Topics: All categories in the pool
1: Which refrigerant(s) is an HFC?
- R-22
- R-410A
- R-502
- All of the above
2: Liquid shall not occupy more than ____ of the volume when the temperature of the refrigerant is 90F.
- 75%
- 100%
- 90%
- 80%
3: Pressure vessels with an internal volume of 3 cubic feet or more
- shall use pressure relief devices or fusible plugs
- do not need pressure relief protection
- shall use pressure relief devices
- shall use fusible plugs
4: A relief valve shall be located at least ___ above grade.
- 36'
- 15'
- 25'
- 10'
5: What is the typical air conditioning operating pressures for R-22?
- 60 psi suction 210 psi discharge
- 25 psi suction 125 psi discharge
- 105 psi suction 340 psi discharge
- None of the above
6: A chilled water pump suction gauge reads 10 psig. Discharge gauge reads 48 psig. The head in feet of the pump is working against
- 116
- 88
- 108
- 38
7: High pressure controls should be set no higher than
- 10% of set point
- 25% of set point
- 80% of set point
- 90% of set point
8: Viscosity is
- the coefficient of external friction
- a measure of heat content
- the ability of oil to flow
- measure of weight
9: On a single phase motor, when does the start winding cut out?
- Start windings do no cut-out of the run cycle
- At 75% of its full rated speed
- At 25% of its full rated speed
- At 50% of its full rated speed
10: Booster compressors, pump refrigerant into the
- heat & plate heat exchanges
- receiver
- low side of the primary compressor
- high side of the secondary compressor
11: Total heat of a substance is considered
- empathetical
- enthalpy
- sensible heat
- specific heat
12: An example of direct system is
- rooftop unit
- chiller
- absorber
- none of the above
13: Low pressure systems have what kind of compressor?
- Rotary
- Scroll
- Centrifugal
- Reciprocating
14: The high side float assembly meters refrigerant into the evaporator through the
- lower chamber of the low side
- upper chamber of the high side
- lower chamber of the high side
- upper chamber of the low side
15: Ammonia can come in contact with _______ ?
- Copper tubing
- Brass
- Copper
- Aluminum
16: The two basic types of evaporators are
- flooded and direct expansion
- prime surface and finned
- direct expansion and plate
- finned and plate
17: When can 50/50 solder be used?
- in the low side
- in the high side
- liquid and suction lines
- none of the above.
18: Horizontal piping should be run level.
- False
- Yes, if the condenser is located above the evaporator
- No, unless the supervisor on the job says so.
- True
19: Absolute pressure is
- Gauge Pressure
- Atmospheric Pressure
- Gauge + Atmospheric Pressure + Pi
- none of the above
20: Where are the three places that the discharge from an ammonia relief valve be piped?
- atmosphere, tank containing water, where the A.H.J. indicates
- underground, into drain, into mechanical room
- to chemical neutralizing tank only
- none of the above
21: What is the maximum voltage range allowed on an electrical circuit?
- 5%
- 15%
- 20%
- 10%
22: The rupture disc on a low-pressure chiller typically releases pressure at
- 0 psig
- 5 psig
- 15 psig
- 10 psig
23: A hotel is considered a _______ occupancy.
- residential
- institutional
- commercial
- mercantile
24: According to ASHRAE Standard-15 9.8 Positive Displacement Compressor Protection, the pressure-relief device discharge into
- the low-pressure side of the system
- the high side of the system
- the liquid receiver
- both a and c are correct
25: Thermodynamics is the branch of science that deals with
- state of energy
- energy due to motion
- molecular therory
- heat energy