Topics: All categories in the pool
1: How are safety controls wired in a circuit?
- Either series or parallel
- Series
- Series/parallel
- Parallel
2: The Department that certifies the transportation of refrigerant is the
- RSES
- DOT
- EPO
- EPA
3: A motor starter is a device that includes an overload and a _______?
- contactor
- 2-pole contacts
- duel-coil
- all of the above
4: A run capacitor is wired in series with the _____ windings.
- run
- common
- start
- start capacitor
5: A mercury bulb controller is not recommended for
- line voltage use
- use where vibration is severe
- line or low voltage use
- low voltage use
6: Thermodynamics is the branch of science that deals with
- heat energy
- state of energy
- energy due to motion
- molecular therory
7: Fusible plugs shall not be used with pressure vessels of
- 3 cubic feet or less
- 15 square feet or less
- 15 cubic feet or more
- 3 cubic feet or more
8: Large mercantile occupancy is
- a premise of that portion of a premise where more than 100 persons congregate on levels above of below street level to purchase personal merchandise.
- a premise of that portion of a premise where more than 50 persons congregate on levels above of below street level to purchase personal merchandise.
- a premise or that portion of a premise where more than 200 persons congregate on levels above or below street level to purchase personal merchandise
- a premise or that portion of a premise where more than 1500 persons congregate on levels above or below street level to purchase personal merchandise
9: A normal operating evaporator temperature of R-22 for air conditioning is typically
- 58F
- 45F
- 55F
- 32F
10: Oils, classified as to source, are
- naphthalene, mixed, and paraffin
- animal, vegetable, and mineral
- naphthalene, paraffin, and castor
- animal, vegetable, and castor
11: Liquid refrigerant R-22 enters an evaporator at 50.2 psig, 20F and leaves 37F, its pressure as it leaves will be
- 50.2 psig
- 66.1 psig
- 70.8 psig
- 43.3 psig
12: Pi equals approximately
- 3.14
- 746
- 3.41
- 12,000
13: Which creates more of a heat load?
- 30% RH
- 50% RH
- 90% RH
- 70% RH
14: A micron is
- one millonths of a centimeter
- a larger unit of measurement than Hg
- one millonths of a micrometer
- one thousandths of a millimeter
15: On a TXV, the purpose of an external equalizer is to?
- Increase the pressure on the top of the power head diaphragm
- allow a greater adjustment spam
- balance the evaporator load
- compensate for a pressure drop across the evaporator coil
16: When is the only time you can leave a service container attached to a system?
- Leaking system
- Recovery
- Charging
- Both b and c
17: One ton of refrigeration is defined as ______ btu/minute.
- 60
- 200
- 720,000
- 12,000
18: Liquid refrigerant flashing, or turning to vapor, in the liquid line may be due to
- liquid line that is too small
- shortage of refrigerant
- liquid line that had too high vertical lift
- All of the above
19: A class B2 refrigerant is considered
- non-toxic and highly flammable
- toxic and non-flammable
- toxic and somewhat flammable
- non-toxic and non-flammable
20: What is a Category "M" fluid?
- A typical refrigerant used on newer air conditioning and heat pump systems
- Any fluid that exceeds 150 psig and has design temperatures over 366F
- A fluid which is nonflammable, nontoxic, not damaging to human tissues, does not exceed 150 psig, and the designed temperature is between -20F to 366F
- A toxic fluid, which can produce serious irreversible harm to persons on breathing or bodily content
21: Refrigerant systems containing Group I refrigerants can be installed in or on public stairways.
- True
- False
22: Foaming of oil in a compressor is most likely to occur
- at start-up
- when the evaporator temperatures are below 32F
- when there is insufficient air across the condenser(i.e., dirty coil)
- when ambient temperature are low
23: If a liquid receiver is designed to receive the refrigerant charge during a pumpdown procedure, it shall have the capacity to
- receive the pumpdown charge
- hold up to 110% of the pumpdown charge
- Pumpdown procedures are not allowed with systems containing liquid recievers
- release the charge when the pressure exceeds 310 psig or higher
24: Gauge pressure is
- atmospheric pressure
- what a gauge reads when checking pressures on a chilled water system.
- absolute pressure
- force of pressure above that of atmospheric
25: Heat transferred by conduction from one body to another is done via:
- gas
- liquid
- solid
- All of the above