Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: Megaohm meters can detect a ground in the
up to 1,000,000 ohms
10,000,000 ohms or higher
up to 1,000 ohms
up to 10,000 ohms
2: 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.
3.0, 3.5
2.5, 2.5
2.5, 3.0
6.6, 6.6
3: How many opening forces operate a thermostatic expansion valve?
3
1
4
2
4: R-123 belongs to Group
B-1
B-2
A-3
B-3
5: Group A3 refrigerants have a ______ flammability rating than Group B1 refrigerants
higher
the same
there is no Group B1 refrigerants
lower
6: 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
7: "E" references ____ in the Ohm's law formula
resistance
amperage
voltage
capacitance
8: Which refrigerant(s) is an HFC?
R-22
R-410A
R-502
All of the above
9: Liquid refrigerant flashing, or turning to vapor, in the liquid line may be due to
liquid line that is too small
shortage of refrigerant
liquid line that had too high vertical lift
All of the above
10: Capacity control on an absorption system is typically accomplished by varying the
speed of the chilled water circulatory pump
pressure setting on the system's rupture disc
speed of the condenser water circulator pump
rate at which heat is supplied to the generator
11: Which refrigerant was still able to be vented to the atmosphere after July 1, 1992?
R-22
R-12
R-11
R-113
12: A person holding a license as a refrigeration technician may connect or disconnect for the purpose of installation, repair, or replacement, any electrical device or control to be a part of a refrigeration or air conditioning system, from the
24 volt secondary side of the Class 2 transformer to the thermostat
first disconnect in
breaker panel in
load-side of the contactor in
13: Which refrigerant class listed below is the most flammable?
C3
B2
A2
A3
14: On an air cooled condenser, if the ambient air is 35F and dropping, what's its effect to the condensor?
it would have no effect on the condenser
it would make the condenser less efficient
it would cause the condenser to sweat
it would make the condenser more efficient
15: System design pressures must take into consideration, not only, pressures found during normal operation but also what?
When it's cold out
When there is a malfunction on the high side
When its warm out
All of the above
16: 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
17: The solution that leaves the concentrator in an absorption chiller is referred to as the
strong solution
absorbed solution
weak solution
diluted solution
18: If the spring is adjusted to increase the superheat, this new setting will
lengthen the frost line
shorten the frost line
have no effect on the frost line
allow more liquid into the evaporator
19: On a single phase motor, when does the start winding cut out?
25% of its RLA speed
100% of its RLA speed
75% of its RLA speed
50% of its RLA speed
20: What kind of material can't be used on the outlet of a relief valve?
PVC
Stainless Steel
Copper
Aluminum
21: When an electronic bridge is in balance the bridge output will be
0 volts
1 volt
.01 volts
15 volts
22: What device measures the specific gravity of a substance?
Thermometer
Hygrometer
Hydrometer
Manometer
23: In an air conditioning system, the unit of total heat energy content in an air/vapor mixture is
Enthalpy
Specific heat
Latent heat
Sensible heat
24: Instead of using a compressor, an absorption air-conditioning chiller uses which of the following as its driving force?
Oil
Air
Heat
Electricity
25: 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