Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: If a halide torch is used for leak detection, what color is the flame if it detects a leak?
blue
green
orange
red
2: The heat picked up in the evaporator must equal to
the heat giving by the condenser
the heat of compression
the heat lost by the medium being cooled
the heat gained by the condenser
3: Halogenated refrigerants cannot be used with what material?
Aluminum
Stainless steel
Magnesium alloy
Copper
4: The location of a thermal bulb of a TXV affects
the amount of liquid returning to the compressor
subcooling
the amount of liquid in the condenser.
the amount of liquid refrigerant in the evaporator
5: 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
Rust can form
System operating pressure will drop
The Li-Br solution will become more diluted
6: How much refrigerant can be stored in a mechanical room outside of the system?
200
100
150
330
7: Two systems using separate refrigerants that are superimposed upon one another is called
indirect
booster
cascade
single stage
8: Which is considered the more efficient condenser?
air cooled
spray cooled
fan cooled
water cooled
9: How many CFMs are required per square foot of commercial office occupied space
5 CFM
20 CFM
15 CFM
.5 CFM
10: If the dry bulb temperature is 85F and the wet bulb temperature is 70F, the dew point temperature will be approximately (use psychometric chart)
58F
70F
77F
32F
11: Absolute pressure is
Gauge Pressure
Atmospheric Pressure
Gauge + Atmospheric Pressure + Pi
none of the above
12: Refrigerant restricted in 2004 but used for transition for decades:
R-123
R-22
R-11
R-134A
13: Joints in piping for refrigeration containing parts must withstand temperatures of ___?
800F
1000F
600F
700F
14: How would you know if there was a loss of crankcase pressure?
oil will thicken
oil level will rise
oil will foam
oil will thin out
15: What is the minimum height refrigeration piping should be placed against walls?
7.25'
Ceiling height
72"
6'
16: A chilled water pump suction gauge reads 10 psig. Discharge gauge reads 48 psig. The head in feet of the pump is working against
108
88
38
116
17: If your suction line is warmer than the room temperature, this may indicate
plugged air filter
a low charge
below normal superheat
an over charge
18: Name three things that must be done when changing refrigeration lubricant?
Nothing must be done
You can't change lubricants.
Place sign, check for leaks, insulate
Make sure it's compatible, notify owner, notify AHJ
19: A single pole-double throw switch uses how many wires?(excluding the ground)
4
5
3
2
20: R-11 belongs to Group
B-3
A-1
B-1
A-2
21: Systems containing more than 110 pounds must have stop valves located at the
compressor suction inlet
compressor discharge outlet
receiver inlet and outlet
All of the above
22: Emergency shutdown procedures, including precautions to be observed in case of a breakdown or leak over 55 lbs of refrigerant charge, shall be displayed on a conspicuous card located as near as possible to the
boiler
outside the machinery room
compressor
evaporator
23: 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.
24: 14.7 psia is equivalent to
atmospheric pressure at seal level
29.92" Hg
0 psig
All of the above.
25: What must be done if refrigeration lines pass through a concrete floor?