Topics: All categories in the pool
1: _____ and its alloys are suitable for use with ammonia systems.
- Aluminum
- Copper
- Magnesium
- Zinc
2: Dew point is
- the temperature below which water vapor in the air will start to condense
- the temperature of air of 50% RH
- the temperature below which water vapor in the air will start to evaporate
- the temperature above which water vapor in the air will start to condense
3: E = I X R is
- Impedance Law
- Ohms Law
- Watts Law
- Amps Law
4: What device should be used on low-temperature freezers?
- hot-gas by-pass
- high capacity TXV
- discharge muffler
- oil separator
5: What are the three components of a transformer?
- Primary core, secondary coil, and high and low voltage connectors.
- Contacts, secondary coil, and core
- Primary coil, secondary coil, and core
- Primary coil, secondary coil, and copper contacts
6: A hissing noise at the expansion valve is a good indication that
- gas is passing thru it
- nothing is passing thru
- liquid is passing thru it
- expansion valve is oversized
7: In a system designed for sub-zero ambient temperatures, what must be added?
- Infrared dye for leak identification
- Low-ambient kit
- Booster compressor
- Nitrogen
8: 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 aggregate of the high side and low side
- the high side
- the low side
- 2.5 times the design pressure
9: What is the refrigerant dichlorodifluoromethane?
- R-12
- R-134A
- R-22
- R-123
10: If a purge unit fails on a low pressure chiller, what are the symptoms?
- low pressure chillers do not have purge units
- low suction pressure
- increased capacity
- high head pressure
11: How many gallons of water per pound of ammonia do you need?
- 15
- 5
- 20
- 1
12: Who approves containers for refrigerants?
- D.O.D
- D.O.E
- E.P.A
- D.O.T
13: A relief valve discharge capacity is rated in
- PSIA
- Pounds of air per minute.
- temperature minus pounds of air per second divided by release rate squared
- PSIG
14: Which is the lowest vacuum?
- 5" hg
- 1,000 Microns
- 5 psig
- 10 psia
15: An azeotropic refrigerant is
- a mixture of two or more refrigerants that boil at about the same temperature minimizing temperature glide.
- a mixture of two or more refrigerants that boil at much different temperatures causing temperature glide
- a mixture of two or more refrigerants that boil at much different temperatures minimizing temperature glide
- none of the above
16: A run capacitor is wired in series with the _____ windings.
- common
- run
- start
- start capacitor
17: How many closing forces operate a thermostatic expansion valve?
- 4
- 1
- 2
- 3
18: Can you use Ammonia in industrial applications?
- When mixed with R-718
- Yes, Under certain condidtions
- Yes, always
- No, never
19: Ammonia shall be discharged into ____________ or a tank containing one gallon of water for every pound of ammonia.
- the atmosphere
- a de-pressurized recovery tank with a silver top and yellow bottom
- a tank containing two pounds of a water/lithium bromide mix for every pound of ammonia
- All of the above
20: Usually dry bulb temperature is
- higher than wet bulb temperature
- not important and shall be ignored
- same as wet bulb temperature
- lower than dry bulb temperature
21: NH3 is
- ammonia
- R-508A
- lithium bromide
- R-718
22: A pressure-limiting device isn't required on a factory-sealed system containing less than ____ lbs.
- 50
- 22
- 66
- 25
23: The leaving chilled water set point for comfort cooling is typically?
- 66
- 38
- 60
- 45
24: Transformers are rated in
- amps
- volt-amps
- volts-ohms
- volts
25: Refrigeration devices shall be equipped with a ____ to protect against unexpected pressure due to a malfunction or fire?
- T&P device
- Relief valve
- Temperature limiter device
- Circuit Breaker