Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: What device measures the specific gravity of a substance?
Hydrometer
Manometer
Thermometer
Hygrometer
2: What must be done if refrigeration lines pass through a concrete floor?
insulated
installed through a pipe casing
moisture barrier
leak checked
3: The critical temperature of a refrigerant gas occurs when
the gas is no longer saturated
any decrease in pressure will cause condensation
the gas returns to a liquid
any increase in pressure will not liquefy the gas
4: If a purge unit fails on a low pressure chiller, what are the symptoms?
high head pressure
low suction pressure
low pressure chillers do not have purge units
increased capacity
5: 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
6: How many square inches per square foot?
64
144
98
24
7: A room having machinery but no flame producing apparatus permanently installed and operated is considered a
Class A machinery room
Class B machinery room
Class T machinery room
Class M machinery room
8: Ammonia belongs to Group
A-1
A-2
B-1
B-2
9: A hotel is considered a _______ occupancy.
institutional
residential
mercantile
commercial
10: The certificate of inspection
shall be authorized by a notarized insurance company
shall be posted and protected from dirt, water, and other elements
shall be $20 and an additional fee of $1 for each tone above 20 tons
shall be posted on the compressor shell or electrical panel at the unit
11: A thermometer inside a duct measures ____ heat.
sensible
hidden
specific
latent
12: pressure relief valves must discharge to the atmosphere at a location not less than 15 feet from ground level and ____ feet from any window, ventilation opening, or exits of buildings.
10
20
25
15
13: At higher altitudes, boiling temperatures
increase
decrease
depends on the refrigerant
are unaffected
14: In an air conditioning plant which an indirect low side, water is used inside of bring: the proper sequence of operating the plan is
reset the safety valve
start the fan and circulating pump
reset the expansion valve
start the comrpessor
15: Pressure is equivalent of
Force
Force / Area
Force X Area
Area X Force
16: How many groups of refrigerants are there?
3
1
7
5
17: If the power element of an expansion valve should lose its charge the valve would
underfeed the evaporator
overfeed the evaporator
go open
go closed
18: Low pressure chiller systems use what type of compressor?
Scroll
Centrifugal
Reciprocating
Screw
19: If air is present in an absorption chilled water appliance, which of the following will most likely occur?
The Li-Br solution will become more concentrated
System operating pressure will drop
Rust can form
The Li-Br solution will become more diluted
20: 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.
21: Capacitors are rated in
micro-farads
megaohms
volt - amperes
kelvins
22: What refrigerant doesn't have to be classified?
R-717
R-718
R-422A
R-134A
23: How many gallons of water do you need per pound of ammonia?
1
50
10
100
24: Name a CFC refrigerant(s):
R-11
R-12
R-123
both a & b
25: The critical temperature of a refrigerant gas occurs when