HVAC 121 EXAMS 150 QUESTIONS & CORRECT
ANSWERS LATEST 2026
1. What is the maximum amount of refrigerant that a recovery cylinder should
contain?
A. 100% water capacity by weight.
B. 90% water capacity by weight.
C. 70% water capacity by weight.
D. 80% water capacity by weight.
D. 80% water capacity by weight.
2. During push-pull liquid recovery, vapor refrigerant is pulled from the
A. low side
B. recovery cylinder
C. high side
D. compressor
B. recovery cylinder
3. If the entire refrigerant charge has leaked out of a system, then a(n) —-should be
used to pressurize the system to test for leaks.
A. oxyacetylene mixture
B. butane solution
C. inert gas
D. soap-water solution
C. inert gas
4. Which evacuation method involves charging a system with nitrogen to absorb
moisture?
A. Passive evacuation.
B. Vapor evacuation.
C. Deep evacuation.
D. Triple evacuation.
,D. Triple evacuation.
5. When charging a system with refrigerant, the technician should put the low- and
high-side service valves in
A. back-seated position
B. front-seated position
C. mid-position
D. any position
C. mid-position
6. What is the superheat of a system if the refrigerant temperature in the suction
line is 58°F, its pressure in the evaporator is 60 psig, and its temperature in the
evaporator is 34°F?
A. 24°F.
B. 26°F.
C. 28°F.
D. 32°F.
A. 24°F.
7. To determine a system's subcooling value, the liquid line temperature should be
subtracted from the
temperature.
A. evaporator
B. compressor
C. suction line
D. condenser
D. condenser
8. Many recovery cylinders use a
A. filter-drier
B. liquid level switch
C. low-side float
D. pressure relief valve
B. liquid level switch
9. Calculate the tare weight of a cylinder if its total weight is 590 lb and the weight
of refrigerant in the cylinder is 450 lb. as a safety device to turn off the recovery
machine when the cylinder is
, A. 140 lb
B. 1,040 lb
C. 450 lb
D. 590 lb
A. 140 lb
10. Subcooling refers to the amount of —-removed from a refrigerant after it has
condensed.
A. latent heat
B. sensible heat
C. pressure
D. volume
B. sensible heat
11. Pressure that is greater than atmospheric pressure is referred to as — pressure.
A. positive
B. negative
C. vacuum
D. high-side
A. positive
12. Two-part epoxy resin kits usually include one tube filled with epoxy and
another tube filled with a(n) ______.
A. hardener
B. glue
C. burner fuel
D. acid solution
A. hardener
13. Low atmospheric humidity is indicated by an increase in the amount of
noticeable energy.
A. magnetic
B. kinetic
C. chemical
D. electrostatic
D. electrostatic
ANSWERS LATEST 2026
1. What is the maximum amount of refrigerant that a recovery cylinder should
contain?
A. 100% water capacity by weight.
B. 90% water capacity by weight.
C. 70% water capacity by weight.
D. 80% water capacity by weight.
D. 80% water capacity by weight.
2. During push-pull liquid recovery, vapor refrigerant is pulled from the
A. low side
B. recovery cylinder
C. high side
D. compressor
B. recovery cylinder
3. If the entire refrigerant charge has leaked out of a system, then a(n) —-should be
used to pressurize the system to test for leaks.
A. oxyacetylene mixture
B. butane solution
C. inert gas
D. soap-water solution
C. inert gas
4. Which evacuation method involves charging a system with nitrogen to absorb
moisture?
A. Passive evacuation.
B. Vapor evacuation.
C. Deep evacuation.
D. Triple evacuation.
,D. Triple evacuation.
5. When charging a system with refrigerant, the technician should put the low- and
high-side service valves in
A. back-seated position
B. front-seated position
C. mid-position
D. any position
C. mid-position
6. What is the superheat of a system if the refrigerant temperature in the suction
line is 58°F, its pressure in the evaporator is 60 psig, and its temperature in the
evaporator is 34°F?
A. 24°F.
B. 26°F.
C. 28°F.
D. 32°F.
A. 24°F.
7. To determine a system's subcooling value, the liquid line temperature should be
subtracted from the
temperature.
A. evaporator
B. compressor
C. suction line
D. condenser
D. condenser
8. Many recovery cylinders use a
A. filter-drier
B. liquid level switch
C. low-side float
D. pressure relief valve
B. liquid level switch
9. Calculate the tare weight of a cylinder if its total weight is 590 lb and the weight
of refrigerant in the cylinder is 450 lb. as a safety device to turn off the recovery
machine when the cylinder is
, A. 140 lb
B. 1,040 lb
C. 450 lb
D. 590 lb
A. 140 lb
10. Subcooling refers to the amount of —-removed from a refrigerant after it has
condensed.
A. latent heat
B. sensible heat
C. pressure
D. volume
B. sensible heat
11. Pressure that is greater than atmospheric pressure is referred to as — pressure.
A. positive
B. negative
C. vacuum
D. high-side
A. positive
12. Two-part epoxy resin kits usually include one tube filled with epoxy and
another tube filled with a(n) ______.
A. hardener
B. glue
C. burner fuel
D. acid solution
A. hardener
13. Low atmospheric humidity is indicated by an increase in the amount of
noticeable energy.
A. magnetic
B. kinetic
C. chemical
D. electrostatic
D. electrostatic
