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Arizona CR-39 Air Conditioning, Refrigeration & Heating EXAM
QUESTIONS AND CORRECT VERIFIED SOLUTIONS LATEST
UPDATE THIS YEAR – JUST RELEASED
Arizona CR-39 Air Conditioning, Refrigeration & Heating Exam
10-Line Exam Coverage in Points Form
1. Licensing & Regulations – Arizona ROC jurisdiction, CR-39 (Dual) scope vs C-39
(Commercial) vs R-39 (Residential) , 4 years verifiable experience required within past 10
years , 70% passing score required , 80 questions, 210-minute time limit , semi-open
book with ICC codes permitted , EPA 608 Universal certification required for refrigerant
handling , surety bond requirements ($4,250–$50,000 based on volume) , Statutes &
Rules Exam (SRE) required , and disciplinary actions for working outside classification .
2. Refrigeration Systems – Vapor-compression cycle fundamentals (compression,
condensation, expansion, evaporation) , R-410A operating pressures (high side 200-300
psi, low side ~120 psi at 75°F) , R-22 phase-out (ODP >0, GWP 1760) , R-410A (ODP 0,
GWP 2088) , TXV function (regulates refrigerant flow into evaporator) , subcooling (8-
12°F typical TXV range) , superheat measurement , accumulator function (prevents liquid
slugging) , pressure switches (compressor overload protection) , and refrigerant recovery
systems .
3. Heating Systems – Dry systems: gas-fired furnaces and space heaters ; Wet systems:
steam (max 15 PSIG) and hot water (max 30 PSIG, 220°F) boilers and coils ; Category III
vent requirements (stainless steel for high-temp exhaust) ; sealed-combustion furnaces
(dedicated outside air intake) ; AFUE ratings (furnace heating efficiency) ; 2-stage furnace
operation (low stage: 40-60% capacity) ; cracked heat exchanger (carbon monoxide risk)
; combustion air requirements (IMC) ; and low-water cut-off switch function .
4. Controls & Motors – Thermostats (temperature control) ; pressure switches (compressor
protection) ; contactors (compressor motor start/stop) ; VFDs (variable-frequency drives
control motor speed via frequency adjustment) ; Ohm's Law (V = I × R) ; electrical
troubleshooting (short-to-ground in compressor windings) ; and control circuit wiring
fundamentals .
5. Ventilation & Duct Systems – Supply/return duct sizing (static pressure target ~0.2 in wg
per Manual D) ; total static pressure limit ≤0.5 in wg for residential systems ; vane
anemometer airflow measurement (CFM = velocity × area) ; turning vanes ; commercial
kitchen hoods (NFPA 96 capture velocity ≥150 ft/min) ; combustion air for gas
equipment ; and IAQ considerations .
6. Heat Pump Systems – Reversing valve function (changes refrigerant flow direction) ;
heating mode: outdoor coil acts as condenser ; cooling mode: outdoor coil acts as
evaporator ; supplemental/emergency heat ; defrost cycle ; and performance
comparison to furnaces .
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7. Installation & Safety – Minimum clearance (rooftop condensers to combustible roof: 12
inches per IMC) ; lockout/tagout procedure (first step: apply lockout device to electrical
disconnect) ; CSST gas piping protection (mechanical damage prevention and bonding) ;
brazing refrigerant lines (purge with nitrogen to prevent oxidation) ; deep vacuum (500
microns sufficient for R-22/R-410A) ; OSHA 29 CFR Part 1926 (safety standards) ; and
confined space entry protocols .
8. Codes & Reference Standards – International Mechanical Code (IMC) ; International Fuel
Gas Code (IFGC) ; SMACNA HVAC Systems: Testing, Adjusting and Balancing ; ACCA
Manual D (duct design) ; ACCA Manual J (residential load calculations) ; ACCA Manual S
(equipment selection) ; NFPA 96 (kitchen hoods) ; and OSHA 29 CFR Part 1926 .
9. Fluid Piping Systems – Fuel gas piping (IMC/IFGC requirements) ; CSST bonding and
protection ; water piping from service connection to equipment ; steam, hot, chilled,
and condensing water systems ; pressure-reducing valves (PRV) ; expansion tank
purpose (accommodates volume changes due to temperature fluctuations) ; suction line
slope (1/4" per foot toward compressor for oil return) ; and maximum suction velocity
for R-410A (250-300 ft/min) .
10. Testing, Balancing & Estimating – Air balancing with balometer ; static pressure
measurement ; duct leakage testing ; system commissioning ; load calculations for
equipment sizing ; Manual J (residential) ; Manual D (duct design) ; SEER ratings (cooling
efficiency) ; and material take-off .
250 MCQ Questions with Rationales
Question 1
According to the International Mechanical Code adopted in Arizona, what is the minimum
clearance required between a rooftop condenser and a combustible roof surface?
A) 6 inches
B) 12 inches
C) 18 inches
D) 24 inches
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Correct Answer: B
Rationale: The IMC requires at least 12 inches clearance between a rooftop condenser and
combustible surfaces to reduce fire risk and allow adequate service access for maintenance and
airflow . This clearance also ensures proper condenser performance by preventing recirculation
of hot discharge air.
Question 2
In Arizona, which agency is responsible for licensing HVAC contractors?
A) Arizona Department of Environmental Quality
B) Arizona Registrar of Contractors (ROC)
C) Arizona Corporation Commission
D) Arizona Secretary of State
Correct Answer: B
Rationale: The Arizona Registrar of Contractors (ROC) is the governing board that licenses and
regulates all residential and commercial contractors, including HVAC contractors in the CR-39, C-
39, and R-39 classifications . The ROC administers the examination process and enforces
licensing requirements under Arizona Revised Statutes Title 32, Chapter 10.
Question 3
What is the minimum number of years of verifiable experience required for an Arizona HVAC
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contractor license?
A) 2 years
B) 3 years
C) 4 years
D) 5 years
Correct Answer: C
Rationale: Arizona requires a minimum of four years of verifiable experience in the specific
HVAC classification within the past ten years . Up to two years of this experience can be satisfied
through technical training or an apprenticeship program.
Question 4
What is the passing score required for the Arizona CR-39 HVAC contractor examination?
A) 60%
B) 65%
C) 70%
D) 75%
Correct Answer: C
Rationale: All Arizona contractor examinations require a minimum passing score of 70% . This
applies to both the trade-specific exam (80 questions) and the Statutes and Rules Exam (SRE),
with the CR-39 exam having a 210-minute time limit .
Arizona CR-39 Air Conditioning, Refrigeration & Heating EXAM
QUESTIONS AND CORRECT VERIFIED SOLUTIONS LATEST
UPDATE THIS YEAR – JUST RELEASED
Arizona CR-39 Air Conditioning, Refrigeration & Heating Exam
10-Line Exam Coverage in Points Form
1. Licensing & Regulations – Arizona ROC jurisdiction, CR-39 (Dual) scope vs C-39
(Commercial) vs R-39 (Residential) , 4 years verifiable experience required within past 10
years , 70% passing score required , 80 questions, 210-minute time limit , semi-open
book with ICC codes permitted , EPA 608 Universal certification required for refrigerant
handling , surety bond requirements ($4,250–$50,000 based on volume) , Statutes &
Rules Exam (SRE) required , and disciplinary actions for working outside classification .
2. Refrigeration Systems – Vapor-compression cycle fundamentals (compression,
condensation, expansion, evaporation) , R-410A operating pressures (high side 200-300
psi, low side ~120 psi at 75°F) , R-22 phase-out (ODP >0, GWP 1760) , R-410A (ODP 0,
GWP 2088) , TXV function (regulates refrigerant flow into evaporator) , subcooling (8-
12°F typical TXV range) , superheat measurement , accumulator function (prevents liquid
slugging) , pressure switches (compressor overload protection) , and refrigerant recovery
systems .
3. Heating Systems – Dry systems: gas-fired furnaces and space heaters ; Wet systems:
steam (max 15 PSIG) and hot water (max 30 PSIG, 220°F) boilers and coils ; Category III
vent requirements (stainless steel for high-temp exhaust) ; sealed-combustion furnaces
(dedicated outside air intake) ; AFUE ratings (furnace heating efficiency) ; 2-stage furnace
operation (low stage: 40-60% capacity) ; cracked heat exchanger (carbon monoxide risk)
; combustion air requirements (IMC) ; and low-water cut-off switch function .
4. Controls & Motors – Thermostats (temperature control) ; pressure switches (compressor
protection) ; contactors (compressor motor start/stop) ; VFDs (variable-frequency drives
control motor speed via frequency adjustment) ; Ohm's Law (V = I × R) ; electrical
troubleshooting (short-to-ground in compressor windings) ; and control circuit wiring
fundamentals .
5. Ventilation & Duct Systems – Supply/return duct sizing (static pressure target ~0.2 in wg
per Manual D) ; total static pressure limit ≤0.5 in wg for residential systems ; vane
anemometer airflow measurement (CFM = velocity × area) ; turning vanes ; commercial
kitchen hoods (NFPA 96 capture velocity ≥150 ft/min) ; combustion air for gas
equipment ; and IAQ considerations .
6. Heat Pump Systems – Reversing valve function (changes refrigerant flow direction) ;
heating mode: outdoor coil acts as condenser ; cooling mode: outdoor coil acts as
evaporator ; supplemental/emergency heat ; defrost cycle ; and performance
comparison to furnaces .
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7. Installation & Safety – Minimum clearance (rooftop condensers to combustible roof: 12
inches per IMC) ; lockout/tagout procedure (first step: apply lockout device to electrical
disconnect) ; CSST gas piping protection (mechanical damage prevention and bonding) ;
brazing refrigerant lines (purge with nitrogen to prevent oxidation) ; deep vacuum (500
microns sufficient for R-22/R-410A) ; OSHA 29 CFR Part 1926 (safety standards) ; and
confined space entry protocols .
8. Codes & Reference Standards – International Mechanical Code (IMC) ; International Fuel
Gas Code (IFGC) ; SMACNA HVAC Systems: Testing, Adjusting and Balancing ; ACCA
Manual D (duct design) ; ACCA Manual J (residential load calculations) ; ACCA Manual S
(equipment selection) ; NFPA 96 (kitchen hoods) ; and OSHA 29 CFR Part 1926 .
9. Fluid Piping Systems – Fuel gas piping (IMC/IFGC requirements) ; CSST bonding and
protection ; water piping from service connection to equipment ; steam, hot, chilled,
and condensing water systems ; pressure-reducing valves (PRV) ; expansion tank
purpose (accommodates volume changes due to temperature fluctuations) ; suction line
slope (1/4" per foot toward compressor for oil return) ; and maximum suction velocity
for R-410A (250-300 ft/min) .
10. Testing, Balancing & Estimating – Air balancing with balometer ; static pressure
measurement ; duct leakage testing ; system commissioning ; load calculations for
equipment sizing ; Manual J (residential) ; Manual D (duct design) ; SEER ratings (cooling
efficiency) ; and material take-off .
250 MCQ Questions with Rationales
Question 1
According to the International Mechanical Code adopted in Arizona, what is the minimum
clearance required between a rooftop condenser and a combustible roof surface?
A) 6 inches
B) 12 inches
C) 18 inches
D) 24 inches
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Correct Answer: B
Rationale: The IMC requires at least 12 inches clearance between a rooftop condenser and
combustible surfaces to reduce fire risk and allow adequate service access for maintenance and
airflow . This clearance also ensures proper condenser performance by preventing recirculation
of hot discharge air.
Question 2
In Arizona, which agency is responsible for licensing HVAC contractors?
A) Arizona Department of Environmental Quality
B) Arizona Registrar of Contractors (ROC)
C) Arizona Corporation Commission
D) Arizona Secretary of State
Correct Answer: B
Rationale: The Arizona Registrar of Contractors (ROC) is the governing board that licenses and
regulates all residential and commercial contractors, including HVAC contractors in the CR-39, C-
39, and R-39 classifications . The ROC administers the examination process and enforces
licensing requirements under Arizona Revised Statutes Title 32, Chapter 10.
Question 3
What is the minimum number of years of verifiable experience required for an Arizona HVAC
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contractor license?
A) 2 years
B) 3 years
C) 4 years
D) 5 years
Correct Answer: C
Rationale: Arizona requires a minimum of four years of verifiable experience in the specific
HVAC classification within the past ten years . Up to two years of this experience can be satisfied
through technical training or an apprenticeship program.
Question 4
What is the passing score required for the Arizona CR-39 HVAC contractor examination?
A) 60%
B) 65%
C) 70%
D) 75%
Correct Answer: C
Rationale: All Arizona contractor examinations require a minimum passing score of 70% . This
applies to both the trade-specific exam (80 questions) and the Statutes and Rules Exam (SRE),
with the CR-39 exam having a 210-minute time limit .
