Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: A machine room with a refrigerant system using ammonia shall

  • be provided with a continuously operated ventilation system
  • be considered a non-hazardous location in accordance with National Electrical code
  • have no flame producing apparatus permanently installed and operated
  • All of the above

2: Lithium-bromide, Li-Br, is best characterized as a

  • sand
  • salt
  • soil
  • sugar

3: When a refrigeration or air conditioning system is installed

  • the form of certificate shall be authorized by the Department of Pubic safety
  • it shall not be operated below prescribed pressures
  • it shall be approved by the owner for proper operation.
  • a field inspection shall be made before it is put into service

4: The leaving chilled water set point for comfort cooling is typically?

  • 38
  • 60
  • 66
  • 45

5: If the suction pressure is low and the evaporator temperature high, the cause will be a?

  • overcharged
  • compressor suction valve stuck open
  • too small evaporator
  • starved evaporator

6: A tachometer is an instrument used to measure

  • speed
  • static pressure
  • air velocity
  • RPM

7: Name a CFC refrigerant(s):

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

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

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

9: Foaming of oil in a compressor is most likely to occur

  • when ambient temperature are low
  • at start-up
  • when there is insufficient air across the condenser(i.e., dirty coil)
  • when the evaporator temperatures are below 32F

10: Pipe identification labels are required when the system contains more than

  • 65 lbs
  • 120 lbs
  • 55 lbs
  • 110 lbs

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

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

12: What type of material can't be used on the outlet of a relief valve?

  • Stainless steel
  • PVC
  • Magnesium alloy
  • Copper

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

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

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

  • 1
  • 15
  • 5
  • 20

15: Ammonia systems use ____ pressure to adjust oil pressure

  • discharge
  • stream
  • liquid
  • air

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

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

17: How much clearance do you need around the perimeter of electrical panels?

  • 24"
  • 12"
  • 36"
  • 18"

18: A total of all group A-2,B-2, A-3, and B-3 refrigerants shall not exceed ____ lb in the occupied areas and machinery rooms of institutional occupancies.

  • 550
  • 100
  • 50
  • 350

19: Pressure vessel having an inside diameter exceeding 6” with an internal pressure greater than 15psig shall be marked directly on or on the nameplate the letters _______________ signifying compliance with the ASME Boiler & Pressure Vessel Code.

  • “UL”
  • “UV”
  • “U” or “UM”
  • “UM” and “UV”

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

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

21: What effect does the temperature of air have on humidity?

  • warmer air holds more moisture then cooler air
  • cooler air holds more moisture then warmer air
  • air has no effect of humidity
  • none of the above

22: What measures gas pressure?

  • Hygrometer
  • Manometer
  • Hydrometer
  • Barometer

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

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

24: What device measures the specific gravity of a substance?

  • Thermometer
  • Manometer
  • Hydrometer
  • Hygrometer

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

  • To chemical neutralizing tank only
  • Underground, into drain, into mechanical room
  • Atmosphere, Tank containing water, where the AHJ indicates.
  • None of the above.