Topics: All categories in the pool
1: What must be done if refrigeration lines pass through a concrete floor?
- leak checked
- installed through a pipe casing
- insulated
- moisture barrier
2: An air conditioning system rated for 36,000 BTU's is equivalent to
- 12,000 tons of cooling
- two tons of cooling
- one ton of cooling
- three tons of cooling
3: Name a reason that does not cause reduced condenser air quantity
- Dirty Coil
- Dirty fan blades
- High ambient temperature
- Prevailing winds
4: 1 Watt = ______ BTU's?
- 3.412
- 12
- 7.216
- 4.482
5: Which is the lowest vacuum?
- 10 psia
- 5" hg
- 5 psig
- 1,000 Microns
6: The best way to detect ammonia in brine is
- CO2 gas
- carbonation of soda
- potassium of line
- nessler regaent
7: one BTU equals
- 3.41 hp
- Pi
- 31.4 hp
- 12,000 hp
8: When can 50/50 solder be used?
- in the low side
- in the high side
- liquid and suction lines
- none of the above.
9: Laten heat is associated with a change in state of a refrigerant but not temperature
- True
- False
10: If the dry bulb temperature is 85F and the wet bulb temperature is 70F, the dew point temperature will be approximately (use psychometric chart)
- 32F
- 58F
- 70F
- 77F
11: 746 watts is equal to
- 10 hp
- 1 hp
- 100 hp
- Pi
12: Foaming of oil in a compressor is most likely to occur
- when the evaporator temperatures are below 32F
- at start-up
- when ambient temperature are low
- when there is insufficient air across the condenser(i.e., dirty coil)
13: A compressor that increases vapor pressure by changing the internal volume of the compression chamber is called?
- Non-positive displacement
- Pressure induced displacement.
- Positive displacement
- Low Pressure displacement
14: What is the refrigerant chlorodifluoromethane?
- R-22
- R-123
- R-134a
- R-12
15: Pressure relief devices are marked with a ____________ signifying compliance with the ASME Boiler & Pressure Vessel Code.
- UM or UL
- UV or UR
- UL and UR
- UL and UM
16: R-123 belongs to Group
- B-2
- B-3
- A-3
- B-1
17: Evaporators within 18" of a heating coil must be equipped with a
- pressure relief device
- zone valve
- high limit control
- low limit control
18: Refrigerant restricted in 2004 but used for transition for decades:
- R-11
- R-123
- R-134A
- R-22
19: Booster compressors connect to the ____ side of the compressor
- oil side
- liquid
- vapor
- low side
20: Pressure vessels with an internal volume of 3 cubic feet or more
- shall use fusible plugs
- shall use pressure relief devices or fusible plugs
- shall use pressure relief devices
- do not need pressure relief protection
21: NH3 is
- lithium bromide
- R-508A
- ammonia
- R-718
22: What is the voltage of each leg to ground of a three-phase motor with a 460v supply voltage?
- 277v
- 240v
- 120v
- 208v
23: How is bring measured?
- hygrometer
- manometer
- hydrometer
- anemometer
24: Where are the three places that the discharge from an ammonia relief valve be piped?
- To chemical neutralizing tank only
- Underground, into drain, into mechanical room
- Atmosphere, Tank containing water, where the AHJ indicates.
- None of the above.
25: A Lithium-bromide system is an absorption system that
- uses ammonia as a refrigerant and lithium bromide as an absorbent
- uses water as a absorbent and lithium bromide as a refrigerant
- uses water as a refrigerant and lithium bromide as an absorbent
- uses salts as an absorbent and lithium bromide as a refrigerant