Topics: All categories in the pool
1: What is absolute humidity?
- the amount of moisture in the air per one pound of 50% RH air
- the amount of moisture in the air in grains of cubic feet of volume
- the amount of moisture in the air in grains of square feet of volume
- none of the above
2: Heat transferred by conduction from one body to another is done via:
- gas
- liquid
- solid
- All of the above
3: Refrigerants shall be classified by
- toxicity and flammability
- maximum permissible quantities of each group
- color codes
- requirements for commercial, industrial, and residential occupancies
4: The boiling point of a refrigerant is based on
- Temperature
- Heat content
- a pressure-temperature relationship
- None of the above.
5: An electrical circuit has a 208V power supply and draws 47 amps total, What would be the wattage of the circuit
- .9776 watts
- 9,776 watts
- 9.776 watts
- 977.6 watts
6: The main cause of enacting the "no vending rule" of July 1st 1992 was
- global warming potential
- ozone depletion
- both a & b
- None of the above
7: Which oil is hydoscopic?
- animal
- SW30
- polyolester
- mineral
8: An example of direct system is
- rooftop unit
- chiller
- absorber
- none of the above
9: On a day with low relative humidity, the two thermometers on a sling psychrometer will read
- nearly the same
- 2F difference
- far apart or greater difference
- a ling psychrometer doesn't have two theremometers.
10: When the compressor is below the condensor
- traps are needed on the suction line
- traps are needed on the oil return line
- traps are needed on the discharge line
- traps are not needed on this type of system
11: When an electronic bridge is in balance the bridge output will be
- 0 volts
- 1 volt
- .01 volts
- 15 volts
12: Ohm's Law indicates Amps X Resistance = ___________.
- Current
- Impedance
- Ohms
- Volts
13: On a single phase motor, when does the start winding cut out?
- At 50% of its full rated speed
- At 25% of its full rated speed
- At 75% of its full rated speed
- Start windings do no cut-out of the run cycle
14: How many gallons of water per pound of ammonia do you need?
- 5
- 20
- 1
- 15
15: A Lithium-bromide system is an absorption system that
- uses water as a absorbent and lithium bromide as a refrigerant
- uses ammonia as a refrigerant and lithium bromide as an absorbent
- uses salts as an absorbent and lithium bromide as a refrigerant
- uses water as a refrigerant and lithium bromide as an absorbent
16: What do you need to do when you install a new system?
- Have it inspected
- Document the superheat and subcooling reading
- Insulate the suction line before you take a superheat reading
- Add refrigerant
17: A movie theater would be considered a
- commercial occupancy
- mixed occupancy
- public assembly occupancy
- institutional occupancy
18: Mercury was used in thermometers primarily because it
- vaporizes at very high temperatures
- never freezes
- expands uniformly
- was inexpensive
19: What is the minimum height refrigeration piping should be placed against walls?
- 7.25'
- 72"
- Ceiling height
- 6'
20: Which refrigerant is lighter than air?
- R-134a
- R-123
- R-11
- R-717
21: While water is evaporated in an evaporative condenser the impurities which were in the water are
- accumulate in the sump water
- remain in the air
- washed out of the air by the spray pump
- blown to the atmosphere by the fan
22: What is used to check very low air pressures in air conditioning duct?
- Barometer
- Manometer
- Vacuum gauge
- Anemomter
23: Which occupancy can ammonia be used in?
- commercial
- industrial
- depends on the quantity of freon
- redifential
24: The amount of heat required to raise the temperature of 1 lb of water 1F is?
- 1 Therm
- 1 Kelvin
- The rate of conduction
- 1 BTU
25: All welding done on any refrigeration system or piping covered by 522 CMR 9.00 shall be performed by a according to Section IX of the ASME code
- competent welder
- licensed welder
- licensed technician
- welder qualified