Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: One atmosphere equals
29.4
0 psig
0 psia
14.7
2: A mercury bulb controller is not recommended for
line voltage use
use where vibration is severe
line or low voltage use
low voltage use
3: A pressure vessel having an inside diameter of 6” or less shall be sufficient to withstand ____times the pressure of the saturation temperature of the refrigerant or ____times the critical pressure of the refrigerant, whichever is less.
6.6, 6.6
3.0, 3.5
2.5, 3.0
2.5, 2.5
4: What is the temperature that a liquid and a vapor can exist in equilibrium called?
Saturated temperature
Dry bulb temperature
Critical temperature
Wet bulb temperature
5: Defined process piping by code CMR (528)
Any piping that conveys a solid, liquid or gas that is not part of the plumbing or fire protection system
Any piping in an industrial space
Any piping in an industrial or commercial space
All of the above
6: What is the minimum size of the discharge pipe?
Same size as the outlet of the relief valve
One pipe size larger that the inlet of the relief valve
Depends on size of manifold
All of the above
7: Gauge pressure is
what a gauge reads when checking pressures on a chilled water system.
atmospheric pressure
absolute pressure
force of pressure above that of atmospheric
8: What is Absolute Zero?
-400F
-640F
-460F
-773F
9: What device measures the specific gravity of a substance?
Thermometer
Hydrometer
Manometer
Hygrometer
10: The gauge thickness required on a CO2 tank construction is
1/16"
1/8"
3/32"
5/16"
11: The most common type of motor starter is
delts-wye starter
across the line starter
duel-winding starter
part winding starter
12: In an electrical circuit, what is potential measured in?
Amps
Ohms
Volts
Herys
13: A normally operating R-410A system with a condensing temperature of 110F will have a high side pressure of around ______ psig
255 psig
365 psig
327 psig
125 psig
14: A factory-sealed system containing less than 22lbs. of Group A1 refrigerant
shall have a pressure limiting device installed on the high side of the system
shall be inspected by the Boiler of Inspectors bi-annually
does not require a pressure-limiting device
shall have a pressure limiting device and a pressure relief valve installed
15: A class B2 refrigerant is considered
non-toxic and non-flammable
toxic and somewhat flammable
non-toxic and highly flammable
toxic and non-flammable
16: What device should be used on low-temperature freezers?
hot-gas by-pass
high capacity TXV
discharge muffler
oil separator
17: Group A2 refrigerants have a ______ toxicity rating than Group B1 refrigerants.
lower
higher
there is no Group B1 refrigerants
the same
18: A 24 volt transformer with a 240 volt primary can handle how many amps?
There isn't enough information to answer.
20 amps
10 amps
24 amps
19: When a pressure gauge is permanently installed on a system, it must be ___ times the design pressure of the system.
1.5
2.2
1
1.2
20: 746 watts is equal to
10 hp
1 hp
100 hp
Pi
21: How do you find net oil pressure on a compressor?
discharge pressure - suction pressure
gross oil pressure - suction pressure
gross oil pressure - discharge pressure
all of the above
22: Liquid refrigerant R-22 enters an evaporator at 50.2 psig, 20F and leaves 37F, its pressure as it leaves will be
70.8 psig
50.2 psig
66.1 psig
43.3 psig
23: How many different groups of refrigerants are there?
15
11
3
7
24: How many opening forces operate a thermostatic expansion valve?
4
2
1
3
25: A premise or that portion of a premise where people transact business, receive personal service, or purchase foods, other goods is considered a