Oklahoma HVACR Unlimited Contractor Highlighted & Tabbed Book Package

Prepare for the Oklahoma HVACR Unlimited Contractor examination with an organized collection of highlighted and tabbed reference materials covering mechanical codes, fuel gas requirements, refrigeration and air conditioning, commercial load calculations, air distribution, trade mathematics, and construction safety.

The Oklahoma HVACR Unlimited Contractor Highlighted & Tabbed Book Package includes a Ductulator, the International Mechanical Code, 2018; International Fuel Gas Code, 2018; Modern Refrigeration and Air Conditioning, 22nd Edition; Manual N - Commercial Load Calculation for Small Commercial Buildings, 5th Edition; Mathematics for Plumbers and Pipefitters, 8th Edition; and Code of Federal Regulations - 29 CFR Part 1926 (OSHA).

The included books are highlighted and tabbed to support organized study and faster reference navigation. Since the Oklahoma HVACR Contractor Unlimited examination is open book, familiarity with the approved references can be an important part of preparation. Candidates should understand both the HVACR material and how to locate chapters, tables, code provisions, formulas, definitions, and technical information efficiently.

The Oklahoma HVACR Unlimited Contractor classification covers qualifying HVACR work without the equipment-capacity restrictions associated with Oklahoma's limited HVACR contractor classification. Candidates preparing for this license should expect broad technical coverage involving residential and commercial systems, air distribution, refrigeration, heating, electrical controls, natural gas, mechanical codes, commercial load calculations, and safety.

Please allow up to 15 business days for highlighted and tabbed book package orders.

Exam Details

The Oklahoma HVACR Contractor Unlimited examination tests knowledge associated with the installation, maintenance, repair, fabrication, alteration, and extension of air conditioning, refrigeration, heating, and ventilation systems. The scope includes ductwork within complete systems without the horsepower or tonnage limitations associated with the limited HVACR classification.

• Exam: Oklahoma HVACR Contractor Unlimited
• Testing Provider: PSI
• Number of Questions: 90
• Time Allowed: 240 minutes
• Passing Score: 70%
• Passing Raw Score: 63 correct answers
• Exam Format: Open book

The technical examination contains 15 questions in Electrical Knowledge and Controls, 12 questions in Natural Gas, 25 questions in Air Distribution Systems, 20 questions in Refrigeration and Air Conditioning Systems, 15 questions in Heating Systems, and 3 questions in Safety.

Air Distribution Systems is the largest individual section. Preparation should include duct definitions, sizing and design, assembly and installation, hangers and supports, duct materials and shapes, insulation, fire and smoke control, hoods and exhaust systems, testing and balancing, ventilation requirements, plans, and symbols.

Refrigeration and Air Conditioning Systems covers refrigeration theory, refrigerants, equipment sizing and design, components, piping, equipment installation, system operation, troubleshooting, and maintenance. Heating Systems includes heating theory, combustion air, vents and chimneys, equipment sizing, heating equipment, installation, operation, maintenance, troubleshooting, hydronics, and hydronic piping.

Electrical Knowledge and Controls includes electrical theory, motors, DC circuits, AC circuits, and controls. Natural Gas includes piping valves, connectors, accessories, hangers and supports, sizing, materials, and testing. Safety topics include personal protective equipment, fall protection, ladders, scaffolds, lockout/tagout, first aid, ventilation, employee training, and other workplace safety subjects.

Open Book Test

The Oklahoma HVACR Contractor Unlimited examination is an open book test. Candidates may bring approved reference materials into the examination center according to PSI testing rules.

Approved reference materials may be highlighted, underlined, and indexed before the examination. Permanent tabs are permitted. Temporary tabs such as Post-it notes are not allowed, and candidates may not write notes in their references before or during the examination.

The highlighted and tabbed format of this package supports the reference-navigation skills needed for an open-book exam. Highlighting can draw attention to useful provisions and technical information, while permanent tabs can help candidates move between important chapters and subject areas more efficiently.

Open book does not mean every question should be researched from the beginning. Candidates have 240 minutes for 90 questions, so effective time management matters. Some questions may be answered from trade knowledge, while others may require a code section, calculation, table, or technical reference.

A mechanical installation, ventilation, or duct question may direct you toward the International Mechanical Code. Fuel gas sizing, materials, appliances, combustion air, or venting may require the International Fuel Gas Code. Commercial load-calculation questions may involve Manual N, while air-distribution calculations may involve the Ductulator.

Modern Refrigeration and Air Conditioning supports broader technical preparation involving refrigeration, heating, controls, equipment, system operation, installation, troubleshooting, and maintenance. Mathematics for Plumbers and Pipefitters supports trade calculations, while 29 CFR Part 1926 supports construction safety preparation.

Modern Refrigeration and Air Conditioning, 22nd Edition is permitted for the applicable PSI examination beginning August 13, 2026.

Licensing Steps

1. Gain qualifying mechanical trade experience. Build verifiable HVACR experience appropriate to the unlimited contractor category.
2. Meet contractor qualifications. Oklahoma mechanical contractor applicants must satisfy the applicable journeyman qualifications and obtain an additional year of experience in the mechanical trade.
3. Demonstrate unlimited-level HVACR experience. Experience used to qualify for HVACR Unlimited licensing must demonstrate work above the capacity limitations associated with the HVACR Limited classification.
4. Submit the mechanical contractor application. Apply through the Oklahoma Construction Industries Board for the HVACR Unlimited Contractor category.
5. Receive approval to test. The Construction Industries Board determines whether an applicant meets the qualifications necessary to proceed with contractor testing.
6. Schedule the required examination. Approved candidates complete the applicable examination scheduling process through PSI.
7. Complete the contractor examination requirements. Prepare for and complete the technical and applicable contractor business and law testing requirements.
8. Complete active contractor requirements. After satisfying examination requirements, complete Oklahoma's applicable requirements for active mechanical contractor status.

The exam is an important part of the process, but preparation should also include understanding the license scope and administrative requirements associated with becoming an Oklahoma HVACR Unlimited Contractor.

State Requirements

The Oklahoma HVACR Unlimited Contractor classification authorizes qualifying work involving cooling products, systems, or equipment, including process piping, without the tonnage limitations associated with the HVACR Limited classification.

The unlimited classification also covers heating equipment and related process piping without the heating-input restriction that applies to the limited classification. It additionally includes qualifying sheet metal, natural gas piping, and refrigeration work.

Oklahoma mechanical contractor applicants must meet the same general qualification requirements applicable to a journeyman and obtain an additional year of mechanical trade experience. Experience used to qualify for the HVACR Unlimited classification must demonstrate work above the capacity thresholds associated with the limited classification.

A mechanical contractor must also be a permanent employee, owner, partner, or officer of the mechanical firm. Candidates pursuing contractor licensing should plan for qualifying experience, application review, testing, and active-license requirements as part of the complete licensing process.

Reference Books

• Ductulator
  A practical air-distribution tool used for duct-sizing work. It supports preparation involving airflow, duct dimensions, friction, velocity, and other relationships used when working with air distribution systems.
• International Mechanical Code, 2018
  Covers mechanical equipment, ventilation, duct systems, exhaust systems, refrigeration, combustion air, chimneys, vents, and other mechanical installation requirements. The highlighted and tabbed format can help candidates practice locating code provisions efficiently.
• International Fuel Gas Code, 2018
  Covers fuel gas piping, sizing, materials, installation, appliances, connectors, testing, combustion air, venting, and related requirements. This reference supports natural gas and heating-related preparation.
• Modern Refrigeration and Air Conditioning, 22nd Edition
  Provides comprehensive HVACR technical coverage involving refrigeration theory, refrigerants, heating, air conditioning, electrical fundamentals, motors, controls, equipment, piping, installation, operation, maintenance, service, and troubleshooting.
• Manual N - Commercial Load Calculation for Small Commercial Buildings, 5th Edition
  Supports preparation involving heating and cooling load calculations for small commercial buildings. This resource is especially relevant to candidates preparing for an unlimited HVACR classification where commercial system knowledge is important.
• Mathematics for Plumbers and Pipefitters, 8th Edition
  Provides trade-oriented mathematics covering measurements, formulas, conversions, area, volume, piping calculations, and other practical mathematical concepts used in mechanical work.
• Code of Federal Regulations - 29 CFR Part 1926 (OSHA)
  Contains federal construction-industry safety requirements involving personal protective equipment, workplace hazards, fall protection, ladders, scaffolds, employee protection, and other jobsite safety subjects.

Exam Room Approved Books

The references included in this package are approved materials associated with the Oklahoma HVACR Contractor Unlimited examination: the ACCA Ductulator, International Mechanical Code 2018, International Fuel Gas Code 2018, Modern Refrigeration and Air Conditioning, Manual N, Mathematics for Plumbers and Pipefitters, and 29 CFR Part 1926 OSHA.

PSI bases code questions on the specific code editions identified for the examination. The applicable code references are the 2018 International Mechanical Code and 2018 International Fuel Gas Code with Oklahoma revisions.

For Modern Refrigeration and Air Conditioning, the 22nd Edition is permitted beginning August 13, 2026. Candidates should use the reference materials regularly throughout preparation so they understand not only what information the books contain but also how to navigate them efficiently.

Approved references may be highlighted, underlined, and indexed before testing. Permanent tabs are allowed under PSI's reference rules, making highlighted and tabbed books useful for candidates who want to develop a consistent navigation system during preparation.

Test Information and Study Materials

A strong Oklahoma HVACR Unlimited Contractor study plan should reflect the broad technical scope of the exam. Candidates should combine HVACR theory, commercial system knowledge, reference navigation, code study, mathematics, load calculations, air distribution, and safety preparation.

Air Distribution Systems represents 25 of the 90 examination questions, making it the largest content area. Review duct sizing and design, materials, installation, insulation, ventilation, exhaust systems, fire and smoke control, testing and balancing, and plans and symbols. Work with the Ductulator while studying these topics so air-distribution calculations become part of your regular preparation.

Refrigeration and Air Conditioning Systems accounts for another 20 questions. Review refrigeration principles, refrigerants, system components, equipment sizing, piping, installation, operation, troubleshooting, and maintenance. Use Modern Refrigeration and Air Conditioning while studying so you become familiar with where technical information is located.

Heating Systems and Electrical Knowledge and Controls each contain 15 questions. Heating preparation should cover combustion air, vents and chimneys, equipment sizing, hydronic systems, installation, operation, and maintenance. Electrical preparation should reinforce motors, circuits, controls, and basic electrical principles as they apply to HVACR equipment.

Natural Gas accounts for 12 questions. Practice locating requirements involving piping, materials, valves, connectors, supports, sizing, and testing in the International Fuel Gas Code.

Manual N should be incorporated into preparation for commercial load calculations. Candidates pursuing an unlimited contractor classification should be comfortable with commercial HVAC concepts and equipment-sizing principles in addition to residential knowledge.

Safety preparation should include direct use of 29 CFR Part 1926. Practice locating provisions related to fall protection, personal protective equipment, ladders, scaffolds, lockout/tagout, employee training, and workplace hazards.

Mixed-reference practice can make studying more realistic. Work through several different subject areas during one session. Start with a mechanical code question, move to air distribution, then refrigeration, fuel gas, commercial load calculations, mathematics, and OSHA safety. Before opening a reference, identify which resource is most likely to contain the information.

The highlighted and tabbed format can make this process more organized, but effective preparation still depends on understanding the material. Use the tabs as navigation tools while building technical knowledge and practicing efficient book use.

How 1 Exam Prep Helps You Reach Your Goal

1 Exam Prep supports Oklahoma HVACR Unlimited Contractor candidates through organized study guidance, trade-focused review, practice-oriented preparation, reference navigation, and confidence-building study structure.

The highlighted and tabbed books in this package provide an organized starting point for studying the technical areas associated with unlimited HVACR contractor testing. Candidates can work with mechanical codes, fuel gas requirements, commercial load calculations, refrigeration and heating material, trade mathematics, air distribution, and OSHA safety in a structured way.

Reference navigation is an important part of open-book preparation. 1 Exam Prep encourages candidates to use their books while studying rather than saving them only for exam day. Repeated practice can help you learn which reference applies to each subject and where important information is located.

Trade-focused review can also help identify weaker areas. An experienced technician may be confident with refrigeration and equipment installation but need additional practice with commercial load calculations, electrical controls, fuel gas codes, duct sizing, or OSHA safety requirements.

Organizing preparation around the actual examination subjects helps candidates focus their study time more effectively. The goal is to build stronger familiarity with both HVACR concepts and the approved references so candidates can approach the Oklahoma HVACR Unlimited Contractor examination with confidence developed through consistent preparation and practice.

FAQ Section

What is included in the Oklahoma HVACR Unlimited Contractor Highlighted & Tabbed Book Package?

The package includes a Ductulator, International Mechanical Code 2018, International Fuel Gas Code 2018, Modern Refrigeration and Air Conditioning 22nd Edition, Manual N 5th Edition, Mathematics for Plumbers and Pipefitters 8th Edition, and 29 CFR Part 1926 OSHA.

Are the included books highlighted and tabbed?

Yes. The included books are highlighted and tabbed to support organized study and more efficient reference navigation.

How long should I allow for my order?

Please allow up to 15 business days for highlighted and tabbed book package orders.

Is the Oklahoma HVACR Unlimited Contractor examination open book?

Yes. The examination is open book and allows approved references under PSI testing rules.

How many questions are on the Oklahoma HVACR Unlimited Contractor exam?

The examination contains 90 questions. Candidates receive 240 minutes to complete the exam.

What score is required to pass?

The passing score is 70 percent, which corresponds to 63 correct answers on the 90-question examination.

What is the largest exam content area?

Air Distribution Systems is the largest content area with 25 questions. Refrigeration and Air Conditioning Systems follows with 20 questions.

Is Manual N included?

Yes. Manual N - Commercial Load Calculation for Small Commercial Buildings, 5th Edition is included to support commercial HVAC load-calculation preparation.

Is a Ductulator included?

Yes. The package includes a Ductulator for air-distribution and duct-sizing preparation.

Can I use Modern Refrigeration and Air Conditioning, 22nd Edition?

PSI permits Modern Refrigeration and Air Conditioning, 22nd Edition beginning August 13, 2026.

What is the difference between Oklahoma HVACR Limited and Unlimited Contractor licensing?

The HVACR Limited classification has capacity restrictions for cooling and heating equipment. The HVACR Unlimited classification does not have those equipment-size restrictions.

How should I prepare with highlighted and tabbed books?

Use the books with technical review and practice questions. Learn which reference applies to each subject and practice locating chapters, code sections, tables, formulas, calculations, and safety requirements efficiently.