- Eligibility Basics for the AZ-ACR Trade Exam
- Experience Requirements: Four Years, Two Recent
- Choosing the R-39R/C-39 Classification
- Registration and Fee Mechanics
- Exam Format Requirements You Must Meet
- Domain Coverage You're Required to Master
- Approved References and Open-Book Rules
- Retake Waiting Periods
- Results Validity and License Application Timing
- A Domain-Ordered Prep Schedule
- Frequently Asked Questions
- Qualifying parties typically need four years of trade experience, with two years inside the last decade.
- Qualifying technical training can substitute for up to two of the four required experience years.
- The trade exam is 80 questions, 210 minutes, and requires a 70% score to pass.
- You must also pass the separate $61 Arizona Statutes and Rules Exam (SRE) in addition to the $66 trade exam.
Eligibility Basics for the AZ-ACR Trade Exam
Before you can sit for the R-39R/C-39 (CR-39) Air Conditioning and Refrigeration exam through PSI on behalf of the Arizona Registrar of Contractors, you need to understand who the exam is actually built for. This is not a generic HVAC knowledge quiz - it's a licensing requirement tied to a specific contractor classification that covers residential and commercial air conditioning and refrigeration work under Arizona Revised Statutes section 32-1122 and section 32-1123.01.
The exam candidate is usually the qualifying party for a contracting business - the individual whose experience and passing score allow the company to hold an active CR-39 license. If you're unclear on what the credential actually represents before diving into eligibility rules, the overview at What Is AZ-ACR? and the plain-language breakdown in AZ-ACR Meaning are useful starting points.
Experience Requirements: Four Years, Two Recent
The core eligibility rule is experience-based rather than education-based. A qualifying party ordinarily needs four years of practical or management trade experience, and at least two of those years must fall within the preceding ten years. This keeps the license tied to someone with reasonably current field involvement, not just decades-old work history.
There is one meaningful flexibility built into the rule: qualifying technical training can substitute for up to two years of the four-year requirement. That means a candidate with strong formal HVAC/R coursework, apprenticeship credentials, or documented technical training may be able to shorten the hands-on clock, provided the remaining experience and recency requirements are still satisfied.
Key Takeaway
If you're light on raw years, don't assume you're disqualified - document your technical training carefully, since it can offset up to two of the four required experience years.
Choosing the R-39R/C-39 Classification
One of the most commercially important - and most overlooked - steps in the process is confirming you're preparing for the correct classification. This article, and the exam it covers, is specifically the non-solar R-39R/C-39 (CR-39) residential/commercial air conditioning and refrigeration trade examination. Arizona's contractor licensing structure includes multiple trade classifications, and picking the wrong one wastes both exam fees and preparation time.
Before scheduling, verify with the ROC and PSI that CR-39 matches the scope of work your business intends to perform - residential and commercial air conditioning and refrigeration systems, as opposed to solar-specific or purely mechanical classifications. If you want a deeper explanation of how this credential is structured and what it authorizes, see AZ-ACR Certification and What Is AZ-ACR Certification?.
Why Exact Classification Matters
PSI administers many similarly-named trade outlines for Arizona contractors. Confirming the R-39R/C-39 (CR-39) outline - dated June 8, 2023 - avoids studying content weighted for a different license type.
- Check the classification code on your exam registration confirmation before test day.
- Cross-reference the outline's 12 domains against what you studied.
Registration and Fee Mechanics
Two separate exams stand between a qualifying party and license eligibility:
- The CR-39 trade examination, administered by PSI Services LLC, costs $66 per attempt.
- The Arizona Statutes and Rules Exam (SRE), a separate online exam, costs $61.
These are exam fees only - license fees and bond obligations are handled separately through the ROC, and licenses renew on a biennial cycle once issued. If you're budgeting for the full path to licensure, the detailed cost breakdown at AZ-ACR Certification Cost 2026: Complete Pricing Breakdown walks through how the trade exam fee, SRE fee, and licensing costs stack up.
Testing is computer-based multiple choice, available through both test-center appointments and remote-proctored delivery. If you go remote, be aware that scratch paper and breaks are prohibited during remote sessions - a detail that surprises candidates who assume remote testing mirrors an in-center experience.
Exam Format Requirements You Must Meet
Format requirements matter as much as content knowledge when it comes to qualifying for a passing result. The CR-39 trade outline specifies:
- 80 scored questions, delivered as computer-based multiple choice.
- A 70% passing score requirement.
- A 210-minute time allotment.
- PSI may embed 5 to 10 unscored experimental questions within that same time window, meaning the visible question count on your screen can exceed 80 without extra time being added.
A silent, nonprinting, nonprogrammable, nonscientific calculator is permitted under the general PSI candidate bulletin. Since the exam mixes recall questions with original trade scenarios that require multi-step reasoning, pacing across 210 minutes is a real factor - not just knowledge recall. For a full breakdown of what "70%" actually means in raw question terms, see AZ-ACR Passing Score 2026: Exactly What You Need to Pass, and for a candid assessment of how demanding the format is, read How Hard Is the AZ-ACR Exam? Complete Difficulty Guide 2026.
Key Takeaway
Because experimental questions are unscored but indistinguishable from scored ones, don't burn excessive time second-guessing any single question - trust your pacing plan across all 210 minutes.
Domain Coverage You're Required to Master
Eligibility isn't just about experience years - it's also about proving competency across a defined content outline. The CR-39 exam allocates questions across 12 domains, and the distribution tells you exactly where to weight your preparation:
| Domain | Questions |
|---|---|
| 1. Refrigeration | 12 |
| 2. Air Conditioning | 12 |
| 3. Warm Air Heating | 12 |
| 4. Controls and Motors | 8 |
| 5. Boilers | 4 |
| 6. Ventilation | 4 |
| 7. Evaporative Coolers | 4 |
| 8. Fuel Piping Systems | 5 |
| 9. Water Piping Systems | 5 |
| 10. Steam, Hot, Chilled, and Condensing Water | 5 |
| 11. Testing, Balancing, and Inspections | 5 |
| 12. Sizing and Estimating | 4 |
Refrigeration, Air Conditioning, and Warm Air Heating are the joint-largest subject areas, each carrying 12 questions - together they represent well over a third of the entire exam. Candidates who treat those three domains as equally weighted study priorities, rather than favoring one over the others, put themselves in a stronger position than those who lean heavily on refrigeration knowledge while neglecting warm-air heating equipment and controls.
For a domain-by-domain walkthrough of what each content area actually tests - including typical scenario types within Controls and Motors, Fuel Piping Systems, and Sizing and Estimating - see AZ-ACR Exam Domains 2026: Complete Guide to All 12 Content Areas.
Refrigeration, Air Conditioning, Warm Air Heating
These three domains carry the heaviest question weight and deserve proportionally more study hours than any other content area.
- Refrigerant cycle components, pressures, and troubleshooting logic
- Cooling load fundamentals and equipment matching
- Combustion, venting, and heat exchanger principles for warm-air systems
Controls and Motors
At 8 questions, this domain is the largest of the mid-tier content areas and blends electrical theory with mechanical control logic.
- Motor types, starting methods, and protection devices
- Thermostats, relays, and safety control sequencing
Approved References and Open-Book Rules
The CR-39 exam is partially open-book, but only specific references qualify, and the rules for marking them up are strict. Approved open-book references are:
- OSHA 29 CFR Part 1926, or PSI's selections with the latest available amendments
- The 2018 International Fuel Gas Code
- The 2018 International Mechanical Code
Any other textbook listed on the trade outline is a study-only reference - it will help you learn the material, but you cannot bring it into the exam. Advance highlighting, underlining, annotations, and permanent tabs in your approved references are allowed going into the test, but loose additional papers and writing in the references during the actual exam session are prohibited.
Retake Waiting Periods
If you don't pass on your first attempt, Arizona's retake rules require a waiting period before you can try again:
- A 30-day wait applies between most retake attempts.
- Starting with your fourth and any subsequent attempt, the waiting period extends to 90 days.
Each retake also requires paying the $66 trade exam fee again, so a failed attempt has both a time cost and a financial cost. This makes first-attempt preparation meaningfully more valuable than treating the exam as something you can simply retake quickly and cheaply. For a structured, first-attempt-focused approach, see AZ-ACR Study Guide 2026: How to Pass on Your First Attempt.
Results Validity and License Application Timing
Passing the exam is not the finish line - timing your license application matters too. Examination results must fall within the two years preceding the license application. If you pass the CR-39 exam but delay submitting your ROC license application beyond that window, your passing result can expire relative to the application, potentially forcing a retest.
Once licensed, contractor licenses renew on a biennial basis, with license fees and bond obligations tracked separately from the original exam fees. Plan your application timeline around this two-year validity window rather than assuming a passing score is permanently banked. If you're mapping out testing windows and deadlines around your business plans, AZ-ACR Exam Dates 2026: Testing Windows, Deadlines & Scheduling covers scheduling mechanics in more depth.
Key Takeaway
Don't pass the exam and then sit on your results - submit your ROC license application while your score is still within the two-year validity window.
A Domain-Ordered Prep Schedule
Generic study techniques only help if they're applied against the right content priorities. Given that Refrigeration, Air Conditioning, and Warm Air Heating jointly account for 36 of the 80 scored questions, a preparation schedule should front-load those domains while still covering every smaller domain before test day.
Refrigeration, Air Conditioning, Warm Air Heating
- Work through refrigerant cycle logic, cooling load basics, and combustion/heat exchanger fundamentals in parallel since they're equally weighted
- Practice original scenario-style questions rather than pure definition recall
Controls and Motors, plus Fuel and Water Piping Systems
- Cover motor protection devices and control sequencing
- Review fuel gas piping sizing alongside the 2018 IFGC you'll have open-book
Boilers, Ventilation, Evaporative Coolers, Steam/Hot/Chilled Water, Testing & Balancing, Sizing & Estimating
- Batch the smaller 4-5 question domains together for efficient review
- Run full-length timed practice sets to build 210-minute pacing endurance
Use the domain question counts as your allocation guide, not a generic weekly template - a domain worth 12 questions deserves roughly triple the review time of one worth 4. For additional practice material structured around this exact outline, the question bank at the AZ-ACR practice test platform mirrors the 12-domain breakdown so your practice sessions match real exam weighting.
Frequently Asked Questions
Qualifying parties ordinarily need four years of practical or management trade experience, with two of those years occurring within the preceding ten years. Qualifying technical training can substitute for up to two of the four years.
No. The SRE is a separate online exam costing $61, distinct from the $66 CR-39 trade examination. Both must typically be completed as part of the licensing path.
You must wait 30 days before retaking for most attempts. Starting with your fourth attempt and beyond, the required waiting period extends to 90 days, and the exam fee applies again each time.
Only the approved open-book references qualify: OSHA 29 CFR Part 1926 (or PSI's equivalent selections), the 2018 International Fuel Gas Code, and the 2018 International Mechanical Code. Other listed textbooks are for study purposes only and are not permitted in the exam.
Exam results must fall within the two years preceding your license application to the Arizona Registrar of Contractors, so timing your application matters after passing.
Understanding these eligibility mechanics - experience thresholds, correct classification selection, fee structure, format rules, and results timing - is the practical foundation for approaching the CR-39 exam with confidence. For a broader look at how this credential fits into career and business planning, see Is the AZ-ACR Certification Worth It? Complete ROI Analysis 2026 and AZ-ACR Jobs, and browse practice questions built around the official 12-domain outline to test your readiness before scheduling.