Topics: All categories in the pool
1: Setting a pressure relief device shall not exceed ___ of the design pressure
- 80%
- 90%
- 100%
- 75%
2: The formula for Pure Power in a resistance circuit is
- Kw = volts X amps
- Watts = volts X amps
- Watts X amps.
- Watts X power factor
3: A capacitor in series with the start windings will do what?
- Increase starting torque
- Increase run efficiency by 10% of its rating
- Decrease the RLA to within 10% of its rating
- Nothing
4: An air conditioning system rated for 36,000 BTU's is equivalent to
- three tons of cooling
- 12,000 tons of cooling
- two tons of cooling
- one ton of cooling
5: Which refrigerant replaced R-12?
- R-134A
- R-410A
- R-407A
- R-22
6: A room having machinery but no flame producing apparatus permanently installed and operated is considered a
- Class A machinery room
- Class B machinery room
- Class M machinery room
- Class T machinery room
7: On a day with low relative humidity, the two thermometers on a sling psychrometer will read
- far apart or greater difference
- a ling psychrometer doesn't have two theremometers.
- 2F difference
- nearly the same
8: How many different groups of refrigerants are there?
- 3
- 11
- 15
- 7
9: A class B1 refrigerant is considered
- toxic and somewhat flammable
- toxic but non-flammable
- non-toxic and non-flammable
- non-toxic but highly flammable
10: What is a Category "D" fluid?
- Any fluid that exceeds 150 psig and has design temperature of over 366F
- A toxic fluid, which can produce serious irreversible harm to persons on breathing or bodily contact
- A typical refrigerant used on newer air conditioning and heat pump ssytems
- A fluid which is nonflammable, nontoxic, not damaging to human tissues, does not exceed 150 psig, and design temperature is between -20F to 366F
11: The two basic types of evaporators are
- direct expansion and plate
- flooded and direct expansion
- prime surface and finned
- finned and plate
12: 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
- 75
- 55
- 15
13: Where is the high-side float located on a chiller system?
- inside the chiller barrel
- discharge line
- liquid line
- flash line
14: Heat transferred by conduction from one body to another is done
- via solids
- via liquids
- via radiation
- via heat rays
15: "R" represents ___ in the Ohm's law formula
- amperage
- resistance
- capacitance
- voltage
16: R-410A can segregate in the system or chemically change its composition due to a leak.
- True
- False
17: 1 Watt = ______ BTU's?
- 3.412
- 12
- 7.216
- 4.482
18: What device should be used on low-temperature freezers?
- high capacity TXV
- discharge muffler
- hot-gas by-pass
- oil separator
19: How do you find net oil pressure on a compressor?
- discharge pressure - suction pressure
- gross oil pressure - suction pressure
- gross oil pressure - discharge pressure
- all of the above
20: A cross charged power element on an expansion valve would normally be used in what temperature range?
- -100F to -40F
- 30F to 50F
- -40F to 0F
- 0F-38F
21: Pressure vessels with an internal volume of 3 cubic feet or more
- do not need pressure relief protection
- shall use fusible plugs
- shall use pressure relief devices or fusible plugs
- shall use pressure relief devices
22: If the spring is adjusted to increase the superheat, this new setting will
- have no effect on the frost line
- lengthen the frost line
- allow more liquid into the evaporator
- shorten the frost line
23: Ammonia (NH3) is a group III refrigerant
- True
- False
24: The outer portion of shell of the compressor used on low-pressure chillers is called the
- suction
- nozzle
- baffle
- volute
25: At higher altitudes, boiling temperatures
- depends on the refrigerant
- decrease
- increase
- are unaffected