Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: A compressor in which the increase in vapor pressure is attained without changing the internal volume of the compression chamber is called

  • negative displacement compressor
  • non-positive displacement compressor
  • neutral chamber-type compressor
  • non-volumetric displacement compressor

2: Class T machine room

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

3: The 522 CMR 9.00 has adopted for reference ASHRAE ____

  • 25
  • III
  • 10
  • 15

4: What should not (and can not) be located between a pressure imposing device and a pressure-limiting device?

  • Stop valve
  • Moisture indicator
  • Muffler
  • Foot valve

5: "P" represents ______ in the Watt's law formula

  • watts
  • reactance
  • amperage
  • voltage

6: Secondary refrigerants are usually

  • Prestone anti-freeze
  • alcohol
  • expensive
  • water or brine

7: Liquid level gauges must be provided with what?

  • A relief valve
  • A red line
  • Automatic shut-offs
  • A low level mark

8: 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 cheap
  • Because it's water

9: 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

10: How is bring measured?

  • hydrometer
  • manometer
  • hygrometer
  • anemometer

11: It takes how many BTU's of latent heat/hr to boil 1 lbs of water into steam?

  • 12,000 BTU
  • 970 BTU
  • 24,000 BTU
  • 144 BTU

12: A mercury bulb controller is not recommended for

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

13: A motor starter contains a thermal overload and a

  • solenoid
  • 3-way relay
  • transformer
  • contactor

14: E = I X R is

  • Ohms Law
  • Amps Law
  • Impedance Law
  • Watts Law

15: Horizontal piping should be run level.

  • True
  • Yes, if the condenser is located above the evaporator
  • No, unless the supervisor on the job says so.
  • False

16: Can a R22 line set be reused for a 410A system and if it can be reused, what must be done to it?

  • Flush with R-718
  • Flush with R-11
  • Flush with RX-11
  • Flush with ammonia

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

  • Place sign, check for leaks, and insulate suction line
  • Make sure its compatible, notify owner, and notify AHJ.
  • Nothing must be done
  • you can never change refrigerants

18: R-12 is

  • dichlorofluoromethane
  • dichlorodifluoromethane
  • dichloromethane
  • trichlorofluoromethane

19: A “U” or “UM” marking a on a nameplate of a pressure vessels signifies compliance with Section VIII of

  • the ASME Boiler and Pressure Vessel Code
  • Section 11.3.1.5 ASHRAE 15 Standard
  • the ANSI Standard 10.7.2
  • both the ANSI Standard 10.7.2 and ASHRAE 15 Standard 11.3.1.5

20: The formula for Pure Power in a resistance circuit is

  • Watts = volts X amps
  • Kw = volts X amps
  • Watts X power factor
  • Watts X amps.

21: On a centrifugal compressor, stationary diffuser vanes are needed to

  • increase the clearance space
  • convert velocity energy to pressure
  • prevent high pressure on the packing
  • stop gas flow

22: What would be the classification for Stop & Shop grocery store?

  • Industrial
  • Large mercantile
  • Place of assembly
  • Instituional

23: What is a Category "D" fluid?

  • A fluid which is nonflammable, nontoxic, not damaging to human tissues, does not exceed 150 psig, and design temperature is between -20F to 366F
  • A typical refrigerant used on newer air conditioning and heat pump ssytems
  • Any fluid that exceeds 150 psig and has design temperature of over 366F
  • A toxic fluid, which can produce serious irreversible harm to persons on breathing or bodily contact

24: Doors communicating with outside from a mechanical room must be?

  • Self-closing, aligned, fire door
  • Self-closing, approved, fire door
  • Steel, approved, weather-stripped
  • Self-closing, wooden, fire door

25: In an electrical circuit, what is potential measured in?

  • Ohms
  • Volts
  • Amps
  • Herys