- What Is AZ-ACR Certification, Exactly?
- Who Administers the Exam and Why It Matters
- Exam Format, Timing, and Fees
- The 12 Domains and Their Question Weights
- What You Can (and Can't) Bring Into the Test
- Who Qualifies to Sit for the Exam
- Retake Waiting Periods
- Who Actually Needs This Certification
- Building a Domain-Aware Study Plan
- After You Pass: License and Renewal
- Frequently Asked Questions
- AZ-ACR here refers specifically to the R-39R/C-39 (CR-39) trade exam issued through the Arizona Registrar of Contractors.
- The trade exam has 80 scored questions plus possible experimental items, a 210-minute limit, and a 70% pass requirement.
- Refrigeration, Air Conditioning, and Warm Air Heating each carry 12 questions - the heaviest domains on the outline.
- The trade exam costs $66 per attempt; the separate Statutes and Rules Exam (SRE) costs $61.
What Is AZ-ACR Certification, Exactly?
AZ-ACR, in the context of this site, refers to the Arizona R-39R/C-39 (CR-39) Air Conditioning and Refrigeration (Residential/Commercial) Examination - the trade competency exam administered through PSI Services LLC on behalf of the Arizona Registrar of Contractors (ROC). This is not a manufacturer certification or a national HVAC credentialing badge; it is the licensing exam a qualifying party must pass before a business can hold a residential/commercial air conditioning and refrigeration contractor's license in Arizona.
If you've landed here searching for "Arizona CR-39 practice test" or "Arizona C-39 exam," you're in the right place. The exam is built around a formal outline that specifies exactly how many questions come from each subject area, how long you get, and what score you need. Understanding that structure - rather than generic HVAC trivia - is the difference between a candidate who wastes weeks studying the wrong material and one who walks in prepared.
For a broader orientation to the terminology, see our companion pieces on What Is AZ-ACR?, AZ-ACR Meaning, and What Does AZ-ACR Stand For?.
Who Administers the Exam and Why It Matters
The Arizona Registrar of Contractors sets licensing policy, but the day-to-day testing is handled by PSI Services LLC, a third-party testing vendor. PSI publishes two key documents candidates should know about: the R-39R/C-39 (CR-39) trade outline (last revised June 8, 2023) and the general PSI Arizona Contractors Candidate Information Bulletin (dated February 18, 2026). The trade outline tells you what's on the test; the bulletin tells you how testing day actually works - check-in, calculator rules, remote-proctoring restrictions, and identification requirements.
Because ROC relies on statute to define eligibility, two Arizona Revised Statutes sections are directly relevant: ARS §32-1122, which governs qualifying party experience requirements, and ARS §32-1123.01, which governs how long exam results remain valid for licensing purposes. Candidates researching prerequisites should read our dedicated breakdown at AZ-ACR Requirements 2026: Eligibility, Prerequisites & How to Qualify.
Exam Format, Timing, and Fees
The R-39R/C-39 (CR-39) trade exam is delivered as computer-based multiple choice, and candidates can choose either an in-person test-center session or remote-proctored testing from an approved location. Key mechanics:
- Question count: 80 scored questions, per the official outline.
- Experimental items: PSI may insert 5 to 10 additional unscored questions within the same time window - these are indistinguishable from scored questions, so every question must be treated seriously.
- Time limit: 210 minutes total.
- Passing score: 70% correct on scored items.
- Trade exam fee: $66 per attempt.
- Statutes and Rules Exam (SRE): a separate online exam covering Arizona law and rules, priced at $61 - distinct from the trade exam fee and requiring its own preparation track.
For a full pricing walkthrough including how these fees interact with license and bond costs, see AZ-ACR Certification Cost 2026: Complete Pricing Breakdown. And if you're wondering exactly how the 70% threshold translates into a raw number of correct answers, our article on AZ-ACR Passing Score 2026: Exactly What You Need to Pass works through the math.
Key Takeaway
Treat every question on the exam as scored, since experimental items are unlabeled - pacing yourself across 210 minutes for 80+ questions means budgeting roughly two and a half minutes per question, with room for review.
The 12 Domains and Their Question Weights
Unlike vague "know HVAC" study advice, the AZ-ACR trade outline is refreshingly specific about what to expect. There are twelve domains, and the official question allocations are fixed:
| Domain | Subject Area | 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 at 12 questions apiece - together they make up nearly half the scored exam. A candidate who under-studies any one of these three at the expense of the others is taking an unnecessary risk, since the outline gives them equal weight rather than favoring one system type over another.
Refrigeration, Air Conditioning, and Warm Air Heating
These three domains anchor the exam and deserve balanced attention rather than a single favorite subject.
- Refrigeration cycle components, refrigerant behavior, and system troubleshooting logic
- Air conditioning equipment sizing, airflow, and component diagnosis
- Warm air heating equipment types, combustion basics, and venting principles
Controls and Motors
At 8 questions, this is the largest domain outside the "big three," covering electrical controls, motor types, and their integration with HVAC/R equipment.
- Thermostats, relays, and safety control logic
- Motor types and their application in fans, compressors, and blowers
The mid-weighted domains - Fuel Piping Systems, Water Piping Systems, Steam/Hot/Chilled/Condensing Water, and Testing, Balancing, and Inspections - each carry 5 questions, while Boilers, Ventilation, Evaporative Coolers, and Sizing and Estimating each carry 4. None of these smaller domains should be skipped; collectively they represent over a quarter of the scored exam. For a deep dive into each of the twelve areas with topic-level detail, read AZ-ACR Exam Domains 2026: Complete Guide to All 12 Content Areas.
What You Can (and Can't) Bring Into the Test
The R-39R/C-39 (CR-39) exam is open-book, but only for a defined list of references. Approved materials 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
Other textbooks named in the trade outline are study-only references - they help you learn the material but cannot be brought into the exam room or used during a remote session. Candidates are allowed to prepare their approved references in advance with highlighting, underlining, annotations, and permanent tabs. What's prohibited is bringing in loose additional papers or writing in the references during the actual test session.
Remote-proctored sessions carry additional restrictions worth noting: no scratch paper and no breaks are permitted during remote testing. The general bulletin does allow a silent, nonprinting, nonprogrammable, nonscientific calculator for either delivery method.
Who Qualifies to Sit for the Exam
Arizona ROC generally requires the qualifying party to have four years of practical or management experience in the trade, including two years within the preceding ten years. Qualifying technical training can substitute for up to two of those four years. Once you pass, the results must fall within the two years preceding your license application - so timing your exam relative to your licensing paperwork matters.
These are eligibility mechanics, not exam-day mechanics, so they're covered in full detail in AZ-ACR Requirements 2026: Eligibility, Prerequisites & How to Qualify. If you're still deciding whether to pursue this path at all, our ROI-focused piece Is the AZ-ACR Certification Worth It? Complete ROI Analysis 2026 and our earnings overview at AZ-ACR Salary Guide 2026: Complete Earnings Analysis can help frame the decision.
Retake Waiting Periods
Not everyone passes on the first attempt, and Arizona's rules build in structured waiting periods rather than allowing immediate retesting. A failed attempt requires a 30-day wait before scheduling again. If a candidate reaches a fourth or later attempt, the waiting period extends to 90 days. This structure rewards focused preparation over repeated guessing, and it's part of why understanding domain weights before your first attempt is so valuable - a failed first try costs both the $66 fee again and a month of lost time.
To gauge realistically how challenging the exam tends to be for candidates and what causes people to need a retake, see How Hard Is the AZ-ACR Exam? Complete Difficulty Guide 2026 and AZ-ACR Pass Rate 2026: What the Data Shows.
Who Actually Needs This Certification
The R-39R/C-39 (CR-39) exam is aimed at the qualifying party for an Arizona residential/commercial air conditioning and refrigeration contracting license - typically someone who wants to run or legally qualify an HVAC/R contracting business in the state, or a technician moving into that role. This includes people working across both residential and commercial installation and service, since the "R/C" designation in the license classification spans both.
Employers and licensing boards care about this exam because it verifies competency across the full breadth of systems a licensed contractor might be responsible for: not just cooling, but heating, boilers, piping, ventilation, and even sizing and estimating work for bids. That breadth is exactly why the domain list runs to twelve categories instead of two or three.
If you're evaluating career paths tied to this license, our jobs-focused article at AZ-ACR Jobs and training options at AZ-ACR Training go into more depth on the employment side.
Building a Domain-Aware Study Plan
Generic study techniques like spaced repetition or timed practice sessions only help if they're pointed at the right material. Because the trade outline weights domains unevenly, an efficient study sequence spends the most calendar time on Refrigeration, Air Conditioning, and Warm Air Heating, moderate time on Controls and Motors, and lighter - but not zero - time on the eight smaller domains.
Refrigeration and Air Conditioning
- Refrigeration cycle, refrigerant properties, and diagnostic logic
- Air conditioning equipment sizing, airflow, and component function
Warm Air Heating and Controls/Motors
- Combustion, venting, and warm air equipment types
- Electrical controls, relays, thermostats, and motor applications
Piping, Water, and Steam Systems
- Fuel piping and water piping fundamentals
- Steam, hot, chilled, and condensing water systems
Remaining Domains and Open-Book Practice
- Boilers, ventilation, evaporative coolers, and sizing/estimating
- Tab and practice navigating the 2018 IFGC and 2018 IMC
For a more detailed week-by-week study framework tied specifically to this exam's structure, see AZ-ACR Study Guide 2026: How to Pass on Your First Attempt. And if you want a compact one-page reference for last-minute review, check out AZ-ACR Cheat Sheet 2026: One-Page Review of Must-Know Facts.
You can also sharpen exam-day timing and question familiarity using realistic practice questions on our main practice test platform, which mirrors the domain distribution described in the official outline rather than generic HVAC trivia.
After You Pass: License and Renewal
Passing the trade exam is one piece of the licensing puzzle. Candidates also need the separate Statutes and Rules Exam ($61), must meet the experience requirements under ARS §32-1122, and must apply for licensure within two years of their exam results per ARS §32-1123.01. Once licensed, Arizona contractor licenses renew biennially, and license fees plus bond obligations are handled separately from exam fees - they are not part of the $66 trade exam or $61 SRE cost.
Before you schedule, it's worth confirming current testing windows and any scheduling deadlines through AZ-ACR Exam Dates 2026: Testing Windows, Deadlines & Scheduling, since PSI periodically updates its candidate bulletin.
Frequently Asked Questions
No. On this site, AZ-ACR refers specifically to the Arizona R-39R/C-39 (CR-39) trade examination administered through PSI on behalf of the Arizona Registrar of Contractors. It is a state licensing exam, not a national manufacturer or industry-association credential.
The official outline specifies 80 scored questions with a 210-minute time limit and a 70% passing requirement. PSI may also insert 5 to 10 unscored experimental questions within that same time window.
Refrigeration, Air Conditioning, and Warm Air Heating are the joint-largest subject areas, each contributing 12 questions. Controls and Motors follows with 8 questions, and the remaining eight domains carry either 4 or 5 questions each.
Only specific references are approved for open-book use during the exam: OSHA 29 CFR Part 1926 (or PSI's selections with the latest amendments), the 2018 International Fuel Gas Code, and the 2018 International Mechanical Code. Other textbooks listed in the trade outline are for study purposes only and cannot be used during testing.
You must wait 30 days before retaking the exam. If you reach your fourth or a later attempt, the required waiting period increases to 90 days before you can test again.