Topics: All categories in the pool
1: On a 460V motor, what is he MAXIMUM voltage that can be safely applied to it?
- 506v
- 550v
- 660v
- None of the above
2: The actual expansion curve of compressor follows most nearly which one of the following
- Adiabatic
- Pressure-Temperature
- Isothermal
- Volume
3: All low-pressure chillers use which type of compressor?
- Centrifugal
- Reciprocating
- Scroll
- Rotary
4: Pressure vessels having an inside diameter of 6” or less shall be protected by
- a pressure relief device
- either a fusible plug or a pressure relief device
- Pressure vessels having an inside diameter of 6” or less need no such protection unless otherwise specified
- a fusible plug
5: The instrument used to measure the specific gravity of absorption chiller solutions is the
- hydrometer
- anemometer
- Psychrometer
- refractometer
6: A normal operating evaporator temperature of R-22 for air conditioning is typically
- 58F
- 55F
- 32F
- 45F
7: What should not (and can not) be located between a pressure imposing device and a pressure-limiting device?
- Stop valve
- Muffler
- Foot valve
- Moisture indicator
8: Low pressure chiller systems use what type of compressor?
- Screw
- Reciprocating
- Scroll
- Centrifugal
9: Which refrigerant class listed below is the most flammable?
- C3
- B2
- A3
- A2
10: 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
11: Which refrigerant class listed below is the most flammable?
- C-3
- A-1
- B-2
- A-3
12: Gauge pressure is
- Barometric pressure
- Force of pressure above that of atmosphere
- Absolute pressrue
- Atmospheric pressure
13: The test pressure applied to the high side of each factory-assembled refrigerating system shall be at least equal to the design pressure of
- the high side
- the aggregate of the high side and low side
- 2.5 times the design pressure
- the low side
14: A compressor that increases vapor pressure by changing the internal volume of the compression chamber is called?
- Low Pressure displacement
- Pressure induced displacement.
- Positive displacement
- Non-positive displacement
15: In an air conditioning plant which an indirect low side, water is used inside of bring: the proper sequence of operating the plan is
- start the fan and circulating pump
- reset the expansion valve
- reset the safety valve
- start the comrpessor
16: Insurance companies shall forward each inspection report of all refrigeration or A/C systems to the Chief of Inspections within
- 14 days
- 1 week
- 30 days
- 2 months
17: What is the temperature that a liquid and a vapor can exist in equilibrium called?
- Critical temperature
- Wet bulb temperature
- Dry bulb temperature
- Saturated temperature
18: Heat cannot of itself, pass from a
- cold to a warmer body
- warm to a colder body
- state of hot energy to a state of cold energy
- None of the above
19: An example of an "Expendable Refrigerant" is
- liquid nitrogen
- ammonia
- lithium bromide
- liquid oxygen
20: The principle used in continuous type absorption systems is
- Dalton's Law
- Boyle's Law
- Ohm's Law
- Charles's Law
21: An example of direct system is
- rooftop unit
- chiller
- absorber
- none of the above
22: RPM's of a centrifugal compressor are at approximately?
- 10,000
- 15,000
- 30,000
- 500
23: Refrigeration piping before being buried shall be
- leak tested
- encased in pipe duct
- pressure tested
- All of the above
24: The oil separator is always inserted in the system
- to prevent oil logging
- where it can be easily serviced
- in the discharge line
- in a cool spot
25: Heat transferred by conduction from one body to another is done
- via radiation
- via liquids
- via solids
- via heat rays