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LOW GWP REFRIGERANT –ACTUAL
PRACTICE QUESTIONS WITH ANSWERS
GRADE A+ 2026
When working with A2L refrigerants, which one of the following is not an
approved leak detection method?
Electronic leak detector.
Halide leak detector.
Microfoam solution (bubbles).
Ultrasonic leak detector. - correct-answer -Halide leak detector.
When brazing a system that has been charged with an A2L refrigerant:
NFPA 704 hazard placards must be placed in visible locations around the
perimeter of the jobsite.
The refrigerant tubing should be pressurized with air to stablize the inner walls.
The system charge must be vented to the atmosphere before beginning.
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The system should be swept with nitrogen to ensure that there is no residual
refrigerant. - correct-answer -The system should be swept with nitrogen to
ensure that there is no residual refrigerant.
Refrigerants that have a lowercase designation, such as R-134a, indicates a(n):
Azeotrope blend.
Isomer.
Olefin.
Zeotropic blend. - correct-answer -Isomer.
Which of the following is classified as an A2L refrigerant?
R-290
R-441A
R-744
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R-1234yf - correct-answer -R-1234yf
When using a flammable refrigerant as a trace gas for leak detection, the amount
must not exceed:
10% of the upper explosive limit (UEL) of the refrigerant..
25% of the lower flammability limit (LFL) of the refrigerant..
25% of the upper explosive limit (UEL) of the refrigerant.
35% of the lower flammability limit (LFL) of the refrigerant. - correct-answer -25%
of the lower flammability limit (LFL) of the refrigerant..
Hydrogen fluoride (HF) can form when:
Any chlorine-containing refrigerant undergoes complete or incomplete
combustion or thermal decomposition.
Any chlorine-containing refrigerant undergoes fractionation.
Any fluorine-containing refrigerant undergoes complete or incomplete
combustion or thermal decomposition.
LOW GWP REFRIGERANT –ACTUAL
PRACTICE QUESTIONS WITH ANSWERS
GRADE A+ 2026
When working with A2L refrigerants, which one of the following is not an
approved leak detection method?
Electronic leak detector.
Halide leak detector.
Microfoam solution (bubbles).
Ultrasonic leak detector. - correct-answer -Halide leak detector.
When brazing a system that has been charged with an A2L refrigerant:
NFPA 704 hazard placards must be placed in visible locations around the
perimeter of the jobsite.
The refrigerant tubing should be pressurized with air to stablize the inner walls.
The system charge must be vented to the atmosphere before beginning.
,2|Page
The system should be swept with nitrogen to ensure that there is no residual
refrigerant. - correct-answer -The system should be swept with nitrogen to
ensure that there is no residual refrigerant.
Refrigerants that have a lowercase designation, such as R-134a, indicates a(n):
Azeotrope blend.
Isomer.
Olefin.
Zeotropic blend. - correct-answer -Isomer.
Which of the following is classified as an A2L refrigerant?
R-290
R-441A
R-744
, 3|Page
R-1234yf - correct-answer -R-1234yf
When using a flammable refrigerant as a trace gas for leak detection, the amount
must not exceed:
10% of the upper explosive limit (UEL) of the refrigerant..
25% of the lower flammability limit (LFL) of the refrigerant..
25% of the upper explosive limit (UEL) of the refrigerant.
35% of the lower flammability limit (LFL) of the refrigerant. - correct-answer -25%
of the lower flammability limit (LFL) of the refrigerant..
Hydrogen fluoride (HF) can form when:
Any chlorine-containing refrigerant undergoes complete or incomplete
combustion or thermal decomposition.
Any chlorine-containing refrigerant undergoes fractionation.
Any fluorine-containing refrigerant undergoes complete or incomplete
combustion or thermal decomposition.
