Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: R-717 is
water
ammonia
trichloromethane
carbon dioxide
2: If the suction pressure is low and the evaporator temperature high, the cause will be a?
overcharged
starved evaporator
too small evaporator
compressor suction valve stuck open
3: Lithium-bromide, Li-Br, is best characterized as a
soil
salt
sugar
sand
4: Name a reason that does not cause reduced condenser air quantity
Prevailing winds
Dirty fan blades
High ambient temperature
Dirty Coil
5: "P" represents ______ in the Watt's law formula
watts
reactance
voltage
amperage
6: When releasing a hydrogenated hydrocarbon refrigerant to the atmosphere, ample ventilation must be provided and
gas masks must be worn
explosion precautions must be taken
no flames shall be permitted
the owner shall be informed
7: What refrigerant has zero ozone depletion
HFC
CFC
HCFC
None of the above
8: Dew point is
the temperature above which water vapor in the air will start to condense
the temperature below which water vapor in the air will start to condense
the temperature below which water vapor in the air will start to evaporate
the temperature of air of 50% RH
9: The solution that is pumped into the concentrator in an absorption chiller is referred to as the
strong solution
absorbed solution
concentrated solution
weak solution
10: How can you test mechanical strength of an electrical connection?
measure ohms with an electrical meter
measure voltage across the connection
attempt to pull the wire from the connector by hand
none of the above.
11: A Category D fluid
is when the fluid handled is non flammable, nontoxic, and not damaging to human as defined in ANSI/ASME Process Piping.
is when the design pressure does not exceed 150 psi
a fluid for service piping in which the potential for personnel exposure is judged to cause harm and irreversible damage to those persons exposed to it
Both a and b are correct
12: 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.
400
100
350
250
13: Machinery rooms shall be vented to _____________ and utilizing mechanical ventilation.
the outdoors
Machinery rooms need not be vented
the return air ducted system
the mechanical room housing the refrigeration system
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: Industrial occupancy is
a premise or that portion of a premise that is not open to the public, where access by authorized persons is controlled, and that is used to manufacture, process, or store goods, such as chemicals, food, ice, meat, or petroleum.
is a premise or that portion of a premise where large number of people congregate and from which occupants cannot quickly vacate the space.
a premise or that portion of a premise where people transact business, receive personal service, or purchase food and other goods.
Both a and b are correct
16: What is the minimum height refrigeration piping should be placed against walls?
7.25'
72"
Ceiling height
6'
17: Single compound Refrigerants are classified by what two criteria?
Flammability and temperature range
Temperature range and hazardousness
Flammability and toxicity
Weight and color
18: The dry bulb temperature at 90F and a wet bulb temperature of 65F there will be approximately _____ grains/lb. of moisture in the air. (use psychometric chart)
46
77
54
34
19: Heat transferred by conduction from one body to another is done ia:
gas
liquid
solid
All of the above
20: Pressure vessels having design pressures of 15 psig or less shall have the strength to withstand at least ______times the design pressure.
3.0
5.5
2.0
2.5
21: In a system designed for sub-zero ambient temperatures, what must be added?
Low-ambient kit
Booster compressor
Nitrogen
Infrared dye for leak identification
22: When systems are protected by a high pressure relief device, the compressor's pressure limiting device shall be set at or below ____ % of the operating pressure of the high side relief device.
100
110
80
90
23: Increasing superheat will do what to your frost line?
Increasae
Decrease
Nothing
Could either increase or decrease depending on the load conditions
24: Pressure vessels with an internal volume of 3 cubic feet or less
shall use pressure relief devices or fusible plugs