Topics: All categories in the pool
1: All serviceable components of a refrigeration system shall be provided with
- service manuals
- name plates with markings referring to pressure and temperature in accordance with ASME Boiler and Pressure Vessel Code
- safe access
- manufactures instructions on start-up procedures
2: Megaohm meter's main function is
- to detect weak motor winding insulation of a refrigeration or air conditioning compressor by creating high DC voltages to the compressor
- to detect very high resistances to ground of refrigeration or air conditioning compressors
- to test very high value capacitors for large 3-phase refrigeration compressors and blower motors.
- Both a and b are correct
3: The main purpose of a refrigerant detector in a machinery room is to
- inform there is a refrigerant leak int he system
- detect toxins in the air caused by a refrigerant leak
- to set off an alarm when there is refrigerant present inside the room
- all of the above
4: Which of the following is an inorganic refrigerant?
- R-22
- Ammonia
- Chlorofluorocarbons
- All of the above
5: copper and its alloys shall not be used in contact with _____ except as a component of bronze alloys for bearing or other non-refrigerant containing uses.
- CFC-11
- Lithium bromide
- ammonia
- HCFC-123
6: If the compression ratio on a centrifugal compressor rises too high, the compressor will stop pumping and make a loud sound commonly referred to as a
- purge
- splurge
- surge
- merge
7: 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?
- RPM and CFM increase
- CFM and RPM decrease
- CFM and HP increase
- CFM and HP decrease
8: Refrigerants shall be classified by
- maximum permissible quantities of each group
- requirements for commercial, industrial, and residential occupancies
- color codes
- toxicity and flammability
9: How many gallons of water do you need per pound of ammonia?
- 10
- 1
- 50
- 100
10: Where would the EPR valve be located on a multiple evaporator system?
- outlet of high temperature evaporator
- outlet of low temperature evaporator
- inlet of the low temperature evaporator.
- outlet of the liquid line
11: What is the maximum voltage range allowed on an electrical circuit?
- 15%
- 10%
- 20%
- 5%
12: The density of a gas refers to
- pounds per cubic foot
- pounds per square foot
- pounds per absolute pressure
- cubic feet per pound
13: Suction valve unloaders afford an effective means of
- evaporator control
- superheat control
- capacity control
- refrigerant control
14: An example of direct system is
- rooftop unit
- chiller
- absorber
- none of the above
15: pressure relief valves must discharge to the atmosphere at a location not less than 15 feet from ground level and ____ feet from any window, ventilation opening, or exits of buildings.
- 20
- 10
- 15
- 25
16: The formula for Pure Power in a resistance circuit is
- Watts = volts X amps
- Watts X power factor
- Kw = volts X amps
- Watts X amps.
17: A halide torch is most useful with a freon compression system
- to release a sticking valve
- to sweat flanges on the refrigeration piping
- to remove from from TXV's and evaporator coils
- to detect refrigeration leaks in piping joints
18: Start to Run windings will have what resistance?
- The least resistance value
- The most resistance value
- Somewhere between the actual start winding and run winding resistance value
- All will be at equal values
19: Which of the following is a drop-in for R-22
- R-410A
- R-134A
- R407C
- None of the above
20: Liquid line filter-driers on a 410A system must be rated for no less than
- 1000 psig
- 600 psig
- 400 psig
- 200 psig
21: Capacity control on a centrifugal compressor is accomplished by the
- pre-rotational guide vanes
- check valves
- slide vanes
- post-rotational guide vanes
22: Which of the following is not an air velocity meter?
- Anemometer
- Hydrometer
- Anemotherm
- Velometer
23: Color is important in oil because
- can tell us something about the refining of oil
- allows you to see into crankcase
- it indicates the viscoisty.
- it makes sight glasses easy to read
24: 746 watts is equal to
- 100 hp
- 1 hp
- 10 hp
- Pi
25: If a low-pressure chiller has a low-side leak, which of the following will most likely result?
- Low head pressure and high suction pressure
- High head pressure and low suction pressure
- High suction pressure and high discharge pressure.
- Low suction pressure and low discharge pressure