AZ C-39 Air Conditioning Contractor
Exam Questions And Correct Answers
(Verified Answers) Plus Rationale2026
Q&A| Instant Download Pdf
1. What is the primary purpose of a refrigerant in an air conditioning
system?
A. To generate heat
B. To absorb and remove heat
C. To circulate air
D. To filter contaminants
B. To absorb and remove heat
Rationale: Refrigerants absorb heat from indoor air and release it
outside, enabling cooling.
2. Which of the following is a common type of refrigerant used in
residential air conditioning?
A. R-12
B. R-22
C. R-410A
D. All of the above
D. All of the above
Rationale: R-12 is mostly phased out, R-22 is being replaced, and R-
410A is common in new systems.
3. What does SEER stand for in air conditioning systems?
A. Seasonal Energy Efficiency Ratio
B. Standard Energy Emission Rate
C. System Efficiency Evaluation Rating
D. Seasonal Electrical Energy Ratio
A. Seasonal Energy Efficiency Ratio
, Rationale: SEER measures the cooling output per unit of electricity
over a typical cooling season.
4. Which component compresses refrigerant in a central air conditioning
system?
A. Evaporator
B. Condenser
C. Compressor
D. Expansion valve
C. Compressor
Rationale: The compressor pressurizes the refrigerant, causing it to
circulate through the system.
5. What is the main function of the evaporator coil?
A. Release heat outside
B. Absorb heat from indoor air
C. Increase refrigerant pressure
D. Filter indoor air
B. Absorb heat from indoor air
Rationale: The evaporator coil allows the refrigerant to absorb heat,
cooling the indoor air.
6. Which of the following is an example of a split system air conditioner?
A. Window unit
B. Packaged unit
C. Central air with indoor and outdoor components
D. Portable AC
C. Central air with indoor and outdoor components
Rationale: Split systems have separate indoor evaporators and
outdoor condensers.
7. Which type of airflow is typically recommended for residential duct
design?
A. 400–600 CFM per ton of cooling
B. 800–1000 CFM per ton of cooling
C. 200–300 CFM per ton of cooling
D. 1000–1200 CFM per ton of cooling
A. 400–600 CFM per ton of cooling
Rationale: This airflow range ensures efficient heat transfer and
system performance.
, 8. What is the purpose of a TXV (thermostatic expansion valve)?
A. To compress refrigerant
B. To meter refrigerant into the evaporator
C. To remove moisture from the air
D. To filter indoor air
B. To meter refrigerant into the evaporator
Rationale: TXVs control refrigerant flow based on the evaporator
load.
9. Which type of refrigerant is considered ozone-friendly?
A. R-22
B. R-410A
C. R-12
D. R-502
B. R-410A
Rationale: R-410A does not deplete the ozone layer unlike R-22 and
R-12.
10. What safety device prevents excessive pressure in an air
conditioning system?
A. Thermostat
B. Pressure relief valve
C. Expansion valve
D. Check valve
B. Pressure relief valve
Rationale: This device protects the system from overpressure
conditions that could cause damage or rupture.
11. What is the recommended refrigerant charge method for most
modern AC systems?
A. By weight
B. By sight glass
C. By pressure gauge alone
D. By guess
A. By weight
Rationale: Charging by weight ensures the correct refrigerant
amount according to manufacturer specifications.
12. Which tool is essential for diagnosing refrigerant leaks?
A. Multimeter
B. Leak detector
Exam Questions And Correct Answers
(Verified Answers) Plus Rationale2026
Q&A| Instant Download Pdf
1. What is the primary purpose of a refrigerant in an air conditioning
system?
A. To generate heat
B. To absorb and remove heat
C. To circulate air
D. To filter contaminants
B. To absorb and remove heat
Rationale: Refrigerants absorb heat from indoor air and release it
outside, enabling cooling.
2. Which of the following is a common type of refrigerant used in
residential air conditioning?
A. R-12
B. R-22
C. R-410A
D. All of the above
D. All of the above
Rationale: R-12 is mostly phased out, R-22 is being replaced, and R-
410A is common in new systems.
3. What does SEER stand for in air conditioning systems?
A. Seasonal Energy Efficiency Ratio
B. Standard Energy Emission Rate
C. System Efficiency Evaluation Rating
D. Seasonal Electrical Energy Ratio
A. Seasonal Energy Efficiency Ratio
, Rationale: SEER measures the cooling output per unit of electricity
over a typical cooling season.
4. Which component compresses refrigerant in a central air conditioning
system?
A. Evaporator
B. Condenser
C. Compressor
D. Expansion valve
C. Compressor
Rationale: The compressor pressurizes the refrigerant, causing it to
circulate through the system.
5. What is the main function of the evaporator coil?
A. Release heat outside
B. Absorb heat from indoor air
C. Increase refrigerant pressure
D. Filter indoor air
B. Absorb heat from indoor air
Rationale: The evaporator coil allows the refrigerant to absorb heat,
cooling the indoor air.
6. Which of the following is an example of a split system air conditioner?
A. Window unit
B. Packaged unit
C. Central air with indoor and outdoor components
D. Portable AC
C. Central air with indoor and outdoor components
Rationale: Split systems have separate indoor evaporators and
outdoor condensers.
7. Which type of airflow is typically recommended for residential duct
design?
A. 400–600 CFM per ton of cooling
B. 800–1000 CFM per ton of cooling
C. 200–300 CFM per ton of cooling
D. 1000–1200 CFM per ton of cooling
A. 400–600 CFM per ton of cooling
Rationale: This airflow range ensures efficient heat transfer and
system performance.
, 8. What is the purpose of a TXV (thermostatic expansion valve)?
A. To compress refrigerant
B. To meter refrigerant into the evaporator
C. To remove moisture from the air
D. To filter indoor air
B. To meter refrigerant into the evaporator
Rationale: TXVs control refrigerant flow based on the evaporator
load.
9. Which type of refrigerant is considered ozone-friendly?
A. R-22
B. R-410A
C. R-12
D. R-502
B. R-410A
Rationale: R-410A does not deplete the ozone layer unlike R-22 and
R-12.
10. What safety device prevents excessive pressure in an air
conditioning system?
A. Thermostat
B. Pressure relief valve
C. Expansion valve
D. Check valve
B. Pressure relief valve
Rationale: This device protects the system from overpressure
conditions that could cause damage or rupture.
11. What is the recommended refrigerant charge method for most
modern AC systems?
A. By weight
B. By sight glass
C. By pressure gauge alone
D. By guess
A. By weight
Rationale: Charging by weight ensures the correct refrigerant
amount according to manufacturer specifications.
12. Which tool is essential for diagnosing refrigerant leaks?
A. Multimeter
B. Leak detector
