Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: What are the three components of a transformer?

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

2: Which is the lowest vacuum?

  • 1,000 Microns
  • 5 psig
  • 5" hg
  • 10 psia

3: R-410A can segregate in the system or chemically change its composition due to a leak.

  • True
  • False

4: How many closing forces operate a thermostatic expansion valve?

  • 1
  • 4
  • 2
  • 3

5: Single compound Refrigerants are classified by what two criteria?

  • Flammability and temperature range
  • Weight and color
  • Temperature range and hazardousness
  • Flammability and toxicity

6: The proper location for an oil separator is between the

  • condenser and receiver
  • compressor and condenser
  • evaporator and compressor
  • receiver and metering device

7: A motor starter contains a thermal overload and a

  • contactor
  • solenoid
  • transformer
  • 3-way relay

8: A pressure-limiting device isn't required on a factory-sealed system containing less than ____ lbs.

  • 22
  • 25
  • 50
  • 66

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

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

10: The instrument used to measure the specific gravity of absorption chiller solutions is the

  • anemometer
  • hydrometer
  • refractometer
  • Psychrometer

11: 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.

  • 24
  • 100
  • 75
  • 50

12: Dual-pressure relief devices should be installed on

  • vessels of 10 cubic feet or more
  • vessels of 3 cubic feet or less
  • vessels of 10 cubic feet or less
  • vessels of 3 cubic feet or more

13: 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

14: Which of the following types of oils are hygroscopic?

  • polyolester (POE)
  • polyalkylene glycol (PAG)
  • naphthene mineral
  • both a and b

15: Group A3 refrigerants have a ______ flammability rating than Group B1 refrigerants

  • lower
  • the same
  • there is no Group B1 refrigerants
  • higher

16: The critical temperature of a refrigerant gas occurs when

  • any increase in pressure will not liquefy the gas
  • the gas returns to a liquid
  • the gas is no longer saturated
  • any decrease in pressure will cause condensation

17: A chiller entering and leaving temperature difference is?

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

18: A positive displacement compressor is

  • is a reciprocating type compressor with 2 or more pistons
  • where the compressor's suction pressure and the compressor;s discharge pressure is more than 50 PSI
  • a compressor in which the increase in pressure is attained by changing the internal pressure of the compression chamber
  • a compressor in which the increase in pressure is attained by changing the internal volume of the compression chamber

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

  • 4%
  • 1%
  • 2%
  • 25%

20: All low-pressure chillers use which type of compressor?

  • Scroll
  • Centrifugal
  • Rotary
  • Reciprocating

21: High pressure controls should be set no higher than

  • 10% of set point
  • 80% of set point
  • 25% of set point
  • 90% of set point

22: When this is installed on the high side of a system, it must be capable of reading 1.2 times the design pressure (ASHRAE 15 9.11.3)

  • Pressure gauge
  • Temperature gauge
  • Sight glass gauge
  • All of the above

23: Name an HCFC refrigerant(s):

  • R-22
  • R-123
  • R-11
  • both a & b

24: What refrigerant is an inorganic compound?

  • R-410A
  • R-22
  • R-132A
  • Ammonia

25: What is not a requirement of a Class T machine room?

  • Self-closing doors
  • Tight fitting doors
  • Automatic ventilation
  • Fire hose connected to the building fire protection system.