North Carolina Refrigeration Contractor
Licensing Exam Questions And Correct
Answers (Verified Answers) Plus Rationales
2026 Q&A | Instant Download Pdf
1. When charging a refrigeration system, which gauge is primarily
used to monitor high-side pressure?
A. Low-pressure compound gauge
B. High-pressure gauge
C. Vacuum gauge
D. Micron gauge
High-side pressure is measured using the high-pressure gauge.
2. Which refrigerant classification indicates lower toxicity and no
flame propagation?
A. A3
B. B2
C. A1
D. B3
“A” = low toxicity; “1” = no flame propagation.
3. Superheat is measured at which location?
A. Compressor inlet
B. Condenser outlet
C. Evaporator outlet
D. Expansion device inlet
Superheat is evaluated at the evaporator outlet to ensure proper
refrigerant boiling.
,4. What type of compressor is most common in small commercial
refrigeration units?
A. Screw
B. Centrifugal
C. Reciprocating
D. Scroll
Reciprocating compressors are widely used in small/medium
refrigeration.
5. Which component meters refrigerant into the evaporator?
A. Compressor
B. Condenser
C. Receiver
D. Expansion device
Expansion devices control refrigerant flow and pressure drop.
6. Which tool is required for deep system evacuation?
A. Manifold set only
B. Two-stage vacuum pump
C. Recovery machine
D. Leak detector
Two-stage pumps reach lower microns for proper dehydration.
7. What is the primary purpose of the condenser?
A. Absorb heat
B. Create subcooling only
C. Reject heat
D. Increase superheat
Condensers remove heat from refrigerant.
, 8. A system showing high superheat and low suction pressure most
likely has:
A. Overcharge
B. Undercharge
C. Non-condensables
D. Restricted condenser airflow
Low refrigerant charge reduces evaporator feed and suction
pressure.
9. What color is the low-pressure side hose?
A. Red
B. Green
C. Blue
D. Yellow
Blue = low side; red = high.
10. What conditions indicate a condenser coil that is dirty?
A. Low head pressure
B. High head pressure
C. High superheat
D. Low superheat
Restricted airflow raises condensing pressure.
11. Which refrigerant is a natural refrigerant?
A. R-410A
B. R-404A
C. R-290
D. R-134a
R-290 (propane) is a hydrocarbon natural refrigerant.
Licensing Exam Questions And Correct
Answers (Verified Answers) Plus Rationales
2026 Q&A | Instant Download Pdf
1. When charging a refrigeration system, which gauge is primarily
used to monitor high-side pressure?
A. Low-pressure compound gauge
B. High-pressure gauge
C. Vacuum gauge
D. Micron gauge
High-side pressure is measured using the high-pressure gauge.
2. Which refrigerant classification indicates lower toxicity and no
flame propagation?
A. A3
B. B2
C. A1
D. B3
“A” = low toxicity; “1” = no flame propagation.
3. Superheat is measured at which location?
A. Compressor inlet
B. Condenser outlet
C. Evaporator outlet
D. Expansion device inlet
Superheat is evaluated at the evaporator outlet to ensure proper
refrigerant boiling.
,4. What type of compressor is most common in small commercial
refrigeration units?
A. Screw
B. Centrifugal
C. Reciprocating
D. Scroll
Reciprocating compressors are widely used in small/medium
refrigeration.
5. Which component meters refrigerant into the evaporator?
A. Compressor
B. Condenser
C. Receiver
D. Expansion device
Expansion devices control refrigerant flow and pressure drop.
6. Which tool is required for deep system evacuation?
A. Manifold set only
B. Two-stage vacuum pump
C. Recovery machine
D. Leak detector
Two-stage pumps reach lower microns for proper dehydration.
7. What is the primary purpose of the condenser?
A. Absorb heat
B. Create subcooling only
C. Reject heat
D. Increase superheat
Condensers remove heat from refrigerant.
, 8. A system showing high superheat and low suction pressure most
likely has:
A. Overcharge
B. Undercharge
C. Non-condensables
D. Restricted condenser airflow
Low refrigerant charge reduces evaporator feed and suction
pressure.
9. What color is the low-pressure side hose?
A. Red
B. Green
C. Blue
D. Yellow
Blue = low side; red = high.
10. What conditions indicate a condenser coil that is dirty?
A. Low head pressure
B. High head pressure
C. High superheat
D. Low superheat
Restricted airflow raises condensing pressure.
11. Which refrigerant is a natural refrigerant?
A. R-410A
B. R-404A
C. R-290
D. R-134a
R-290 (propane) is a hydrocarbon natural refrigerant.
