Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: A low oil switch is typically

  • non used on semi-hermetic compressors over 10 ton capacity
  • manual reset
  • time-delay auto reset
  • automatic reset

2: If a halide torch is used for leak detection, what color is the flame if it detects a leak?

  • red
  • orange
  • green
  • blue

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

  • copper
  • black iron
  • magnesium
  • stainless steel

4: The maximum permissible amperage draw for a 40VA transfomer with a secondary voltage of 24V is

  • .8
  • .1
  • 1.2
  • 1.7

5: Who approves containers for refrigerants?

  • E.P.A
  • D.O.D
  • D.O.T
  • D.O.E

6: Who is permitted to access a refrigeration machine room?

  • Any employee
  • Contractors only
  • Authorized persons only
  • Anyone, it's a completely safe area

7: What effect does the temperature of air have on humidity?

  • warmer air holds more moisture then cooler air
  • cooler air holds more moisture then warmer air
  • air has no effect of humidity
  • none of the above

8: On a pumpdown system, the liquid-line solenoid is controlled by the

  • defrost timer
  • thermostat
  • low-ambient controller
  • low pressure switch

9: Atmospheric pressure is equal to

  • 29.92" Hg
  • 14.7 psia
  • 14.7 psig
  • both a & b

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

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

11: When a receiver is greater than 3 cubic feet but less than 10 cubic feed, what is the minimum relief device required?

  • fusible plug
  • relief valve
  • rupture disc
  • all of the above

12: Refrigerants shall be classified by

  • maximum permissible quantities of each group
  • color codes
  • toxicity and flammability
  • requirements for commercial, industrial, and residential occupancies

13: 746 watts is equal to

  • 10 hp
  • 1 hp
  • Pi
  • 100 hp

14: After setting up a forward curved fan for the desired conditions, something happened to lower the total static pressure the fan had to operate against. Which would occur?

  • CFM and HP increase
  • CFM and HP decrease
  • RPM and CFM increase
  • CFM and RPM decrease

15: What should never be used in pressure testing refrigeration systems?

  • Oxygen
  • Compressed air
  • Nitrogen
  • Both a and b

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

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

17: Thermodynamics is the branch of science that deals with

  • state of energy
  • heat energy
  • molecular therory
  • energy due to motion

18: Suction line oil traps should be installed when the condenser is

  • in the basement and the evaporator is on the third floor
  • on the third floor roof and the evaporator is in the basement
  • more than 100' away from the evaporator
  • located outside the operates in temperatures below 35F

19: The outer portion of shell of the compressor used on low-pressure chillers is called the

  • baffle
  • suction
  • volute
  • nozzle

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

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

21: Which occupancy can ammonia be used in?

  • industrial
  • commercial
  • redifential
  • depends on the quantity of freon

22: Pairs of mating stop valves that allow sections of a system to be joined before opening these valves or separated after closing them are

  • companion or block valves
  • gate or globe valves
  • ball valves
  • king valves

23: Ammonia systems use ____ pressure to adjust oil pressure

  • discharge
  • liquid
  • air
  • stream

24: While the system is operating, the discharge line should be

  • too hot to hold by hand
  • room temperature
  • 10-15F warmer than ambient
  • at the same temperature as the crankcase

25: R-12 is

  • dichlorodifluoromethane
  • trichlorofluoromethane
  • dichloromethane
  • dichlorofluoromethane