Topics: All categories in the pool
1: Direct systems using Group II refrigerants
- shall not be used for air condition for human comfort
- shall be allowed to be used for human comfort.
- shall be installed in Class T machinery rooms
- shall be installed per instruction of the AHJ
2: In a properly balanced system with valves open and properly adjusted, if the suction line is warm to the touch, its because of
- low head pressure
- not enough oil in the system
- moisture in the system
- oil in evaporator
3: Absolute pressure is
- Gauge Pressure
- Atmospheric Pressure
- Gauge + Atmospheric Pressure + Pi
- none of the above
4: R22 and 410A operate at the same range of condensing and evaporating temperatures
- true
- false
5: What must be done to all doors and access points in duct work going through a mechanical room?
- Must be hindged
- Must be screwed shut
- Must be sealed and gasketed
- All of the above
6: When a refrigerating machinery room is used, the emergency procedures shall be posted
- on a conspicuous card located near the evaporator
- on a conspicuous card located near the compressor
- outside the room, immediately adjacent to each door
- inside the room, immediately adjacent to each door
7: Large Mercantile occupancy is a premise or that portion of a premise where more than ____ persons congregate on levels above or below the street level to purchase personal merchandise.
- 100
- 250
- 400
- 350
8: Brazed joints melt at temperatures above
- 1,000F
- 800F
- 1,200F
- 500F
9: What happens to copper joints when overheated?
- nothing
- joint becomes oxidized and ditorted
- copper becomes harder
- none of the above
10: What instrument is used to measure very high resistance?
- ammeter
- voltmeter
- tape measure
- meg ohmmeter
11: What would be the classification of a church?
- Place of assembly
- Industrial
- Large mercantile
- Institutional
12: Lithium-bromide, Li-Br, is best characterized as a
- sugar
- soil
- salt
- sand
13: Three-phase motors have what type of windings?
- three run windings
- one start winding and one run winding.
- three run windings and 3 start windings
- three start windings
14: 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
15: Indirect systems using Group II refrigerants
- shall be used in refrigeration system less than 1,000 lbs
- shall be used in refrigeration system in excess of 1,000 lbs
- shall have all refrigerant containing parts except piping, installed in a Class T machine room
- shall be used for mechanical equipment only
16: What device should be used on low-temperature freezers?
- discharge muffler
- high capacity TXV
- oil separator
- hot-gas by-pass
17: Fusible plugs shall not be used with pressure vessels of
- 15 cubic feet or more
- 3 cubic feet or less
- 15 square feet or less
- 3 cubic feet or more
18: Before you change the type of refrigerant in a refrigeration system, what three things must be done?
- nothing must be done
- place sign, check for leaks, insulate
- make sure it's compatible, notify owner, notify A.H.J
- you can't change refrigerants
19: The equivalent length of pipe in a water piping system is
- the total length of pipe plus equivalent of fittings multiplied by 2.31
- the total length of pipe as you would measure it plus 25% for fittigns
- the total length of pipe as you would measure it
- the total length of pipe plus equivalent-length of fittings
20: The amount of heat required to raise the temperature of 1 lb of water 1F is?
- 1 Kelvin
- 1 BTU
- The rate of conduction
- 1 Therm
21: System design pressures must take into consideration, not only, pressures found during normal operation but also what?
- When it's cold out
- When there is a malfunction on the high side
- When its warm out
- All of the above
22: RPM's of a centrifugal compressor are at approximately?
- 500
- 10,000
- 15,000
- 30,000
23: Refrigerants shall be classified by
- requirements for commercial, industrial, and residential occupancies
- toxicity and flammability
- maximum permissible quantities of each group
- color codes
24: What device removes the start winding from the circuit of a split-phase motor once the motor reaches 75% of its rated load amps (RLA)?
- motor starter
- printed circuit board (PCB)
- duel-voltage switch
- centrifugal switch
25: Which of the following types of oils are hygroscopic?
- polyolester (POE)
- polyalkylene glycol (PAG)
- naphthene mineral
- both a and b