Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: Refrigerant restricted in 2004 but used for transition for decades:
R-22
R-123
R-11
R-134A
2: A line voltage thermostat controls a 1,200 watt strip header at 120 volts. What must be minimum ampere rated of the stat be?
15 amps
10 amps
5 amps
20 amps
3: Transformers are rated in
volts-ohms
amps
volt-amps
volts
4: Which of the following controllers would you expect to be most sensitive to temperature changes?
immersion controller
low voltage t-stat
aquastat
line voltage t-stat
5: What type of fuses must be used on a HVAC system?
TR Type, Duel Element, Time Delay
Fast blow
10% lower than RLA
none of the above
6: Laten heat is associated with a change in state of a refrigerant but not temperature
True
False
7: Which creates more of a heat load?
90% RH
70% RH
30% RH
50% RH
8: In a system designed for sub-zero ambient temperatures, what must be added?
Booster compressor
Infrared dye for leak identification
Nitrogen
Low-ambient kit
9: A factory-sealed system containing less than 22lbs. of Group A1 refrigerant
shall have a pressure limiting device installed on the high side of the system
shall be inspected by the Boiler of Inspectors bi-annually
shall have a pressure limiting device and a pressure relief valve installed
does not require a pressure-limiting device
10: A plug containing an alloy that will melt at a specific temperature to relief pressure is a
rupture plug
fusion plug
relief plug
fusible plug
11: A declaration test is needed when the system contains more than
65 lbs
110 lbs
120 lbs
55 lbs
12: 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
13: How are refrigerant blends classified?
Blends don't have to be classified
Based on worst case fractionation
Based on best case Fractionation
Based on the oil used
14: Materials used in construction and installation materials used in the manufacture or installation of refrigerating equipment shall be suitable for conveying refrigerant and the refrigerant oils and will not deteriorate in the presence of what?
Moisture and air
Oil and water
Water and soap
Air and dirt
15: Pressure is equivalent of
Force / Area
Force X Area
Force
Area X Force
16: Joints in piping for refrigeration containing parts must withstand temperatures of ___?
800F
700F
1000F
600F
17: Which of the following is an inorganic refrigerant?
R-22
Ammonia
Chlorofluorocarbons
All of the above
18: Ammonia (NH3) is a group III refrigerant
True
False
19: What must be done to refrigerant pipes before being buried ?(8.10.4)
Leak checked
Classifed
Certified
Insulated and installed in a pipe duct (Encased)
20: After setting up a forward curved fan for the desired conditions, something happened to lower the total static pressure the fan had to operate against. Which would occur?
CFM and RPM decrease
CFM and HP increase
RPM and CFM increase
CFM and HP decrease
21: The 4 basic methods of determining whether the proper amount of refrigerant is being introduced into the system are
sight glass, weight, pressure, and frost line
Buss-eye, weight, pressure, and frost line
sight glass, weight, pressure, and dipstick
sight glass, weight, paper method, and frost line.
22: A water regulating valve opens when
the head pressure rises
when the power is on
the compressor is on
when the power is on there is an overcharge of refrigerant
23: How many different groups of refrigerants are there?
15
3
7
11
24: How much clearance do you need around the perimeter of electrical panels?
18"
12"
36"
24"
25: The ____ design is the maximum pressure for which a specific part of a refrigeration system is designed.