Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: Lithium-bromide, Li-Br, is best characterized as a

  • sugar
  • soil
  • sand
  • salt

2: The best way to detect ammonia in brine is

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

3: The purpose of a receiver is

  • a vessel to store refrigerant outside the system
  • to increase the capacity that the system can hold
  • to use a a later date
  • all of the above

4: A class A3 refrigerant is considered

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

5: 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.

  • 50
  • 75
  • 24
  • 100

6: Which refrigerant class listed below is the most flammable?

  • B2
  • A3
  • A2
  • C3

7: 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

8: How many opening forces operate a thermostatic expansion valve?

  • 1
  • 2
  • 3
  • 4

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

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

10: Start to Run windings will have what resistance?

  • The most resistance value
  • All will be at equal values
  • The least resistance value
  • Somewhere between the actual start winding and run winding resistance value

11: What is not a requirement of a class T machine room?

  • self-closing doors
  • fire hose connection to the building fire protection system
  • automatic ventilation
  • tight fitting doors

12: When a refrigeration or air conditioning system is installed

  • it shall not be operated below prescribed pressures
  • the form of certificate shall be authorized by the Department of Pubic safety
  • it shall be approved by the owner for proper operation.
  • a field inspection shall be made before it is put into service

13: What are the three components of a transformer?

  • Primary coil, secondary coil, and core
  • Contacts, secondary coil, and core
  • Primary core, secondary coil, and high and low voltage connectors.
  • Primary coil, secondary coil, and copper contacts

14: Refrigerant systems containing Group I refrigerants can be installed in or on public stairways.

  • True
  • False

15: Total heat of a substance is considered

  • sensible heat
  • enthalpy
  • specific heat
  • empathetical

16: A line voltage thermostat controls a 1,200 watt strip header at 120 volts. What must be minimum ampere rated of the stat be?

  • 10 amps
  • 15 amps
  • 20 amps
  • 5 amps

17: Methyl Chloride is a halogenated refrigerant and should not come in contact with

  • aluminum
  • zinc
  • magnesium
  • all of the above

18: 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

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

19: Pressure is equivalent of

  • Force / Area
  • Force X Area
  • Force
  • Area X Force

20: What percentage of amperage difference is allowable phase to phase on a HVAC circuit phased to phase?

  • 4%
  • 25%
  • 1%
  • 2%

21: The freezing point of water at sea level is?

  • 32C
  • 0F
  • -10C
  • 32F

22: An evaporator coil located near heating coil shall have a pressure-relief device installed within ______ inches of the evaporator.

  • 24
  • 36
  • 48
  • 18

23: 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

24: How far from the ground does a relief valve need to be?

  • At least 15' above grade
  • At least 20' above grade
  • At least 25' above grade
  • Not more than 3' above grade

25: 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

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