Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: The purpose of a receiver is
a vessel to store refrigerant outside the system
to increase the capacity that the system can hold
to use a a later date
all of the above
2: Joints in refrigeration piping must be _____ before being covered?
Leak tested
Insulated
Inspected
Pressurized
3: A R-22 system running with a condensing temperature of 110F and a 40F evaporator temperature will read pressures of ____ on the high side and ____ on the low side.
455 psig, 185 psig
257 psig, 77 psig
226 psig, 68 psig
350 psig, 120 psig
4: NH3 is
ammonia
R-508A
lithium bromide
R-718
5: Copper and its alloys shall not be used with ammonia
True
False
6: While water is evaporated in an evaporative condenser the impurities which were in the water are
accumulate in the sump water
blown to the atmosphere by the fan
remain in the air
washed out of the air by the spray pump
7: Which refrigerant is lighter than air?
R-717
R-123
R-11
R-134a
8: Suction line oil traps should be installed when the condenser is
on the third floor roof and the evaporator is in the basement
in the basement and the evaporator is on the third floor
located outside the operates in temperatures below 35F
more than 100' away from the evaporator
9: 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
lift voltage
pick up voltage
run voltage
boost voltage
10: In designing duct work, pressure and ______ need to be considered
length
CFM
duct sealant used
all of the above
11: What would be the classification of a church?
Institutional
Industrial
Place of assembly
Large mercantile
12: Starting relays for a single phase compressors are used to remove the starting circuit from operation when the motor reaches approximately ____ percent of its speed.
50
100
24
75
13: Halo-carbon refrigerants cannot be used with what material?
Stainless Steel
Aluminum
Copper
Magnesium alloy
14: A class A3 refrigerant is considered
toxic and somewhat flammable
non-toxic but highly flammable
toxic and non-flammable
non-toxic and non-flammable
15: Which of the following are considered inorganic refrigerants?
R-717 and R-718
410A and R-407C
R-500 and R-502
None of the above
16: When liquid receivers are used, the liquid refrigerant shall not exceed _______percent of the volume at 90F.
75%
99%
90%
80%
17: B3 refrigerants are considered
non-toxic but flammable
non-toxic but non-flammable
toxic and highly flammable
toxic but non-flammable
18: What type of copper is not permitted on refrigeration systems?
Type M
Type L
Type N
Type K
19: Refrigerant is metered into the evaporator on a large centrifugal chiller thru the
low side of the system
high side float assembly
cap tube
none of the above
20: What is the amp draw of a 40 VA transformer at 24 volts
1,000 amps
106 amps
1K amps
1.6 amps
21: Ammonia shall be discharged into ____________ or a tank containing one gallon of water for every pound of ammonia.
the atmosphere
a de-pressurized recovery tank with a silver top and yellow bottom
a tank containing two pounds of a water/lithium bromide mix for every pound of ammonia
All of the above
22: With a 5/8" X 5/8" x 3/4" tee, what size is the center connection?
3/8"
5/8"
3/4"
1/2"
23: The location of a thermal bulb of a TXV affects
the amount of liquid returning to the compressor
the amount of liquid in the condenser.
subcooling
the amount of liquid refrigerant in the evaporator
24: Single compound Refrigerants are classified by what two criteria?
Temperature range and hazardousness
Flammability and toxicity
Weight and color
Flammability and temperature range
25: A mercury bulb controller is not recommended for