Connecticut Limited Heating Cooling Journeyperson (D-4) Highlighted & Tabbed Book Package

Prepare for the Connecticut Limited Heating Cooling Journeyperson (D-4) examination with a focused package of approved reference materials that arrive highlighted and tabbed for organized study and open-book exam navigation. This package is designed for refrigeration and cooling professionals who want the primary D-4 references prepared before they begin their final exam review.

The Connecticut D-4 examination covers refrigeration systems used in food storage, air conditioning, and special-process applications. Candidates must understand refrigeration principles, refrigerants, piping and tubing, system components, controls, valves, wiring, testing, inspection, maintenance, troubleshooting, and workplace safety.

The package includes the International Mechanical Code, 2021; Code of Federal Regulations – 29 CFR Part 1926 covering OSHA construction safety; and Modern Refrigeration and Air Conditioning, 22nd Edition. Together, these references support preparation across the major technical, code, and safety subjects associated with the D-4 journeyperson examination.

Every book included in this package is highlighted and permanently tabbed. Important chapters, technical explanations, code provisions, safety topics, tables, definitions, and examination subjects are marked to provide an organized starting point. Candidates can use the prepared references to build a repeatable navigation process before entering the examination room.

Highlighted and tabbed books can help reduce the time spent searching for major topics, but they do not replace studying. Candidates should review every tab, read the highlighted material, understand how each book is organized, and practice finding information under timed conditions. The greatest benefit comes from combining prepared references with consistent technical review.

Field experience is also important. A refrigeration technician may be familiar with installing equipment, measuring operating conditions, replacing components, or tracing control circuits, but the examination may require the candidate to recognize formal terminology or locate a specific requirement in an approved reference.

Studying with the correct books helps connect practical experience with published code language and technical instruction. Candidates can learn which questions belong in the mechanical code, which topics are covered by OSHA regulations, and which technical subjects are addressed in the refrigeration textbook.

This product is a highlighted and tabbed book package. It does not include online course access, application service, rental services, a refundable deposit, or the separate Connecticut contractor Business and Law reference.

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

What You Get

The included books support code review, construction-safety preparation, technical refrigeration study, and open-book reference practice. Candidates should begin using the books as early as possible so the tab locations and highlighted sections become familiar before exam day.

Exam Details

The Connecticut Limited Heating-Cooling Journeyperson (D-4) examination contains 40 questions. Candidates are allowed 1½ hours to complete the examination, and a minimum score of 70 percent is required to pass.

The published D-4 examination outline includes the following subject areas:

• Refrigeration and Refrigerants: 12 questions
• Piping and Tubing: 5 questions
• Components: 7 questions
• Controls, Valves, and Wiring: 7 questions
• Tests, Inspection, and Maintenance: 5 questions
• Safety: 4 questions

Refrigeration and refrigerants make up the largest portion of the examination. Candidates should understand the refrigeration cycle, heat transfer, changes of state, pressure-temperature relationships, refrigerant conditions, and the movement of refrigerant through the compressor, condenser, metering device, and evaporator.

The components category may include compressors, condensers, evaporators, receivers, accumulators, filter-driers, metering devices, motors, fans, and other equipment found in refrigeration and air-conditioning systems. Candidates should understand the purpose of each component and how operating problems can affect the complete system.

Controls, valves, and wiring account for seven questions. Preparation may include thermostats, pressure controls, temperature controls, contactors, relays, capacitors, motors, overload devices, protective controls, service valves, solenoid valves, electrical diagrams, and equipment operating sequences.

Piping and tubing questions may address materials, fittings, joining methods, insulation, supports, routing, pressure considerations, and refrigeration piping practices. Candidates should understand how piping installation can affect refrigerant movement, oil return, system capacity, and reliable equipment operation.

Testing, inspection, and maintenance topics may include leak testing, evacuation, charging, temperature measurements, pressure readings, preventive maintenance, equipment inspection, performance evaluation, system diagnosis, and troubleshooting.

Safety questions may draw from OSHA construction requirements and accepted trade practices. Candidates should review personal protective equipment, electrical hazards, ladders, fall protection, tools, material handling, work areas, and other conditions that may affect refrigeration and cooling work.

With 90 minutes available for 40 questions, candidates have an average of slightly more than two minutes per question. That time must include reading the question, identifying the subject, choosing the correct book, locating the information, and selecting an answer.

Open Book Test

The Connecticut D-4 Limited Heating-Cooling Journeyperson examination is an open-book test. Candidates may bring approved references into the examination center under the current testing rules.

The books in this package are prepared for open-book use with highlighting and permanent tabs. The International Mechanical Code supports code-based refrigeration and mechanical-system questions. OSHA 29 CFR Part 1926 supports construction-safety questions. Modern Refrigeration and Air Conditioning supports technical questions involving refrigeration principles, components, piping, controls, wiring, service, maintenance, and troubleshooting.

Approved references may be highlighted, underlined, annotated, and indexed before the examination. Permanent tabs are permitted. Temporary tabs, removable notes, and loose inserted papers are not allowed.

Candidates may not write in the references during the examination session. Questions and answers may not be written inside the books, and additional sheets may not be attached to or inserted into the approved materials.

The included highlighting directs attention to important material, while permanent tabs identify major subjects and useful locations. Candidates should still review the complete chapter or section surrounding highlighted information because exceptions, notes, definitions, and related requirements may affect the answer.

A practical open-book strategy begins by identifying the type of question. A machinery-room, refrigerant-piping, or mechanical-code question may require the International Mechanical Code. A construction-safety question may lead to OSHA 29 CFR Part 1926. A question involving the refrigeration cycle, system components, wiring, controls, charging, or troubleshooting may require Modern Refrigeration and Air Conditioning.

Candidates should practice using both the tabs and the index. Not every possible examination question can be represented by a single tab. Knowing how to choose useful index terms can help when a subject is not directly marked.

Timed practice is valuable because the D-4 examination allows limited search time. Candidates may benefit from answering familiar questions first, marking difficult questions for later review, and avoiding excessive time on a single item before completing the rest of the test.

Licensing Steps

1. Review the D-4 license scope. Confirm that the Connecticut Limited Cooling Journeyperson classification matches the refrigeration and cooling work you intend to perform.
2. Complete the required training pathway. Applicants must meet Connecticut’s applicable registered apprenticeship or equivalent experience and training requirements.
3. Gather supporting documentation. Prepare apprenticeship records, classroom records, employment information, and other qualification documents required for the application pathway.
4. Complete the journeyperson application. Submit the applicable application and supporting records to the Connecticut Department of Consumer Protection.
5. Receive examination eligibility. The state reviews the application and determines whether the applicant qualifies to take the D-4 examination.
6. Schedule the examination. Follow the current testing provider instructions after eligibility is granted.
7. Study the highlighted and tabbed books. Review the examination outline, read the marked material, and practice using the prepared references under timed conditions.
8. Take the D-4 examination. Complete the 40-question trade test within the 1½-hour testing period.
9. Complete license issuance requirements. Follow the state’s instructions after passing and submit any remaining documents or licensing fees.

Passing the examination does not automatically issue a license. Applicants must complete the applicable experience, training, application, examination, documentation, and licensing requirements established by Connecticut.

State Requirements

The Connecticut D-4 credential is officially identified as the Limited Cooling Journeyperson license. The holder may perform the installation, repair, replacement, maintenance, or alteration of refrigeration systems used in food storage, air conditioning, or special-process systems.

The credential is limited to the work defined by Connecticut for the D-4 classification. Individuals planning to perform heating, fuel gas, oil burner, plumbing, electrical, or other work outside that scope may need an additional occupational license.

The D-4 classification is a journeyperson credential. It does not provide independent contracting authority. A D-4 license holder must perform authorized work while employed by a contractor licensed for the applicable refrigeration and cooling work.

Applicants must complete a registered apprenticeship program or demonstrate equivalent experience and training accepted by the Connecticut Department of Consumer Protection. The state may require records showing classroom instruction, supervised employment, on-the-job training, or apprenticeship completion.

Applicants with experience or education obtained outside Connecticut should follow the state’s procedures for equivalent experience, training, or an equivalent out-of-state license. The Department of Consumer Protection determines whether the submitted qualifications meet the requirements for examination eligibility.

Connecticut offers multiple heating, cooling, piping, refrigeration, sheet metal, and fuel-related licenses. Candidates should review the official scope of work before applying so the selected credential accurately matches their intended duties.

Reference Books

• International Mechanical Code, 2021
  This code addresses mechanical and refrigeration systems, equipment installation, refrigerant piping, machinery rooms, ventilation, testing, system safety, and related mechanical requirements. The included copy is highlighted and tabbed to support organized code study and efficient reference navigation.
• Code of Federal Regulations – 29 CFR Part 1926 (OSHA)
  This federal construction-safety reference covers personal protective equipment, electrical hazards, ladders, scaffolds, fall protection, tools, material handling, excavation, and general jobsite practices. The included copy is highlighted and tabbed for focused safety preparation.
• Modern Refrigeration and Air Conditioning, 22nd Edition
  This comprehensive technical reference covers refrigeration principles, refrigerants, compressors, condensers, evaporators, metering devices, piping, valves, controls, electrical systems, installation, inspection, maintenance, testing, service, and troubleshooting. The included copy is highlighted and tabbed.

Exam Room Approved Books

The following highlighted and tabbed references are included for use during the Connecticut D-4 examination:

• International Mechanical Code, 2021
  Use this code for refrigeration-system requirements, refrigerant piping, machinery rooms, equipment installation, mechanical ventilation, testing, and system-safety provisions.
• Code of Federal Regulations – 29 CFR Part 1926 (OSHA)
  Use this reference for construction-safety questions involving protective equipment, electrical hazards, ladders, fall protection, tools, materials, and jobsite practices.
• Modern Refrigeration and Air Conditioning, 22nd Edition
  Use this reference for refrigeration principles, refrigerants, system components, piping, tubing, controls, valves, wiring, testing, inspection, maintenance, and troubleshooting.

Candidates are responsible for bringing their approved references to the examination center. The testing location does not provide each candidate with a personal set of books.

All three books are highlighted and permanently tabbed before delivery. Candidates should review the markings and tab locations throughout their preparation so the organization becomes familiar before the examination.

Test Information and Study Materials

A productive D-4 study plan should begin with refrigeration and refrigerants because this category contains 12 of the 40 questions. Review the refrigeration cycle, heat transfer, refrigerant states, pressure-temperature relationships, system conditions, and normal equipment operation.

Continue with system components. Learn how compressors, condensers, evaporators, metering devices, receivers, accumulators, filter-driers, motors, and fans contribute to the complete refrigeration system. Study how component problems can affect pressure, temperature, airflow, capacity, and refrigerant movement.

Controls, valves, and wiring should receive focused attention. Candidates should practice recognizing electrical symbols, reading basic wiring diagrams, identifying control functions, and understanding how pressure, temperature, and protective controls affect the operating sequence.

Use the International Mechanical Code to study refrigeration-system requirements, refrigerant piping, equipment installation, machinery rooms, ventilation, testing, and mechanical safety. Review definitions, exceptions, notes, and cross-references instead of reading isolated highlighted sentences.

Use OSHA 29 CFR Part 1926 to review personal protective equipment, electrical hazards, ladders, fall protection, hand and power tools, material handling, and safe construction-site practices.

Use Modern Refrigeration and Air Conditioning to reinforce technical knowledge of refrigerants, system components, piping, controls, electrical systems, charging, evacuation, leak testing, inspection, preventive maintenance, and troubleshooting.

During practice sessions, identify the likely reference before opening a book. Use the permanent tabs to reach major subjects, then use the index and chapter headings to narrow the search. Read the complete supporting material before selecting an answer.

Review incorrect practice answers carefully. Locate the supporting code provision or technical explanation and determine why the selected answer was incorrect. This process can strengthen both technical understanding and book-navigation skill.

How 1 Exam Prep Helps You Reach Your Goal

1 Exam Prep helps Connecticut D-4 candidates begin their preparation with an organized collection of highlighted and tabbed examination references. The package brings the approved mechanical, safety, and refrigeration materials together in one focused set.

Trade-focused review helps candidates connect each examination subject to the appropriate reference. The International Mechanical Code supports code-based refrigeration requirements, OSHA regulations support workplace-safety preparation, and Modern Refrigeration and Air Conditioning reinforces technical refrigeration knowledge.

The included highlighting helps draw attention to useful information, while permanent tabs create a practical navigation system for major topics. Candidates can build familiarity by reviewing the marked material and repeatedly practicing with the books.

Reference-navigation practice can help candidates manage the 1½-hour testing period more effectively. Learning how to identify the correct book, choose an index term, locate a chapter, and read the complete supporting information reduces unnecessary searching.

Practice-oriented preparation also helps candidates identify weak subjects before exam day. Additional review can then be directed toward refrigeration principles, refrigerants, piping, components, controls, wiring, maintenance, or OSHA safety.

No book package can guarantee a passing result, examination eligibility, application approval, or license issuance. Consistent study, qualifying trade experience, familiarity with the references, and effective time management remain important parts of the Connecticut D-4 licensing process.

FAQ Section

What books are included in this package?

The package includes the International Mechanical Code, 2021; Code of Federal Regulations – 29 CFR Part 1926 (OSHA); and Modern Refrigeration and Air Conditioning, 22nd Edition.

Are all included books highlighted and tabbed?

Yes. Every book in the package is highlighted and permanently tabbed before delivery.

How long should I allow for my order?

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

Is the Connecticut D-4 examination open book?

Yes. The Connecticut D-4 examination is open book, and candidates may bring approved references into the examination center under the current testing rules.

How many questions are on the D-4 examination?

The examination contains 40 questions. Candidates have 1½ hours to complete the test and must earn a minimum score of 70 percent.

What is the largest examination category?

Refrigeration and refrigerants are the largest category, accounting for 12 questions. Components and controls, valves, and wiring each account for seven questions.

Does this package include an online course?

No. This product contains highlighted and tabbed books only. Online course access is not included.

Is this a rental package?

No. This product is a highlighted and tabbed book package and is not identified as a rental package.

Does the package include application assistance?

No application service is listed as part of this highlighted and tabbed book package.

Does the D-4 license allow independent contracting?

No. The D-4 credential is a journeyperson license. The license holder must perform authorized work while employed by an appropriately licensed contractor.

Does purchasing this package guarantee a passing score?

No. Examination performance depends on the candidate’s experience, technical knowledge, preparation, reference-navigation skills, time management, and performance on test day.