Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: A direct system

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

2: A 120 volt motor rated at 1,800 watts. You find the motor is drawings 25 amps. The motor is

  • drawing RLA and is running as it should
  • drawing LRA and is seized and should be replaced.
  • running hot
  • none of the above

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

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

4: The gauge thickness required on a CO2 tank construction is

  • 1/8"
  • 5/16"
  • 1/16"
  • 3/32"

5: Systems containing more than 110 pounds must have stop valves located at the

  • compressor suction inlet
  • compressor discharge outlet
  • receiver inlet and outlet
  • All of the above

6: What should never be used in pressure testing refrigeration systems?

  • Oxygen
  • Compressed air
  • Nitrogen
  • Both a and b

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

  • Copper
  • Stainless Steel
  • PVC
  • Aluminum

8: Heat transferred by conduction from one body to another is done

  • via liquids
  • via radiation
  • via solids
  • via heat rays

9: Pressure relief valves shall be marked with the data from

  • Section IV Division of the ASME Boiler & Pressure Code
  • Section VIII Division of the ASME Boiler & Pressure Code
  • Section XIII Division of the ASME Boiler & Pressure Code
  • Section I Division VIII of ASME Boiler & Pressure Code

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

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

11: 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

12: What measures gas pressure?

  • Hygrometer
  • Manometer
  • Barometer
  • Hydrometer

13: All machine rooms must be outfitted with a detector that _______?

  • activates an audible alarm
  • activates a visual alarm
  • starts the ventilation system
  • All of the above

14: On a single phase motor, when does the start winding cut out?

  • 50% of its RLA speed
  • 75% of its RLA speed
  • 100% of its RLA speed
  • 25% of its RLA speed

15: 14.7 psia is equivalent to

  • atmospheric pressure at seal level
  • 29.92" Hg
  • 0 psig
  • All of the above.

16: Laten heat is associated with a change in state of a refrigerant but not temperature

  • True
  • False

17: The two float-type metering devices are the

  • high-side float and the low-side float
  • liquid float and the low-side float
  • liquid float and the vapor float
  • vapor float and the low-side float.

18: Low ambient controls are used when

  • on air conditioning systems only
  • when systems run all year round
  • economizers are used
  • always

19: In a horizontal shell & tube condenser, the ammonia is liquefied by

  • passing thru the tubes from top to bottom
  • removing the latent heat of fusion
  • removing the latent heat of vaporization
  • water sprayed over condenser

20: A line voltage thermostat controls a 1,200 watt strip header at 120 volts. What must be minimum ampere rated of the stat be?

  • 15 amps
  • 20 amps
  • 10 amps
  • 5 amps

21: 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

22: What is used to check very low air pressures in air conditioning duct?

  • Barometer
  • Vacuum gauge
  • Manometer
  • Anemomter

23: The ASHRAE Standard 34 requires what type of alarm for equipment rooms using HCFC-123?

  • A group sensing
  • phosgene gas sening
  • refrigerant sensing
  • CO Sensing

24: Where a refrigeration or air conditioning system is installed,

  • the form or certificate shall be authorized by the Department of Public Safety
  • A field inspection shall be made before it is put into service
  • it shall not be operated below prescribed pressuers
  • The company who installed the system must notify the fire department in the jurisdiction where installed

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

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