Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: A start capacitor in series with a start winding will

  • increase running efficiency
  • decrease the amp draw of the motor
  • increase the amp draw of the motor
  • increase starting torque

2: NH3 is

  • ammonia
  • R-718
  • R-508A
  • lithium bromide

3: An oil pressure safety switch should be set at

  • 10 to 15 psi below low side pressure
  • 5 to 10 psi below low side pressure
  • 10-15 psi above low side pressure
  • 5 to 10 psi above low side pressure

4: The location of the thermal bulb for the TXV on the evaporator effects

  • both the pressure and temperature in the feeler bulb
  • the amount of superheat required to operate the TXV
  • the amount of liquid in the evaporator
  • the amount of gas in the evaporator

5: A mercury bulb controller is not recommended for

  • low voltage use
  • line voltage use
  • line or low voltage use
  • use where vibration is severe

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

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

7: The solution that leaves the concentrator in an absorption chiller is referred to as the

  • absorbed solution
  • diluted solution
  • strong solution
  • weak solution

8: Where can 50/50 solder be used on?

  • suction line
  • liquid line
  • discharge line
  • none of the above

9: How much refrigerant can be stored in a mechanical room outside of the system?

  • 330
  • 150
  • 200
  • 100

10: one BTU equals

  • 3.41 hp
  • 12,000 hp
  • 31.4 hp
  • Pi

11: Heat cannot of itself, pass from a

  • cold to a warmer body
  • warm to a colder body
  • state of hot energy to a state of cold energy
  • None of the above

12: What instrument is used to measure very high resistance?

  • tape measure
  • voltmeter
  • ammeter
  • meg ohmmeter

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

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

14: 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

15: A class B1 refrigerant is considered

  • non-toxic but highly flammable
  • toxic but non-flammable
  • toxic and somewhat flammable
  • non-toxic and non-flammable

16: Setting a pressure relief device shall not exceed ___ of the design pressure

  • 75%
  • 90%
  • 80%
  • 100%

17: Before you change the type of refrigerant in a refrigeration system, what three things must be done?

  • make sure it's compatible, notify owner, notify A.H.J
  • nothing must be done
  • you can't change refrigerants
  • place sign, check for leaks, insulate

18: The dial of a pressure gauge, when installed on the high side of a system be graduated 1.2 times the designed pressure.

  • True
  • False

19: Halogenated refrigerants cannot be used with what material?

  • Aluminum
  • Copper
  • Magnesium alloy
  • Stainless steel

20: The total amount of refrigerant stored in a machinery room in all containers not provided with relief valves shall not exceed

  • 660 lbs
  • 330 lbs.
  • 55 lbs
  • 550 lbs

21: Liquid refrigerant R-22 enters an evaporator at 50.2 psig, 20F and leaves 37F, its pressure as it leaves will be

  • 43.3 psig
  • 66.1 psig
  • 50.2 psig
  • 70.8 psig

22: Whoever owns/uses a refrigeration or air conditioning system covered by this code

  • must notify the Department of Public Safety prior to starting the system
  • shall be licensed by the Commonwealth of Massachusetts according to CMR 522
  • shall make application for inspections to the Chief of Inspectors
  • None of the above

23: What must be done if refrigeration lines pass through a concrete floor?

  • insulated
  • installed through a pipe casing
  • moisture barrier
  • leak checked

24: The level of voltage caused by back electromagnetic force that opens the contacts of a potential relay in order to take the start capacitor out of the circuit is

  • run voltage
  • boost voltage
  • pick up voltage
  • lift voltage

25: 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