liquid oxygen
  • ammonia
  • lithium bromide
  • liquid nitrogen

4: Clearance volume

  • is the same on all compressors
  • varies depending on compressor speed
  • affects compressor capacity
  • has no effect on compressor capacity

5: What was the main reason for enacting the no venting rule of July 1, 1992?

  • Ozone depletion
  • Green house effect
  • Global warming potential
  • All of the above

6: Walls and doors of a machinery room shall be at least _____ hour(s) fire rated.

  • 1
  • 2
  • 5
  • 3

7: A halide torch is most useful with a freon compression system

  • to release a sticking valve
  • to detect refrigeration leaks in piping joints
  • to remove from from TXV's and evaporator coils
  • to sweat flanges on the refrigeration piping

8: Class 3 refrigerants are

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

9: What is the purpose of suction/discharge traps?

  • to ensure proper oil return to the compressor
  • to keep oil inside the evaporator for proper oil return to the compressor
  • to keep oil inside of the accumulator for proper return to the compressor
  • all of the above

10: Which winding have the most turns?

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

11: Trichlorofluoromethane is the name of what refrigerant?

  • R-11
  • R-113
  • R-502
  • R-12

12: Pressure limiting devices are not required for systems containing less then ________ refrigerants.

  • 6.6 lbs
  • 22 lbs
  • 44 lbs
  • 13.9 lbs

13: Excessive head pressure is often caused by

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

14: What is the voltage of each leg to ground of a three-phase motor with a 460v supply voltage?

  • 240v
  • 277v
  • 208v
  • 120v

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

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

16: A motor starter is a device that includes an overload and a _______?

  • contactor
  • 2-pole contacts
  • duel-coil
  • all of the above

17: _____ and its alloys are suitable for use with ammonia systems.

  • Copper
  • Zinc
  • Magnesium
  • Aluminum

18: A motor starter contains a thermal overload and a

  • transformer
  • contactor
  • solenoid
  • 3-way relay

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

  • series-parallel
  • series
  • junction
  • parallel

20: 746 watts is equal to

  • 1 hp
  • 10 hp
  • Pi
  • 100 hp

21: The principle used in continuous type absorption systems is

  • Charles's Law
  • Boyle's Law
  • Ohm's Law
  • Dalton's Law

22: A 3-cubic foot receiver must have what type of relief valve?

  • fusible plug
  • relief valve
  • rupture device
  • none of the above

23: Name a CFC refrigerant(s):

  • R-11
  • R-12
  • R-123
  • both a & b

24: Where are the three places that the discharge from an ammonia relief valve be piped?

  • atmosphere, tank containing water, where the A.H.J. indicates
  • underground, into drain, into mechanical room
  • to chemical neutralizing tank only
  • none of the above

25: What is specific heat?

  • measured heat
  • heat required to raise the temperature of 1lb of a substance 1 degree
  • the specific heat required to change the state of one cubic foot of air to steam
  • none of the above