Topics: All categories in the pool
1: What is the amp draw of a 40 VA transformer at 24 volts
- 1K amps
- 1.6 amps
- 1,000 amps
- 106 amps
2: What is a megaohm meter?
- An electric meter that measures very high resistance values by sending a low voltage AC signal into the object being tested
- An electric meter that measures very high resistance values by sending a high DC voltage signal into the object being tested
- Is an electric meter that measures extremely low resistance valves by sending high DC voltage signal into the object being tested.
- An electric meter used by electricians to test large 3-phase blower motors for the correct rotation
3: A relief valve discharge capacity is rated in
- PSIA
- temperature minus pounds of air per second divided by release rate squared
- Pounds of air per minute.
- PSIG
4: When liquid receivers are used, the liquid refrigerant shall not exceed _______percent of the volume at 90F.
- 90%
- 80%
- 99%
- 75%
5: Three-phase motors have what type of windings?
- one start winding and one run winding.
- three start windings
- three run windings and 3 start windings
- three run windings
6: If two 500 ohm resistors are connected in series, the resistance will be
- 500 ohms
- 20 ohms
- 1000 ohms
- 200 ohms
7: Increasing superheat will do what to your frost line?
- Increasae
- Could either increase or decrease depending on the load conditions
- Decrease
- Nothing
8: Foaming of oil in a compressor is most likely to occur
- at start-up
- when the evaporator temperatures are below 32F
- when ambient temperature are low
- when there is insufficient air across the condenser(i.e., dirty coil)
9: Fusible plugs shall not be used with pressure vessels of
- 15 square feet or less
- 3 cubic feet or more
- 3 cubic feet or less
- 15 cubic feet or more
10: Which of the following types of oils are hygroscopic?
- polyolester (POE)
- polyalkylene glycol (PAG)
- naphthene mineral
- both a and b
11: An example of an "Expendable Refrigerant" is
- ammonia
- lithium bromide
- liquid nitrogen
- liquid oxygen
12: A High-Probability System
- is such that a leak of refrigerant from a failed connection will enter the occupied space
- is such that any leak will cause injury or death to anyone within a 100 square foot area
- is such that a leak of refrigerant from a failed connection will enter an unoccupied space
- is a system highly likely to leak form a failed connection or component of such system
13: Liquid refrigerant R-22 enters an evaporator at 50.2 psig, 20F and leaves 37F, its pressure as it leaves will be
- 66.1 psig
- 70.8 psig
- 43.3 psig
- 50.2 psig
14: The total amount of refrigerant stored in a machinery room in all containers not provided with relief valves shall not exceed
- 550 lbs
- 660 lbs
- 330 lbs.
- 55 lbs
15: On a day with low relative humidity, the two thermometers on a sling psychrometer will read
- far apart or greater difference
- a ling psychrometer doesn't have two theremometers.
- 2F difference
- nearly the same
16: One ton of refrigeration is defined as ______ btu/minute.
- 720,000
- 200
- 12,000
- 60
17: It takes how many BTU/hr to melt one pound of ice at 32F
- 212
- 180
- 144
- 970
18: Single compound Refrigerants are classified by what two criteria?
- Weight and color
- Flammability and toxicity
- Flammability and temperature range
- Temperature range and hazardousness
19: When an inspection is needed, how often must it be done?
- every 18 months
- every 36 months
- annually
- every 24 months
20: NH3 is
- ammonia
- lithium bromide
- R-718
- R-508A
21: A start capacitor is wired in _____ with the start windings.
- series
- junction
- series-parallel
- parallel
22: A low oil switch is typically
- time-delay auto reset
- manual reset
- automatic reset
- non used on semi-hermetic compressors over 10 ton capacity
23: What refrigerant were phased out in 2004?
- R-11
- R-134a
- R-12
- R-22
24: Which refrigerant is lighter than air?
- R-134a
- R-11
- R-123
- R-717
25: A normally operating R-410A system with a condensing temperature of 110F will have a high side pressure of around ______ psig
- 125 psig
- 327 psig
- 365 psig
- 255 psig