- Blueprint Overview: Where the 90 Questions Come From
- Full 17-Domain Breakdown Table
- The Big Four Technical Domains
- Mid-Weight Technical Domains
- The Business, Law, and Admin Cluster
- Building a Study Schedule Around Domain Weight
- Format, References, and Open-Book Rules
- Registration, Eligibility, and Retake Mechanics
- FAQ
- The 90-question exam covers 17 domains with weights ranging from 1 to 14 questions each.
- General Knowledge and Systems & Sizing tie as the largest domains at 14 questions apiece.
- Piping and Maintenance/Troubleshooting each carry 13 questions - together with the two largest domains, they form more than half the exam.
- Ten business and legal domains (Business Organization through Licensing Laws) collectively add roughly two dozen questions.
Blueprint Overview: Where the 90 Questions Come From
The Alabama Board of Heating, Air Conditioning & Refrigeration Contractors administers what it calls the Refrigeration Contractors Examination, delivered through testing provider Prov, Inc. under the exam title "Refrigeration." Candidates preparing for the commercial refrigeration contractor exam need to understand one thing above all else: the test is not evenly distributed. Some of the 17 domains barely register on the blueprint, while a handful of them make up the bulk of your score.
Per the Prov candidate bulletin revised September 4, 2026, the exam consists of 90 computer-based multiple-choice questions, delivered under a 4-hour time limit, with a passing score of 70%. Every one of the 17 content areas listed in the official blueprint receives a fixed number of questions - no domain is skipped, and no domain dominates so heavily that you can ignore the rest. Still, allocation matters enormously for how you spend study hours. If you're still mapping out your overall strategy, the companion resource on the AL-REFRIG Study Guide 2026: How to Pass on Your First Attempt walks through a full first-attempt plan; this article focuses specifically on what's inside each of the 17 content areas and how many questions ride on each one.
Full 17-Domain Breakdown Table
Below is the official question allocation across all 17 domains, in blueprint order. These numbers come directly from the Prov candidate bulletin and sum to the full 90-question exam.
| # | Domain | Questions |
|---|---|---|
| 1 | General Knowledge | 14 |
| 2 | Piping | 13 |
| 3 | Systems & Sizing | 14 |
| 4 | Maintenance/Troubleshooting | 13 |
| 5 | Plan Reading | 2 |
| 6 | Electrical Applications for Refrigeration Systems | 8 |
| 7 | Business Organization | 1 |
| 8 | Risk Management | 2 |
| 9 | Project Management | 2 |
| 10 | Estimating | 3 |
| 11 | Safety and Environmental | 2 |
| 12 | Labor Laws | 2 |
| 13 | Payroll and Employment Taxes | 3 |
| 14 | Financial Management | 3 |
| 15 | Contracts | 2 |
| 16 | Lien Laws | 2 |
| 17 | Licensing Laws | 4 |
Notice the shape of this table: four domains carry double-digit question counts, one domain (Electrical Applications) sits in a distinct middle tier at 8 questions, and the remaining twelve domains each contribute between 1 and 4 questions. That shape should directly inform how you allocate study time - a topic explored in more depth in AL-REFRIG Exam Domains 2026: Complete Guide to All 17 Content Areas.
The Big Four Technical Domains
General Knowledge, Systems & Sizing, Piping, and Maintenance/Troubleshooting together account for 54 of the exam's 90 questions - well over half the exam. Mastering these four areas is the single highest-leverage thing a candidate can do.
Domain 1: General Knowledge (14 questions)
This domain tests broad familiarity with commercial refrigeration principles, terminology, and fundamental concepts that cut across the entire trade. Tied for the single largest domain on the exam, it rewards candidates who understand refrigeration cycles, component function, and industry vocabulary at a practical, field-level depth rather than a purely academic one.
- Core refrigeration cycle stages and how components interact
- Terminology consistency across code references and manufacturer documentation
- Foundational concepts that reappear inside other domains, including Piping and Systems & Sizing
Domain 3: Systems & Sizing (14 questions)
Equal in weight to General Knowledge, this domain focuses on selecting and sizing refrigeration equipment for commercial applications - matching load requirements to compressor, condenser, and evaporator capacity, and understanding how system components must be proportioned to work together reliably.
- Load calculation logic and capacity matching between components
- System configuration choices for different commercial refrigeration setups
- Sizing judgment calls that a contractor would actually make on a job
Domain 2: Piping (13 questions)
Piping design, materials, sizing, and installation practice for refrigeration systems. This domain overlaps conceptually with both the 2021 International Mechanical Code and general system design, so candidates should expect questions that connect code requirements to real piping layout decisions.
- Piping material selection and sizing logic
- Installation practices that affect system efficiency and longevity
- Code-driven constraints on refrigerant piping runs
Domain 4: Maintenance/Troubleshooting (13 questions)
Diagnostic reasoning and preventive maintenance for commercial refrigeration equipment. Expect scenario-style questions that describe a symptom or fault condition and ask you to identify the most probable cause or the correct corrective action.
- Systematic fault-diagnosis logic rather than rote memorization
- Preventive maintenance schedules and their rationale
- Common failure patterns in commercial refrigeration components
Key Takeaway
If your study time is limited, prioritize General Knowledge, Systems & Sizing, Piping, and Maintenance/Troubleshooting first - they represent 54 of 90 questions, meaning weakness here is mathematically the hardest to overcome with strength elsewhere.
Mid-Weight Technical Domains
Three domains sit in a distinct middle tier: substantial enough to require real study time, but nowhere near the weight of the big four.
Domain 6: Electrical Applications for Refrigeration Systems (8 questions)
The clear middle-weight domain on the blueprint. This area covers electrical components, wiring, and controls as they specifically apply to refrigeration equipment, and it draws on the 2020 NFPA 70 National Electrical Code, which appears in both the Board's and Prov's reference lists.
- Motor controls, relays, and safety switches used in refrigeration circuits
- Electrical code requirements applicable to refrigeration installations
- Wiring diagrams and how to interpret them under exam conditions
Domain 5: Plan Reading (2 questions) & Domain 11: Safety and Environmental (2 questions)
Plan Reading tests your ability to interpret mechanical drawings and specifications for refrigeration installations. Safety and Environmental covers workplace safety practice and environmental handling requirements relevant to refrigerants and equipment. Neither carries heavy weight individually, but both are practical, field-relevant topics worth a focused review pass rather than deep study time.
The Business, Law, and Admin Cluster
Business and law topics are explicitly included in this examination, and they show up as ten separate low-weight domains that collectively add up fast. Individually, none of these domains looks intimidating - most carry only 1 to 4 questions. But add them together and you get roughly two dozen questions spread across Business Organization, Risk Management, Project Management, Estimating, Labor Laws, Payroll and Employment Taxes, Financial Management, Contracts, Lien Laws, and Licensing Laws.
| Domain | Questions | Core Focus |
|---|---|---|
| Business Organization | 1 | Business structure basics for contractors |
| Risk Management | 2 | Identifying and managing contractor risk exposure |
| Project Management | 2 | Managing refrigeration installation projects |
| Estimating | 3 | Bid and cost estimation for refrigeration work |
| Labor Laws | 2 | Employment law basics relevant to contractors |
| Payroll and Employment Taxes | 3 | Payroll obligations and employment tax handling |
| Financial Management | 3 | Financial oversight for contracting businesses |
| Contracts | 2 | Contract terms and obligations |
| Lien Laws | 2 | Mechanic's lien procedures in Alabama |
| Licensing Laws | 4 | Alabama licensing law and Board authority |
Licensing Laws, at 4 questions, is the largest domain in this cluster - larger than any single domain in Plan Reading, Safety and Environmental, Business Organization, Risk Management, Project Management, Contracts, or Lien Laws. Candidates who treat this whole cluster as an afterthought often leave several easy points on the table, because these topics tend to test recognition of concepts rather than deep calculation.
Building a Study Schedule Around Domain Weight
A domain-weighted study plan should mirror the blueprint, not treat all 17 areas equally. Here is one way to sequence preparation across several weeks, front-loading the heaviest domains while still leaving room for the business and law cluster before test day.
General Knowledge & Systems & Sizing
- Work through refrigeration cycle fundamentals and terminology
- Practice load-matching and sizing scenarios
Piping & Maintenance/Troubleshooting
- Review piping material and sizing rules against the 2021 IMC
- Drill diagnostic scenario questions for common fault patterns
Electrical Applications, Plan Reading, Safety and Environmental
- Study electrical controls and 2020 NFPA 70 references relevant to refrigeration
- Practice interpreting mechanical drawings and specs
Business, Law, and Admin Cluster
- Cycle quickly through all ten low-weight domains: Business Organization, Risk Management, Project Management, Estimating, Labor Laws, Payroll and Employment Taxes, Financial Management, Contracts, Lien Laws, Licensing Laws
- Run full-length timed practice sets under the 4-hour limit
For a deeper look at how difficult candidates generally find the exam and how the domain weighting affects that difficulty, see How Hard Is the AL-REFRIG Exam? Complete Difficulty Guide 2026. If you want to understand exactly what 70% means in terms of raw questions answered correctly across 90 items, check AL-REFRIG Passing Score 2026: Exactly What You Need to Pass.
Format, References, and Open-Book Rules
Understanding domain content is only half the picture - knowing exactly how the test is delivered changes how you prepare. The exam is open-book, available either at Prov test centers or remotely through Examroom after a system check. Only a simple four-function calculator is permitted; no scientific or graphing calculators are allowed.
Reference materials matter a great deal here, since domains like Piping, Electrical Applications, and Systems & Sizing lean on code references. The 2021 International Mechanical Code and the 2020 NFPA 70 National Electrical Code appear on both the Board's and Prov's reference lists, but the two lists differ on other titles and editions. Confirm accepted books with Prov before purchasing anything, and don't assume every code book you already own will be allowed in the room.
- Highlighting, permanent tabs, and formulas handwritten in ink are permitted
- Handwritten notes beyond formulas, movable tabs, added photocopied sheets, and outside exam-prep guides are prohibited
Using a focused practice resource before test day - like the timed practice sets on the AL-REFRIG practice test platform - helps you get comfortable navigating 90 questions under the 4-hour limit without wasting time flipping through reference books mid-exam.
Registration, Eligibility, and Retake Mechanics
Domain content only matters once you're eligible to sit for the exam. Under Code of Alabama section 34-31-28(c), eligibility requires either 3,000 hours of qualifying work experience or graduation from an approved heating, air conditioning, or refrigeration curriculum. Work-experience applicants submit notarized employer affidavits with corresponding W-2s; curriculum applicants submit graduation documentation, and citizenship or lawful-presence documentation is required from everyone. Board approval must happen before you can schedule with Prov, and eligibility lasts one year from application approval.
The written examination fee is $175, non-refundable and paid to the Board, with a 4% service fee added for credit-card payments. If you cancel or reschedule, do it with Prov at least 3 business days before your appointment or you forfeit the fee. A failed written attempt requires submitting Form EA-5 or using the Board re-examination portal and paying another $175. Under Rule 440-X-3-.07, the Board may approve a $375 practical examination after a failed written attempt upon written request; it's not