Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: If a halide torch is used for leak detection, what color is the flame if it detects a leak?

  • blue
  • orange
  • green
  • red

2: In a low temperature refrigeration system, the benefit of the system using P.A.G. oil is

  • it is hydroscopic
  • it traps moisture
  • viscosity
  • all of the above

3: Which winding have the most turns?

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

4: Gauge pressure is

  • atmospheric pressure
  • force of pressure above that of atmospheric
  • absolute pressure
  • what a gauge reads when checking pressures on a chilled water system.

5: 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

6: 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

7: The main purpose of a refrigerant detector in a machinery room is to

  • inform there is a refrigerant leak int he system
  • detect toxins in the air caused by a refrigerant leak
  • to set off an alarm when there is refrigerant present inside the room
  • all of the above

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

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

9: Brazed joints melt at temperatures above

  • 1,000F
  • 500F
  • 800F
  • 1,200F

10: When should a relief valve start to function?

  • Before the purge station discharges
  • Two times it's working pressure
  • At it's set pressure
  • 10 psi before it's set pressure

11: What is Absolute Zero?

  • -640F
  • -460F
  • -773F
  • -400F

12: 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

13: How does a centrifugal compressor create the pressure differential needed to move refrigerant through the system?

  • Nesting scrolls
  • Fan-like action
  • Suction and discharge valves
  • Rotating vanes

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

  • 24"
  • 12"
  • 36"
  • 18"

15: A secondary coolant is defined as

  • a low temperature refrigerant used for cascading systems
  • any liquid used for the transmission of heat without a change of state in A/C refrigeration systems having flash point above 150F
  • any refrigerant direcly in contact with the cooling space for process cooling
  • a combination of interconnected parts from a closed circuit in where fluid is circulated for the purpose of cooling for a refrigeration system.

16: What do you need to do when you install a new system?

  • Document the superheat and subcooling reading
  • Have it inspected
  • Add refrigerant
  • Insulate the suction line before you take a superheat reading

17: How many BTU's is produced by one watt of energy

  • 1
  • 3.00
  • 2.57
  • 3.41

18: Heat is a form of

  • energy
  • work
  • matter
  • power

19: A Category D fluid

  • is when the fluid handled is non flammable, nontoxic, and not damaging to human as defined in ANSI/ASME Process Piping.
  • is when the design pressure does not exceed 150 psi
  • a fluid for service piping in which the potential for personnel exposure is judged to cause harm and irreversible damage to those persons exposed to it
  • Both a and b are correct

20: Usually dry bulb temperature is

  • not important and shall be ignored
  • higher than wet bulb temperature
  • same as wet bulb temperature
  • lower than dry bulb temperature

21: What type of voltage cause a potential relay to open?

  • 24 volt supply from the thermostat
  • 120 volt line voltage
  • Pick-up voltage
  • none of the above

22: What measures gas pressure?

  • Hygrometer
  • Manometer
  • Hydrometer
  • Barometer

23: Which has more turns in the windings: Start windings or Run windings?

  • Start windings
  • Run windings
  • They both have the exact same turns
  • Depends on the system and capacitor used

24: Which of the following is an inorganic refrigerant?

  • R-22
  • Ammonia
  • Chlorofluorocarbons
  • All of the above

25: If a refrigerant leaving the condenser is 94F and the condensing temperature is 105F, the subcooling is

  • 11F
  • 29F
  • 21F
  • 9F