Topics: All categories in the pool
1: Thermodynamics is the branch of science that deals with
- heat energy
- state of energy
- molecular therory
- energy due to motion
2: A premise or that portion of a premise where large numbers of people congregate and from which occupants cannot quickly vacate the space such as auditoriums, ballrooms, classrooms, passenger depots, restaurants, and theaters is considered a(n)
- illegal occupancy
- institutional occupancy
- public assembly occupancy
- commercial occupancy
3: What is not a requirement of a class T machine room?
- automatic ventilation
- fire hose connection to the building fire protection system
- tight fitting doors
- self-closing doors
4: Pressure relief devices are marked with a ____________ signifying compliance with the ASME Boiler & Pressure Vessel Code.
- UV or UR
- UL and UM
- UL and UR
- UM or UL
5: 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
6: Atmospheric pressure is equal to
- 29.92" Hg
- 14.7 psia
- 14.7 psig
- both a & b
7: On a ammonia compressor, the pressure of a forced fed oil pump is changed by varying the
- opening at the pump outlet
- cooling temperature set-point
- adjustment of the spring tension of the TXV
- opening at the pump inlet
8: Which of the following is a drop-in for R-22
- R-410A
- R-134A
- R407C
- None of the above
9: What is the voltage of each leg of a 480 Volt three-phase motor?
- 208v
- 120v
- 277v
- 240v
10: Heat that changes the physical state of a substance without effecting a change in its temperature is known as
- specific heat
- lost heat
- latent heat
- sensible heat
11: The actual expansion curve of compressor follows most nearly which one of the following
- Pressure-Temperature
- Isothermal
- Adiabatic
- Volume
12: What is a high-side float?
- Located in the evaporator, is a float-type metering device that rises to reduce refrigerant flow when the liquid refrigerant level rises in the low side of the chiller
- Located in the liquid line entering the evaporator, is a float-type metering device that rises to reduce refrigerant flow when the liquid refrigerant level rises in the high side of the chiller
- Located in the liquid line entering the evaporator, so when the refrigerant level is higher in the liquid line than the evaporator, the float rises to allow more refrigerant flow into the evaporator
- An electronic-type metering device that contains a float assembly within the device which can accurately meter refrigerant into the evaporator as the load varies
13: How much clearance do you need around the perimeter of electrical panels?
- 36"
- 12"
- 24"
- 18"
14: What must be done to refrigerant pipes before being buried?
- Certified
- Leaked checked
- Encased
- Coated
15: What is absolute humidity?
- the amount of moisture in the air per one pound of 50% RH air
- the amount of moisture in the air in grains of cubic feet of volume
- the amount of moisture in the air in grains of square feet of volume
- none of the above
16: The normal operating evaporator temperature of R-410A for air conditioning is typically
- 158F
- 155F
- 45F
- 32F
17: The evaporator is a device to
- absorb heat into the refrigeration system
- remove heat from the refrigeration system
- Keep the compressor busy
- store liquid refrigerant
18: What kind of system uses two different refrigerants in separate systems dependent on each other?
- Simple
- Low pressure
- R-414B
- Cascade
19: The pressure relief device of a positive displacement compressor shall discharge in the ______________or in accordance with 9.7.8
- high side of the system
- the vapor side of the system
- low side of the system
- the liquid side of the system
20: 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
21: When air is ducted through a machine room that services occupied space, What must be done?
- Flanged and gasketed
- Ducted and sealed
- Welded and seamed.
- Insulated and cross broke
22: 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 RPM decrease
- CFM and HP increase
- CFM and HP decrease
- RPM and CFM increase
23: Joints in refrigeration piping must be _____ before being covered?
- Leak tested
- Insulated
- Pressurized
- Inspected
24: The generator shell contains the
- condenser and the absorber
- condenser and the generator
- evaporator and the absorber
- condenser, the evaporator, and the generator
25: Sublimation occurs when
- liquid is formed from a gas
- gas is formed directly from a solid
- gas is formed from a liquid
- ice melts and turns to water