Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: The purpose of an accumulator is to

  • filter out impurities from the system
  • store excess refrigerant from the reciver
  • assure no liquid returns to the compressor
  • reduce friction loss to the flow of refrigerant

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

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

3: An example of direct system is

  • rooftop unit
  • chiller
  • absorber
  • none of the above

4: A split-phase motor has a ______ winding and a ____ winding

  • start, common
  • run, common
  • duel-run, duel-start
  • run, start

5: Halogen refrigerants are corrosive to which type of metal?

  • copper
  • stainless steel
  • black iron
  • magnesium

6: 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.

7: What's the purpose of a megohmmeter?

  • To measure low to very low resistance values
  • To alternate the current in a DC circuit in order to calculate the total impedance of a circuit
  • To measure very high resistances
  • None of the above

8: With a 5/8" X 5/8" x 3/4" tee, what size is the center connection?

  • 3/8"
  • 3/4"
  • 1/2"
  • 5/8"

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

  • Muffler
  • Stop valve
  • Foot valve
  • Moisture indicator

10: In a refrigeration system, you open a valve from the condenser and collect some material on a clean white sheet of bond paper, which of the following would you most likely be testing for?

  • checking the level of refrigerant in the system
  • testing for oil in the system
  • testing for moisture in the system
  • none of the above

11: Sensible heat is the heat added to a substance to

  • freeze it
  • raise its temperature
  • change its state
  • cause evaporation

12: 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

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

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

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

  • Stainless Steel
  • Copper
  • Aluminum
  • PVC

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

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

16: Starting relays for a single phase compressors are used to remove the starting circuit from operation when the motor reaches approximately ____ percent of its speed.

  • 75
  • 100
  • 24
  • 50

17: How many volts would you read on a 480V system phase to phase?

  • 1/3 the voltage
  • 480
  • 277

18: What type of copper is not permitted on refrigeration systems?

  • Type K
  • Type N
  • Type L
  • Type M

19: Large Mercantile occupancy is a premise or that portion of a premise where more than ____ persons congregate on levels above or below the street level to purchase personal merchandise.

  • 250
  • 350
  • 400
  • 100

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

  • 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
  • the form or certificate shall be authorized by the Department of Public Safety

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

22: The best way to detect ammonia in brine is

  • potassium of line
  • carbonation of soda
  • CO2 gas
  • nessler regaent

23: Capacity control on a centrifugal compressor is accomplished by the

  • slide vanes
  • check valves
  • pre-rotational guide vanes
  • post-rotational guide vanes

24: Institutional occupancy is

  • a premise or that portion of a premise where large numbers of people congregate and from which occupants cannot quickly vacate the space.
  • a premise or that portion of a premise from which, because they are disabled, debilitated, or confined, occupants cannot readily leave without the assistance of others.
  • a premise or that portion of a premise where people transact business, receive personal service, or purchase food and other goods.
  • None of the above

25: What type refrigerant is NOT ozone depleting?

  • HFC
  • CFC
  • Halon
  • HCFC