Topics: All categories in the pool
1: What is not a requirement of a class T machine room?
- automatic ventilation
- fire hose connection to the building fire protection system
- tight fitting doors
- self-closing doors
2: Which of the following is an example of an azeotropic refrigerant?
- R-410A
- R-500
- R-134A
- R-404A
3: Ammonia systems use ____ pressure to adjust oil pressure
- stream
- air
- discharge
- liquid
4: Atmospheric pressure is equal to
- 29.92" Hg
- 14.7 psia
- 14.7 psig
- both a & b
5: R-410A is classified as a ____ refrigerant on the safety matrix.
- B-2
- A-2
- A-1
- B-1
6: The color code of a tank of ammonia is
- lavender
- silver
- light green
- white
7: One ton of refrigeration is defined as ______ btu/minute.
- 720,000
- 60
- 12,000
- 200
8: All low-pressure chillers use which type of compressor?
- Scroll
- Centrifugal
- Rotary
- Reciprocating
9: Heat transferred by conduction from one body to another is done via:
- gas
- liquid
- solid
- All of the above
10: Foaming of oil in a compressor is most likely to occur
- when ambient temperature are low
- at start-up
- when there is insufficient air across the condenser(i.e., dirty coil)
- when the evaporator temperatures are below 32F
11: 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)?
- printed circuit board (PCB)
- duel-voltage switch
- motor starter
- centrifugal switch
12: Which is considered the more efficient condenser?
- fan cooled
- air cooled
- spray cooled
- water cooled
13: 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.
- 350
- 50
- 550
- 100
14: 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
15: There can be no airflow from an occupied space through a machine room unless what?
- System is high velocity
- System is ducted and sealed
- Duct is not located in the ceiling
- None of the above.
16: Systems containing more than 110 pounds must have stop valves located at the
- compressor suction inlet
- compressor discharge outlet
- receiver inlet and outlet
- All of the above
17: Refrigerant systems containing Group I refrigerants can be installed in or on public stairways.
- True
- False
18: On a day with low relative humidity, the two thermometers on a sling psychrometer will read
- 2F difference
- far apart or greater difference
- a ling psychrometer doesn't have two theremometers.
- nearly the same
19: "P" represents ______ in the Watt's law formula
- amperage
- reactance
- voltage
- watts
20: Where is the high-side float located on a chiller system?
- flash line
- inside the chiller barrel
- discharge line
- liquid line
21: A rule of thumb in air conditioning is ____ CFM per ton?
- 400
- 600
- 500
- 100
22: A premise where large numbers of people congregate and from which occupants can not quickly vacate the space is considered
- institutional occupancy
- mixed occupancy
- public assembly occupancy
- commercial occupancy
23: Low-side system leaks in a low-pressure chiller will often result in
- system refrigerant leaking from the system
- nitrogen leaking out of the system.
- air being pulled into the system
- water being pulled into the system
24: All electrical work done on refrigeration systems must comply with
- NEC and Massachusetts Modifications
- OSHA
- Department of Energy
- ASHREA-15 Section 9.2.1
25: Refrigerants shall be classified by
- toxicity and flammability
- maximum permissible quantities of each group
- requirements for commercial, industrial, and residential occupancies
- color codes