Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: On cooling towers, what causes the condenser water to drop
tower fans
ambient temperatures
evaporation of the water droplets
sensible heat
2: An oil pressure safety switch should be set at
5 to 10 psi below low side pressure
10 to 15 psi below low side pressure
10-15 psi above low side pressure
5 to 10 psi above low side pressure
3: A professional or office building would be considered what type of occupancy?
mercantile
commercial
business
public assembly
4: What type of material can't be used on the outlet of a relief valve?
Copper
Magnesium alloy
Stainless steel
PVC
5: Pressure-limiting device isn't required on a factory-sealed system containing less than ____ lbs.
50
33
18
22
6: What type of relief valve is used on low pressure centrifugal compressor systems?
Spring-loaded relief valve
Rupture disc
Purge relief
None of the above
7: A plug containing an alloy that will melt at a specific temperature to relief pressure is a
relief plug
fusion plug
rupture plug
fusible plug
8: A hotel is considered a _______ occupancy.
residential
commercial
institutional
mercantile
9: Which refrigerant is lighter than air?
R-11
R-134a
R-123
R-717
10: 1 Watt = ______ BTU's?
12
7.216
4.482
3.412
11: The maximum permissible amperage draw for a 40VA transfomer with a secondary voltage of 24V is
.1
1.7
.8
1.2
12: A halide torch is most useful with a freon compression system
to remove from from TXV's and evaporator coils
to detect refrigeration leaks in piping joints
to sweat flanges on the refrigeration piping
to release a sticking valve
13: The level of voltage caused by back electromagnetic force that opens the contacts of a potential relay in order to take the start capacitor out of the circuit is
boost voltage
lift voltage
pick up voltage
run voltage
14: Refrigerant restricted in 2004 but used for transition for decades:
R-134A
R-123
R-22
R-11
15: What is Absolute Zero?
-400F
-460F
-773F
-640F
16: Mercury was used in thermometers primarily because it
was inexpensive
expands uniformly
never freezes
vaporizes at very high temperatures
17: Brazed joints melt at temperatures above
1,000F
1,200F
500F
800F
18: On a large centrifugal system, what meters the flow to the evaporator?
Cap tube.
Low side float
TXV
High side float
19: At higher altitudes, the boiling point of refrigerant is
the same
higher
equal to the coefficient of water at 32F
lower
20: 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
21: Sensible heat is the heat added to a substance to
cause evaporation
change its state
freeze it
raise its temperature
22: Booster compressors connect to the ____ side of the compressor
oil side
low side
vapor
liquid
23: 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
24: The total amount of refrigerant stored in a machinery room in all containers not provided with relief valves shall not exceed
550 lbs
330 lbs.
660 lbs
55 lbs
25: On a day with low relative humidity, the two thermometers on a sling psychrometer will read
far apart or greater difference
2F difference
nearly the same
a ling psychrometer doesn't have two theremometers.