Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: The oil separator is always inserted in the system
in a cool spot
to prevent oil logging
in the discharge line
where it can be easily serviced
2: Ashrae states that the equipment on a building needs to conform to adjacent buildings classifications when within ____ feet from opening and intakes.
20
15
75
50
3: 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
4: In a low temperature refrigeration system, the benefit of the system using P.A.G. oil is
it is hydroscopic
it traps moisture
viscosity
all of the above
5: Which refrigerant replaced R-12?
R-407A
R-410A
R-22
R-134A
6: With a 5/8" X 5/8" x 3/4" tee, what size is the center connection?
3/8"
3/4"
1/2"
5/8"
7: Which occupancy can ammonia be used in?
depends on the quantity of freon
industrial
redifential
commercial
8: Name three things that must be done when changing refrigeration lubricant?
You can't change lubricants.
Nothing must be done
Place sign, check for leaks, insulate
Make sure it's compatible, notify owner, notify AHJ
9: What is used to check very low pressure?
Hygrometer
Velometer
Manometer
Hydrometer
10: Capacity control on a centrifugal compressor is accomplished by the
post-rotational guide vanes
slide vanes
pre-rotational guide vanes
check valves
11: A VRF system is a direct system
true
false
12: one BTU equals
31.4 hp
3.41 hp
12,000 hp
Pi
13: When a pressure gauge is permanently installed on a system, it must be ___ times the design pressure of the system.
1
2.2
1.2
1.5
14: Humidity can be sensed with
bimetal
pressure bellows
thermometer
human hair
15: There can be no airflow from an occupied space through a machine room unless what?
System is high velocity
System is ducted and sealed
Duct is not located in the ceiling
None of the above.
16: In a properly balanced system with valves open and properly adjusted, if the suction line is warm to the touch, its because of
moisture in the system
low head pressure
not enough oil in the system
oil in evaporator
17: 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
18: A total of all group A-2,B-2, A-3, and B-3 refrigerants shall not exceed ____ lb in the occupied areas and machinery rooms of institutional occupancies.
550
50
100
350
19: How far from the window does a relief valve need to be according to ASHRAE-15?
At least 30'
At least 20'
There is no minimum for relief valve and windows.
At least 40'
20: The gauge thickness required on a CO2 tank construction is
1/8"
5/16"
3/32"
1/16"
21: The equivalent length of pipe in a water piping system is
the total length of pipe plus equivalent-length of fittings
the total length of pipe as you would measure it
the total length of pipe as you would measure it plus 25% for fittigns
the total length of pipe plus equivalent of fittings multiplied by 2.31
22: Machinery rooms must be vented to ______?
unoccupied spaces
basement
outdoors
neutralizing tank
23: When releasing a hydrogenated hydrocarbon refrigerant to the atmosphere, ample ventilation must be provided and
gas masks must be worn
no flames shall be permitted
explosion precautions must be taken
the owner shall be informed
24: Setting a pressure relief device shall not exceed ___ of the design pressure
90%
80%
75%
100%
25: Where are the three places that the discharge from an ammonia relief valve be piped?
atmosphere, tank containing water, where the A.H.J. indicates