Topics: All categories in the pool
1: Which has more turns in the windings: Start windings or Run windings?
- Start windings
- Run windings
- They both have the exact same turns
- Depends on the system and capacitor used
2: A total of all group A-2,B-2, A-3, and B-3 refrigerants shall not exceed ____ lb in the occupied areas and machinery rooms of institutional occupancies.
- 550
- 350
- 50
- 100
3: A device used to measure small pressure differences is the
- anemometer
- pyrometer
- manometer
- phsycometirc
4: Pressure vessels having an inside diameter of 6” or less shall be protected by
- either a fusible plug or a pressure relief device
- Pressure vessels having an inside diameter of 6” or less need no such protection unless otherwise specified
- a fusible plug
- a pressure relief device
5: Where can 50/50 solder be used on?
- suction line
- liquid line
- discharge line
- none of the above
6: The actual expansion curve of compressor follows most nearly which one of the following
- Pressure-Temperature
- Volume
- Isothermal
- Adiabatic
7: Mercury was used in thermometers primarily because it
- expands uniformly
- was inexpensive
- never freezes
- vaporizes at very high temperatures
8: While the system is operating, the discharge line should be
- too hot to hold by hand
- room temperature
- at the same temperature as the crankcase
- 10-15F warmer than ambient
9: How is bring measured?
- anemometer
- hydrometer
- hygrometer
- manometer
10: Sensible heat is the heat added to a substance to
- freeze it
- raise its temperature
- change its state
- cause evaporation
11: Ammonia systems use ____ pressure to adjust oil pressure
- discharge
- air
- stream
- liquid
12: Pressure relief devices are marked with a ____________ signifying compliance with the ASME Boiler & Pressure Vessel Code.
- UV or UR
- UM or UL
- UL and UR
- UL and UM
13: Who authorizes changes to the safety codes?
- Board of Boilers
- Contractor who last serviced the system.
- Person who pulled the permit
- Person in charge of the facility
14: Where is the high-side float located on a chiller system?
- inside the chiller barrel
- flash line
- discharge line
- liquid line
15: What is the temperature that a liquid and a vapor can exist in equilibrium called?
- Wet bulb temperature
- Dry bulb temperature
- Critical temperature
- Saturated temperature
16: When should a relief valve start to function?
- Before the purge station discharges
- At it's set pressure
- Two times it's working pressure
- 10 psi before it's set pressure
17: Direct systems using Group II refrigerants
- shall not be used for air condition for human comfort
- shall be installed in Class T machinery rooms
- shall be installed per instruction of the AHJ
- shall be allowed to be used for human comfort.
18: Oils, classified as to source, are
- animal, vegetable, and mineral
- naphthalene, paraffin, and castor
- naphthalene, mixed, and paraffin
- animal, vegetable, and castor
19: What is the leaving chilled water set point for water chiller systems?
- 38F
- 66F
- 55F
- 45F
20: High side floats are used on centrifugal chiller systems are are considered critically charged systems.
- are obsolete.
- True
- False
- depends on the type of refrigerant being used
21: The reversing valve is commonly used
- when the code requires a check valve
- on multiple compressor systems
- on all heat pumps
- on commercial system that involve two different temperatures
22: A chilled water pump's suction gauge reads 10 psig. The discharge gauge reads 48 psig. What is the head in feet the pump is working against?
- 38
- 96
- 88
- 58
23: When a pressure gauge is permanently installed on a system, it must be ___ times the design pressure of the system.
- 1
- 1.2
- 1.5
- 2.2
24: Pressure vessels with an internal volume of 10 cubic feet or more
- shall use pressure relief devices
- shall use pressure relief devices or fusible plugs
- shall use rupture discs or duel pressure relief valves
- shall use fusible plugs
25: When a refrigeration or air conditioning system is installed
- the form of certificate shall be authorized by the Department of Pubic safety
- it shall be approved by the owner for proper operation.
- a field inspection shall be made before it is put into service
- it shall not be operated below prescribed pressures