Connecticut Limited Warm Air, Air Conditioning and Refrigeration System Journeyperson (D-2) - Books & Courses Rental Package

Prepare for the Connecticut Limited Warm Air, Air Conditioning and Refrigeration System Journeyperson (D-2) examination with a comprehensive rental package that combines highlighted and tabbed reference books, a Ductulator, and structured online course access. This package is designed for candidates who want an organized approach to studying technical HVAC subjects while practicing with the same included references throughout their preparation.

The Connecticut D-2 examination covers warm-air heating, air conditioning, refrigeration systems, fuel-gas systems, ductwork, controls, ventilation, heat pumps, furnaces, chillers, safety, combustion air, and related mechanical knowledge. Candidates must understand practical trade concepts and be able to locate code provisions, technical explanations, sizing information, diagrams, definitions, and tables during a timed open-book examination.

This Books & Courses Rental Package includes the International Mechanical Code, 2021; NFPA 54 - National Fuel Gas Code Handbook, 2012; Modern Refrigeration and Air Conditioning, 22nd Edition; a Ductulator; HVAC Duct Construction Standards, Metal and Flexible, 2005, 3rd Edition; and NFPA 58 - Liquefied Petroleum Gas Code, 2014.

All included books are highlighted and permanently tabbed before delivery. Important chapters, definitions, mechanical requirements, fuel-gas provisions, refrigeration subjects, duct-construction topics, equipment information, technical tables, and commonly reviewed sections are marked to create a practical starting point for study.

The included online course provides 6 months of course access. Candidates can use the course to review the D-2 examination outline, reinforce trade knowledge, complete practice-oriented preparation, and improve open-book reference-navigation skills.

The rental cost is $1,890. A refundable book deposit of $750 is also required, making the total package price $2,640. The $750 deposit is refundable when all rental books are returned within the rental period in similar condition.

Please allow up to 15 business days for book & course rental package orders.

Exam Details

The Connecticut Limited Warm Air, Air Conditioning and Refrigeration System Journeyperson (D-2) examination contains 60 questions. Candidates are allowed two hours to complete the examination, and a minimum score of 70 percent is required to pass.

The D-2 examination content outline includes the following categories:

• Insulation: 1 question
• Hangers and Supports: 2 questions
• Sound, Vibration and Seismic Control: 1 question
• Heating and Cooling Principles: 5 questions
• Refrigerants and Refrigeration: 8 questions
• Testing, Adjusting and Balancing: 1 question
• Controls: 3 questions
• Machine Room: 1 question
• Air-Conditioning and Heat-Pump Equipment: 5 questions
• Furnaces and Heaters: 4 questions
• Chimneys, Flues and Vents: 2 questions
• Combustion Air: 2 questions
• Fuel Gas Systems: 10 questions
• Ducts: 6 questions
• Chillers: 2 questions
• Ventilation and Exhaust: 3 questions
• Safety: 4 questions

Fuel-gas systems are the largest examination category, accounting for 10 of the 60 questions. Candidates should understand fuel-gas piping, sizing, pressure, regulators, appliance connections, testing, combustion air, venting, and related installation and safety principles.

Gas-pipe sizing questions require use of the longest-length method. Candidates should practice identifying system demand, selecting the correct table, determining the longest measured length, and applying that length consistently when sizing branches within the system.

Refrigerants and refrigeration account for eight questions. Preparation should include refrigeration-cycle principles, compressors, condensers, evaporators, metering devices, refrigerants, pressure-temperature relationships, charging concepts, system operation, maintenance, and troubleshooting.

Ducts account for six questions. Candidates should review duct sizing, airflow, friction rate, velocity, fittings, materials, reinforcement, sealing, supports, and air-distribution performance. The included Ductulator and duct-construction standard support preparation for these subjects.

Heating and cooling principles and air-conditioning and heat-pump equipment each account for five questions. Candidates should understand heat transfer, sensible and latent heat, airflow, heating and cooling cycles, heat-pump operation, and the functions of common system components.

Furnaces and heaters and safety each account for four questions. Controls and ventilation and exhaust each account for three questions. Candidates should also review chimneys, flues, vents, combustion air, chillers, insulation, testing, balancing, machinery rooms, hangers, supports, sound, vibration, and seismic control.

With 120 minutes available for 60 questions, candidates have an average of two minutes per question. This time includes reading the question, identifying the subject, selecting the appropriate reference, locating the supporting information, and choosing an answer.

Open Book Test

The Connecticut D-2 Limited Warm Air, Air Conditioning and Refrigeration System Journeyperson examination is an open-book test. Candidates may bring approved references and permitted tools into the testing center under the applicable examination rules.

The International Mechanical Code supports preparation for mechanical equipment, refrigeration machinery rooms, ventilation, ducts, combustion air, chimneys, vents, and related installation requirements. NFPA 54 supports natural-gas questions, while NFPA 58 addresses liquefied petroleum gas systems.

Modern Refrigeration and Air Conditioning supports technical questions involving refrigeration, heating, air conditioning, heat pumps, controls, equipment operation, maintenance, and troubleshooting. HVAC Duct Construction Standards supports duct materials, construction, reinforcement, fittings, sealing, and supports. The Ductulator supports duct-sizing calculations.

Approved references may be highlighted, underlined, annotated, and indexed before the examination. Permanent tabs may be used to identify chapters, definitions, tables, fuel-gas provisions, refrigeration topics, ductwork subjects, equipment information, and other useful sections.

Temporary tabs, removable notes, loose papers, and inserted pages are not permitted. Candidates may not write in the references during the examination, and examination questions or answers may not be recorded inside approved materials.

All included books arrive highlighted and permanently tabbed. Candidates should review every tab before test day, study the highlighted material, and learn how each reference is organized. Prepared books are most useful when the candidate understands the subject connected to each marked section.

A practical open-book strategy begins by identifying the main subject. A mechanical-installation question may lead to the International Mechanical Code. A natural-gas piping, appliance, combustion-air, or venting question may lead to NFPA 54. An LP gas question may require NFPA 58.

Questions involving refrigeration principles, heat pumps, air-conditioning equipment, furnaces, controls, maintenance, or troubleshooting may be supported by Modern Refrigeration and Air Conditioning. Duct-construction questions may require HVAC Duct Construction Standards, while duct-sizing questions may involve the Ductulator.

Candidates should use permanent tabs together with the table of contents, index, chapter headings, diagrams, and technical tables. Reading the complete section is important because exceptions, notes, definitions, and surrounding material may affect the correct answer.

Timed reference practice can help candidates learn when to search a book and when to rely on established trade knowledge. It can also improve the ability to recognize which reference applies before valuable testing time is spent opening the wrong source.

Licensing Steps

1. Review the D-2 license scope. Confirm that the Connecticut Limited Warm Air, Air Conditioning and Refrigeration System Journeyperson classification matches the work you intend to perform.
2. Complete the qualifying training pathway. Complete a registered apprenticeship program or an equivalent experience-and-training pathway accepted by Connecticut.
3. Gather supporting records. Prepare apprenticeship completion documents, classroom records, employment verification, and other materials required for the selected application route.
4. Complete the journeyperson application. Submit the applicable D-2 application, supporting documentation, and required state fees to the Connecticut Department of Consumer Protection.
5. Receive examination eligibility. Connecticut reviews the applicant’s qualifications and determines whether the candidate may proceed to testing.
6. Prepare for the examination. Use the highlighted and tabbed rental books with six months of course access to review the D-2 examination outline.
7. Practice reference navigation. Learn which book applies to each subject and practice locating definitions, tables, diagrams, and technical requirements under timed conditions.
8. Schedule the D-2 examination. Follow the testing provider’s registration and scheduling instructions after receiving eligibility.
9. Complete the examination. Take the 60-question D-2 examination within the two-hour testing period.
10. Complete license-issuance requirements. Submit any remaining examination results, documents, or licensing fees required by Connecticut.
11. Return the rental books. Return all included rental books within the rental period in similar condition to qualify for the refundable $750 deposit.

Passing the examination does not automatically issue the D-2 license. Applicants must complete Connecticut’s training, application, examination, documentation, and license-issuance requirements.

State Requirements

The Connecticut D-2 credential is a limited journeyperson license for warm-air heating, air-conditioning, and refrigeration system work. The holder may perform qualifying installation, repair, replacement, maintenance, and alteration work within the scope of the credential.

The classification includes necessary piping for conveying heating or cooling media and associated pumping equipment. It also includes qualifying LP gas supplied by containers, natural-gas piping, approved gas appliances, gas-utilization equipment, and related accessories.

The D-2 license does not include the installation or servicing of oil burners of any size. License holders must remain within the work authorized by the credential and obtain any additional occupational license required for services outside the D-2 scope.

Sheet-metal work is included only as it relates to the limitations of the D-2 credential. The license does not provide unlimited authority to perform unrelated sheet-metal, plumbing, electrical, oil-burner, or other regulated work.

The D-2 license is a journeyperson credential and does not provide independent contracting authority. The holder performs authorized work while employed by or under the supervision of a contractor licensed for that work.

Applicants qualify through completion of a registered apprenticeship program or an equivalent experience-and-training pathway accepted by Connecticut. Supporting documentation may be required to establish classroom education, supervised on-the-job training, apprenticeship completion, or equivalent qualifications.

Applicants with experience, training, or occupational credentials obtained outside Connecticut should follow the applicable state application pathway. Connecticut determines whether the submitted qualifications meet the requirements for examination eligibility and license issuance.

Candidates should review the D-2 scope before applying. Connecticut offers several heating, cooling, refrigeration, piping, fuel, and occupational license classifications, and the selected credential should match the work the applicant intends to perform.

Reference Books

• Included Rental Book: International Mechanical Code, 2021
  This approved mechanical reference covers equipment installation, refrigeration machinery rooms, ventilation, ducts, combustion air, chimneys, vents, piping, and related mechanical requirements. The included copy is highlighted and permanently tabbed.
• Included Rental Book: NFPA 54 - National Fuel Gas Code Handbook, 2012
  This approved fuel-gas reference covers gas piping, sizing, pressure regulation, appliance installation, combustion air, venting, testing, and related safety requirements. The included copy is highlighted and permanently tabbed.
• Included Rental Book: Modern Refrigeration and Air Conditioning, 22nd Edition
  This approved technical reference supports preparation involving refrigeration, air conditioning, warm-air heating, heat pumps, controls, equipment, system operation, maintenance, and troubleshooting. The included copy is highlighted and permanently tabbed.
• Ductulator
  This included tool supports preparation involving duct sizing, airflow, velocity, friction rate, and air-distribution calculations.
• Included Rental Book: HVAC Duct Construction Standards, Metal and Flexible, 2005, 3rd Edition
  This approved reference covers duct materials, reinforcement, fittings, sealing, supports, fabrication, and construction requirements. The included copy is highlighted and permanently tabbed.
• Included Rental Book: NFPA 58 - Liquefied Petroleum Gas Code, 2014
  This approved reference covers LP gas containers, storage, regulators, piping, equipment, installation, separation requirements, and related safety provisions. The included copy is highlighted and permanently tabbed.

The included rental books should be used throughout the six-month course-access period. Repeated use helps candidates learn chapter locations, effective index terms, diagram placement, technical-table organization, and the subjects connected with each permanent tab.

Candidates should protect the rental books during preparation and avoid changes that could damage the references or interfere with exam-room compliance. All rental books must be returned within the rental period in similar condition for the refundable deposit.

Exam Room Approved Books

The following included references and tool are approved for applicable use during the Connecticut D-2 open-book examination:

• International Mechanical Code, 2021
  Use this reference for mechanical equipment, refrigeration machinery rooms, ventilation, ducts, combustion air, chimneys, vents, piping, and installation requirements.
• NFPA 54 - National Fuel Gas Code Handbook, 2012
  Use this reference for natural-gas piping, sizing, appliance installation, regulators, testing, combustion air, and venting.
• Modern Refrigeration and Air Conditioning, 22nd Edition
  Use this reference for refrigeration, heating, air conditioning, heat pumps, controls, equipment, maintenance, and troubleshooting.
• Ductulator
  Use this tool for duct-sizing, airflow, velocity, and friction-rate calculations.
• HVAC Duct Construction Standards, Metal and Flexible, 2005, 3rd Edition
  Use this reference for duct construction, reinforcement, sealing, fittings, materials, and supports.
• NFPA 58 - Liquefied Petroleum Gas Code, 2014
  Use this reference for LP gas containers, regulators, storage, piping, equipment, installation, and safety requirements.

Candidates are responsible for bringing the required references and tools to the examination center. The testing location does not provide each candidate with a complete personal reference set.

All included books arrive highlighted and permanently tabbed. Candidates should inspect the materials before exam day and avoid adding loose notes, temporary tabs, inserted pages, or other items that may conflict with testing-center requirements.

Test Information and Study Materials

A productive D-2 study plan should begin with fuel-gas systems and refrigeration because these are the two largest examination categories. Candidates should practice gas-pipe sizing, table navigation, combustion-air review, venting requirements, refrigeration-cycle principles, component functions, and troubleshooting concepts.

Use NFPA 54 to study natural-gas piping, sizing, pressure, appliance installation, regulators, combustion air, testing, and venting. Practice the longest-length method until the process can be completed accurately under timed conditions.

Use NFPA 58 to review LP gas containers, storage, regulators, piping, equipment, separation requirements, and installation safety. Learn how LP gas topics differ from natural-gas provisions and which reference applies to each system.

Use Modern Refrigeration and Air Conditioning to review refrigerants, compressors, condensers, evaporators, metering devices, heat pumps, furnaces, controls, chillers, pressure-temperature relationships, maintenance, and troubleshooting.

Use the Ductulator and HVAC Duct Construction Standards to study airflow, friction rate, velocity, duct sizing, materials, reinforcement, fittings, sealing, fabrication, and support requirements.

Use the International Mechanical Code for mechanical installation provisions involving equipment, machinery rooms, ventilation, combustion air, ducts, chimneys, vents, and related systems.

The online course provides a structured way to review these topics during 6 months of course access. Candidates can revisit difficult subjects, complete practice-oriented preparation, and use the highlighted and tabbed books to research supporting information.

Timed reference practice should include identifying the likely book before beginning a search. Candidates should use the permanent tabs to reach a major subject and then use the index, chapter headings, definitions, tables, and diagrams to locate the precise information.

Review missed questions carefully. Find the applicable provision or technical explanation, determine why the original selection was incorrect, and study related material that may appear in a differently worded examination question.

How 1 Exam Prep Helps You Reach Your Goal

1 Exam Prep helps Connecticut D-2 candidates prepare with highlighted and tabbed rental references, a Ductulator, and six months of course access in one coordinated package.

Trade-focused study guidance helps candidates review fuel gas, refrigeration, ductwork, heating and cooling principles, heat pumps, furnaces, controls, ventilation, chillers, combustion air, safety, and mechanical requirements in an organized sequence.

Practice-oriented preparation helps candidates connect questions with the correct reference, work through sizing problems, use technical tables, and identify weaker subjects before examination day.

The highlighted and tabbed books provide a practical navigation framework. Highlighting draws attention to useful provisions and technical explanations, while permanent tabs help candidates move between major chapters, definitions, tables, and examination subjects.

Six months of course access gives candidates time to establish a consistent study routine, revisit difficult material, and practice using the same rental references intended for open-book testing.

The package also helps candidates become more comfortable with the examination format. Regular timed study can improve subject recognition, book selection, table navigation, and the ability to move through a broad group of HVAC topics efficiently.

No exam-preparation package can guarantee examination eligibility, a passing score, application approval, or license issuance. Candidates remain responsible for satisfying Connecticut’s training requirements, submitting accurate documentation, preparing thoroughly, and completing all required licensing steps.

FAQ Section

What is included in the D-2 Books & Courses Rental Package?

The package includes five highlighted and tabbed rental books, a Ductulator, and 6 months of course access.

What is the total package price?

The rental cost is $1,890, plus a refundable $750 book deposit. The total package price is $2,640.

How does the refundable book deposit work?

The $750 deposit is refundable when all rental books are returned within the rental period in similar condition.

Are all included books highlighted and tabbed?

Yes. All included books are highlighted and permanently tabbed before delivery.

How long should I allow for the order?

Please allow up to 15 business days for book & course rental package orders.

How long is the course available?

The package includes 6 months of course access.

Is Application Service included?

No. Application Service is not identified as part of this Books & Courses Rental Package.

Is the Connecticut D-2 examination open book?

Yes. Candidates may bring approved references and permitted tools into the examination center under the applicable testing rules.

How many questions are on the D-2 examination?

The examination contains 60 questions. Candidates have two hours to complete the test and must earn a minimum score of 70 percent.

What are the largest D-2 examination categories?

Fuel-gas systems are the largest category with 10 questions. Refrigerants and refrigeration follow with eight questions, and ducts account for six questions.

Is a Ductulator included?

Yes. A Ductulator is included for duct-sizing, airflow, velocity, and friction-rate preparation.

Does the D-2 license allow independent contracting?

No. The D-2 credential is a journeyperson license. The holder performs authorized work while employed by or under the supervision of an appropriately licensed contractor.

Does purchasing this package guarantee a D-2 license?

No. Applicants must meet Connecticut’s qualification requirements, receive examination eligibility, pass the examination, complete the licensing process, and receive state approval.