Topics: All categories in the pool
1: 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
- 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
- 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
2: The actual expansion curve of compressor follows most nearly which one of the following
- Volume
- Isothermal
- Pressure-Temperature
- Adiabatic
3: The leaving chilled water set point for comfort cooling is typically?
- 66
- 45
- 60
- 38
4: Transformers are rated in
- volts
- volt-amps
- amps
- volts-ohms
5: R-123 belongs to Group
- B-2
- B-3
- B-1
- A-3
6: The absorber shell contains the
- evaporator and the absorber
- condenser, the evaporator, and the generator
- condenser and the absorber
- condenser and the generator
7: If the power element on an expansion valve should lose its charge, the valve would
- Over feed
- Stay open
- Close
- Under feed
8: It shall be the duty of the person in charge of the premises on which a refrigeration system containing more than ___ lbs of refrigerant is installed to provide a schematic drawing or panel giving directions for the operation of the system.
- 50
- 15
- 75
- 55
9: What is not a requirement of a class T machine room?
- self-closing doors
- fire hose connection to the building fire protection system
- tight fitting doors
- automatic ventilation
10: Large mercantile occupancy is
- a premise of that portion of a premise where more than 100 persons congregate on levels above of below street level to purchase personal merchandise.
- a premise of that portion of a premise where more than 50 persons congregate on levels above of below street level to purchase personal merchandise.
- a premise or that portion of a premise where more than 200 persons congregate on levels above or below street level to purchase personal merchandise
- a premise or that portion of a premise where more than 1500 persons congregate on levels above or below street level to purchase personal merchandise
11: Ammonia belongs to Group
- A-2
- A-1
- B-1
- B-2
12: NH3 is
- R-508A
- R-718
- ammonia
- lithium bromide
13: Heat is a form of
- matter
- work
- energy
- power
14: What is the state of the refrigerant leaving the evaporator?
- a high temperature superheated vapor
- a high temperature subcooled liquid
- a low temperature subcooled liquid
- low temperature superheated vapor
15: What type of voltage cause a potential relay to open?
- 24 volt supply from the thermostat
- 120 volt line voltage
- Pick-up voltage
- none of the above
16: Suction line oil traps should be installed when the condenser is
- more than 100' away from the evaporator
- in the basement and the evaporator is on the third floor
- located outside the operates in temperatures below 35F
- on the third floor roof and the evaporator is in the basement
17: When using nitrogen for brazing, the pressure should be:
- Very low
- Slightly below atmospheric
- 125 psig
- 50-100 psig
18: Pressure limiting devices are not required for systems containing less then ________ refrigerants.
- 6.6 lbs
- 44 lbs
- 13.9 lbs
- 22 lbs
19: The two float-type metering devices are the
- vapor float and the low-side float.
- high-side float and the low-side float
- liquid float and the vapor float
- liquid float and the low-side float
20: A mercury bulb controller is not recommended for
- low voltage use
- line voltage use
- use where vibration is severe
- line or low voltage use
21: R-12. R-22, and R-40 are considered Group I refrigerants.
- True
- False
22: While the system is operating, the discharge line should be
- at the same temperature as the crankcase
- too hot to hold by hand
- room temperature
- 10-15F warmer than ambient
23: Pressure vessels with an internal volume of 3 cubic feet or more
- shall use pressure relief devices
- shall use pressure relief devices or fusible plugs
- do not need pressure relief protection
- shall use fusible plugs
24: What type of copper is not permitted on refrigeration systems?
- Type N
- Type L
- Type M
- Type K
25: What is the refrigerant dichlorodifluoromethane?
- R-22
- R-12
- R-123
- R-134A