Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: When can 50/50 solder be used?

  • in the low side
  • in the high side
  • liquid and suction lines
  • none of the above.

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

  • 38
  • 60
  • 45
  • 66

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

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

4: Calculate the voltage in a series circuit when the total amperage is 10 amps and the resistors have values of: R1=12 ohms, R2=8 ohms, R3=4 ohms

  • 24.0 volts
  • 240 volts
  • 2.40 volts
  • 2,400 volts

5: In a system designed for sub-zero ambient temperatures, what must be added?

  • Nitrogen
  • Low-ambient kit
  • Infrared dye for leak identification
  • Booster compressor

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

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

7: B3 refrigerants are considered

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

8: The pressure relief device of a positive displacement compressor shall discharge in the ______________or in accordance with 9.7.8

  • the vapor side of the system
  • low side of the system
  • the liquid side of the system
  • high side of the system

9: A chiller entering and leaving temperature difference is?

  • 50 degrees F
  • 10 degrees F
  • 20 degrees F
  • 5 degrees F

10: Defined process piping by code CMR (528)

  • Any piping that conveys a solid, liquid or gas that is not part of the plumbing or fire protection system
  • Any piping in an industrial space
  • Any piping in an industrial or commercial space
  • All of the above

11: Which oil is hydoscopic?

  • mineral
  • polyolester
  • SW30
  • animal

12: Class 3 refrigerants are

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

13: A water regulating valve opens when

  • the head pressure rises
  • when the power is on
  • the compressor is on
  • when the power is on there is an overcharge of refrigerant

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

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

15: What type of relief valve is used on low pressure centrifugal compressor systems?

  • Spring-loaded relief valve
  • Rupture disc
  • Purge relief
  • None of the above

16: Refrigeration piping before being buried shall be

  • leak tested
  • encased in pipe duct
  • pressure tested
  • All of the above

17: When the compressor is below the condensor

  • traps are needed on the suction line
  • traps are needed on the oil return line
  • traps are needed on the discharge line
  • traps are not needed on this type of system

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

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

19: Class T machine room

  • has no flame producing apparatus permanently installed
  • shall have remote controls to stop the action of the refrigerant compressor
  • shall include closets used for setting equipment
  • shall have refrigerant leak detecting systems installed inside and outside the room

20: How are a compressor and condenser fan wired?

  • series-parallel
  • series
  • parallel-series
  • parallel

21: Each machinery room shall contain

  • a toxicity detector where the presence of ammonia or lithium bromide from a leak will concentrate
  • high and low pressure controls
  • a refrigerant detector located in an area where the refrigerant from a leak will concentrate
  • smoke and fire alarms as well as three means of egress and that egress must meet 528 CMR ventilation requirements

22: Which of the following controllers would you expect to be most sensitive to temperature changes?

  • line voltage t-stat
  • aquastat
  • immersion controller
  • low voltage t-stat

23: A room having machinery but no flame producing apparatus permanently installed and operated is considered a

  • Class A machinery room
  • Class M machinery room
  • Class B machinery room
  • Class T machinery room

24: What refrigerant were phased out in 2004?

  • R-22
  • R-11
  • R-134a
  • R-12

25: 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