Arizona Boilers, Including Solar Residential Contractor (R-4) Highlighted & Tabbed Book Package

The Arizona Boilers, Including Solar Residential Contractor (R-4) Highlighted & Tabbed Book Package is designed for contractors preparing for the Arizona R-4 Boilers, Including Solar Residential trade examination pathway. This package brings together the boiler, mechanical, fuel gas, OSHA, and solar references used to support organized preparation for Arizona’s residential boiler contractor licensing process with solar-related work included.

The R-4 classification is connected to residential steam and hot water boiler work, including solar. Candidates preparing for this exam should be ready to study boiler systems, steam and hot water piping, gas piping, burners, controls, flues, vents, sizing, estimating, testing, inspection, OSHA safety, fuel gas requirements, mechanical code provisions, and solar water or pool heating concepts. Because this license includes a solar component, preparation should include both the core boiler exam and the solar-specific exam.

This highlighted and tabbed book package is built to make the study process more organized. Large technical references can be difficult to use without a clear system. Highlighted sections help guide review toward important material, while permanent tabs help candidates move through major topics, code sections, tables, definitions, safety rules, and technical reference areas more efficiently. For an open book contractor exam, strong reference navigation can make study sessions more productive and help candidates work through questions with greater confidence.

This package is a strong fit for residential boiler contractors, hydronic heating professionals, solar water heating contractors, HVAC technicians, mechanical contractors, fuel gas installers, qualifying parties, business owners, and tradespeople preparing for the Arizona R-4 Boilers, Including Solar Residential Contractor license. It is especially useful for candidates who have hands-on experience but need organized references for exam-focused study and open book test preparation.

What You Get

• Highlighted reference books: Key areas are highlighted to help candidates focus on important exam-related material during preparation.
• Permanent tabs: Tabs are placed to support faster movement through major topics, code sections, tables, definitions, and reference areas.
• Residential boiler study support: The package supports review across boilers, steam and hot water piping, gas piping, burners, controls, flues, vents, sizing, estimating, testing, inspection, mechanical code, fuel gas code, and OSHA safety.
• Solar preparation support: The package includes a solar reference connected to solar water heating, pool heating, collection loops, system components, installation, mounting, maintenance, system principles, and solar piping.
• Organized exam preparation structure: The books are prepared to help reduce search time, improve reference familiarity, and support more focused study sessions.

Exam Details

The Arizona R-4 Boilers, Including Solar Residential examination pathway is administered through PSI for the Arizona Registrar of Contractors. The R-4 pathway includes a core boiler examination and a solar-specific examination.

The R-4 Boilers examination contains 50 questions. The minimum passing score is 70%, and the time allowed is 120 minutes. The R-4 Solar examination contains 30 questions. The minimum passing score is 70%, and the time allowed is 75 minutes.

The content outline for the R-4 Boilers examination includes:

• Boilers: 12 items
• Steam and Hot Water Piping: 8 items
• Gas Piping: 8 items
• Burners: 5 items
• Controls: 5 items
• Flues and Vents: 4 items
• Sizing and Estimating: 4 items
• Testing and Inspection: 4 items

The content outline for the R-4 Solar examination includes:

• Collection Loops: 5 items
• Components: 4 items
• Installation: 5 items
• Maintenance: 2 items
• Mounting: 4 items
• Principles: 5 items
• Solar Systems Piping: 5 items

The examination may include questions based on listed reference materials, trade knowledge, and general industry practices. Code questions are based on the specific code editions listed for the examination. Candidates should prepare with the correct code editions and become familiar with where major subjects, tables, definitions, formulas, installation rules, safety provisions, and inspection requirements are located before test day.

Open Book Test

The Arizona R-4 Boilers, Including Solar Residential trade examination pathway is open book using approved reference materials. Candidates are responsible for bringing their own approved references to the examination center.

The approved exam-room references listed for the R-4 Boilers examination include Code of Federal Regulations - 29 CFR Part 1926 (OSHA), International Mechanical Code, 2018, and International Fuel Gas Code, 2018. These approved references may be highlighted, underlined, annotated, and indexed before the examination session.

Candidates may not write, highlight, underline, or index references during the exam. Additional papers, whether loose or attached, are not permitted with approved references. References may be tabbed or indexed with permanent tabs only. Permanent tabs are tabs that would tear the page if removed. Temporary tabs, removable sticky tabs, and loose papers are not permitted in the examination center.

Low Pressure Boilers 5th Edition is included in this package as a study reference connected to boiler operation, steam systems, hot water systems, boiler controls, safety devices, fuel systems, and maintenance concepts. Solar Water and Pool Heating Design and Installation Manual is included as a study reference for the solar exam content. These study references are useful for building technical knowledge, but they are not listed as exam-room-approved references for the R-4 examination pathway.

Candidates may use a silent, nonprinting, non-programmable calculator in the examination center. Downloaded references may be brought into the testing center only when bound, such as spiral-bound or placed in a binder after being hole-punched.

Licensing Steps

Arizona contractor licensing is handled by the Arizona Registrar of Contractors. Applicants should begin by identifying the correct license classification and reviewing the examination requirements tied to that classification. The person completing the required examination process must serve as the qualifying party for the license.

The R-4 classification is the residential boilers, including solar, contractor classification. Candidates pursuing this license should prepare for residential boiler systems, steam and hot water heating, gas piping, mechanical code requirements, fuel gas code requirements, boiler controls, combustion equipment, flues, vents, sizing, estimating, testing, inspection, and solar water or pool heating concepts.

For many new Arizona contractor license applicants, the licensing process also includes the Arizona Statutes and Rules Exam, also known as the SRE. The SRE is separate from the trade examination. The R-4 trade exam focuses on residential boiler and solar trade knowledge, while the statutes and rules requirement covers Arizona contractor law, rules, and regulatory responsibilities.

After the required examinations are completed, the applicant submits the completed contractor license application and supporting documentation to the Arizona Registrar of Contractors. Examination requirements must be completed before the application can be accepted for processing. Score reports must be submitted within the required period after passing the examination.

A practical licensing path includes confirming the R-4 classification, studying the approved trade references, learning the open book testing rules, completing the Arizona statutes and rules requirement when applicable, scheduling and taking the required PSI examinations, and submitting the completed license application package to the Arizona Registrar of Contractors.

State Requirements

The Arizona R-4 Boilers, Including Solar Residential classification is tied to installation and repair of steam and hot water boilers. When necessary, a new circuit may be added to the existing service panel or sub-panel. Installation of a new service panel or sub-panel is excluded.

This scope includes the R-4R subclassification, which is focused on residential boiler work. The R-4 classification adds the solar component, so candidates should prepare for both boiler system knowledge and solar water or pool heating concepts. Candidates should keep this classification boundary in mind while studying and avoid confusing the R-4 scope with broader electrical, plumbing, or unrelated mechanical classifications.

The trade exam content reflects the practical and technical knowledge needed for residential boiler work. Candidates should be prepared for questions involving boiler systems, steam piping, hot water piping, fuel gas piping, burners, combustion, boiler controls, safety devices, flues, vents, sizing, estimating, testing, and inspection. The solar portion adds questions involving collection loops, components, installation, maintenance, mounting, principles, and solar systems piping.

Arizona licensing involves more than passing the trade examinations. Applicants may also need to satisfy business, entity, bonding, experience, background, application, and qualifying party requirements depending on the applicant’s structure and license type. The trade exams are major steps in the process, but the license is issued only after the Arizona Registrar of Contractors reviews and processes the completed application.

Reference Books

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

• Code of Federal Regulations - 29 CFR Part 1926 (OSHA)
  This construction safety reference supports OSHA-related exam content and covers federal construction standards used to address jobsite hazards, worker protection, safe work practices, and construction safety requirements.
• International Mechanical Code, 2018
  This mechanical code reference supports questions involving mechanical equipment, heating systems, boilers, hydronic piping, ventilation, combustion air, flues, vents, installation requirements, and inspection-related provisions.
• International Fuel Gas Code, 2018
  This fuel gas code reference supports questions involving gas piping systems, combustion air, appliance installation, venting, inspection, testing, shutoff requirements, sizing, and fuel gas safety provisions.
• Low Pressure Boilers 5th Edition
  This boiler reference supports study of low-pressure boiler operation, steam systems, hot water systems, burners, controls, safety devices, fuel systems, maintenance, inspection, and boiler operating principles.
• Solar Water and Pool Heating Design and Installation Manual
  This solar reference supports preparation for solar water heating and pool heating topics, including collection loops, solar components, system principles, installation, mounting, maintenance, and solar system piping.

Test Information and Study Materials

The Arizona R-4 exam pathway rewards candidates who combine residential boiler experience, solar system knowledge, and organized reference use. Since the boiler exam contains 50 questions and the solar exam contains 30 questions, candidates should practice using the approved references and study materials before exam day. The goal is not to read long sections during the test. The goal is to know which book to use, where the topic is located, and how to confirm the answer efficiently.

The boiler category is the largest subject area on the core exam. Candidates should study boiler types, system components, boiler operation, combustion basics, steam systems, hot water systems, safety controls, pressure and temperature control, equipment installation, maintenance concepts, and operating principles. Low Pressure Boilers 5th Edition is especially useful for building this technical foundation during study.

The steam and hot water piping category supports questions involving piping systems, hydronic circulation, steam distribution, condensate return, valves, fittings, system layout, pipe sizing concepts, insulation, pressure considerations, and related installation practices. Candidates should understand how boiler piping supports safe and efficient residential heating system operation.

The gas piping category connects closely to the International Fuel Gas Code. Candidates should practice locating gas pipe sizing tables, appliance connection requirements, shutoff provisions, combustion air rules, pressure testing provisions, inspection requirements, venting rules, and safety-related fuel gas provisions. Fuel gas questions often require candidates to use a table or code section rather than rely only on field experience.

The burners and controls categories require candidates to understand how boilers operate safely. Study should include burners, ignition, combustion, flame supervision, operating controls, limit controls, pressure controls, temperature controls, safety valves, low-water protection, and related boiler safety devices. These subjects connect practical boiler knowledge with the written terminology used in exam questions.

The flues and vents category should be studied through both trade knowledge and code navigation. Candidates should understand venting principles, draft, combustion products, vent connectors, clearances, termination requirements, and appliance venting rules. The International Mechanical Code and International Fuel Gas Code both support this area of preparation.

The solar portion should be studied as its own exam section. Candidates should review collection loops, solar system components, mounting methods, installation practices, maintenance needs, solar system principles, and solar system piping. Solar Water and Pool Heating Design and Installation Manual supports this preparation by helping candidates understand how solar water and pool heating systems are designed, assembled, operated, and maintained.

The OSHA reference should be reviewed for construction safety rules that apply to residential boiler and solar-related work. Safety questions may involve personal protective equipment, ladders, scaffolds, electrical hazards, material handling, hazard communication, tools, fall protection, and general jobsite safety. Candidates should become familiar with the structure of the OSHA reference so safety information can be located quickly.

A practical study method is to work through the content outline one subject at a time. Start with boilers, steam and hot water piping, and gas piping because they represent the largest portions of the core exam. Then move into burners, controls, flues and vents, sizing and estimating, testing and inspection, and the full solar content outline. During each study session, candidates should practice using the highlighted and tabbed books under timed conditions.

How 1 Exam Prep Helps You Reach Your Goal

1 Exam Prep helps contractor candidates prepare with organized study materials, trade-focused review, and reference navigation support. This highlighted and tabbed book package is designed to help Arizona R-4 candidates study the approved code references and supporting boiler and solar study materials with a clearer structure.

For many candidates, the challenge is not only learning residential boiler systems or solar heating concepts. The challenge is knowing where to find information quickly inside large technical references. 1 Exam Prep helps simplify that process by preparing books with highlights and tabs that support focused review and faster navigation.

The highlighted sections help direct attention to important material, while the tabs make it easier to move between major subjects during study sessions. Candidates can use the package to review boilers, steam and hot water piping, gas piping, burners, controls, flues, vents, sizing, estimating, testing, inspection, fuel gas code, mechanical code, OSHA safety, solar components, solar piping, mounting, installation, and maintenance in a more organized way.

1 Exam Prep’s approach is practical and exam-focused. The goal is to help candidates study with less confusion, use their references more effectively, and build confidence through consistent preparation. No book package can guarantee a passing score or license approval, but organized references can make the preparation process clearer, more efficient, and easier to manage.

FAQ Section

Is the Arizona R-4 Boilers, Including Solar Residential exam open book?

Yes. The Arizona R-4 exam pathway is open book using approved reference materials. Candidates must bring their own approved references and follow the testing center rules for highlighting, annotations, indexing, and tabs.

How many questions are on the Arizona R-4 exam pathway?

The R-4 Boilers examination contains 50 questions and allows 120 minutes. The R-4 Solar examination contains 30 questions and allows 75 minutes. Each examination requires a minimum passing score of 70%.

What topics are covered on the R-4 Boilers exam?

The core exam covers boilers, steam and hot water piping, gas piping, burners, controls, flues and vents, sizing and estimating, and testing and inspection.

What topics are covered on the R-4 Solar exam?

The solar exam covers collection loops, components, installation, maintenance, mounting, principles, and solar systems piping.

Which books are allowed in the examination center?

The approved exam-room references listed for the R-4 Boilers examination include Code of Federal Regulations - 29 CFR Part 1926 (OSHA), International Mechanical Code, 2018, and International Fuel Gas Code, 2018.

Are Low Pressure Boilers and the solar manual allowed in the exam room?

No. Low Pressure Boilers 5th Edition and Solar Water and Pool Heating Design and Installation Manual are included as study references, but they are not listed as exam-room-approved references for the R-4 examination pathway.

Can I write in my books during the exam?

No. References may be highlighted, underlined, annotated, and indexed before the exam, but candidates may not write, highlight, underline, or index references during the examination session.

Are removable tabs allowed?

No. Tabs must be permanent. Permanent tabs are tabs that would tear the page if removed. Temporary sticky tabs and removable tabs are not permitted.

What work does the Arizona R-4 classification cover?

The R-4 residential boilers, including solar, classification is tied to installation and repair of steam and hot water boilers. When necessary, a new circuit may be added to an existing service panel or sub-panel, but installation of a new service panel or sub-panel is excluded.

Who administers the Arizona R-4 trade exams?

The Arizona Registrar of Contractors has contracted with PSI to conduct the trade examination program for Arizona contractor licensing.

Is this package helpful for experienced boiler and solar heating contractors?

Yes. Field experience is valuable, but the exams also require candidates to use code books and technical references efficiently. Highlighted and tabbed books help experienced tradespeople connect practical knowledge with the references used for preparation.