What Is the South Carolina Air Conditioning Classification?

South Carolina regulates commercial air-conditioning work through its Contractor's Licensing Board as a Mechanical Contractor classification.

The classification abbreviation is AC.

Typical work can include:

• Commercial air-conditioning systems.
• Heating systems that produce conditioned air.
• Heat pumps.
• Furnaces.
• Mechanical ventilation.
• Duct systems.
• Exhaust systems.
• Mechanical piping associated with HVAC systems.
• HVAC controls.
• Air-distribution systems.
• Refrigeration systems.
• Packaged HVAC equipment.

The Board's current classification guide says that AC includes PK, Packaged Equipment, and RG, Refrigeration.

Review the South Carolina Contractor's Licensing Board information before choosing your classification.

What Does the AC Classification Not Cover?

The official PSI scope contains an important limitation.

Hot-water and steam-heating systems and their components are not included under the Air Conditioning classification.

South Carolina separately regulates mechanical classifications such as:

• Heating.
• Plumbing.
• Pressure and Process Piping.
• Electrical.
• Lightning Protection.

Make sure the AC classification covers all the work your company intends to offer. The best time to discover that you need another classification is before signing the contract.

When Is a South Carolina Commercial HVAC License Required?

South Carolina generally requires a General or Mechanical Contractor license for regulated commercial construction when the total cost of the regulated work is greater than $10,000.

This can include offering to perform, supervising, or actually performing regulated mechanical construction.

Air-conditioning work can fall under this requirement when the commercial HVAC portion of the project crosses the threshold.

A license issued by the Contractor's Licensing Board can allow the licensed entity to perform both commercial and residential construction within its authorized classification and group limit.

Step 1: Get the Required Commercial HVAC Experience

South Carolina requires applicants seeking general or mechanical contractor classifications by examination to document at least two years of relevant work experience performed within the previous five years.

For the AC classification, that experience should be connected to air-conditioning and mechanical work.

Useful experience may include:

• Commercial HVAC installation.
• Air-conditioning equipment replacement.
• Duct fabrication and installation.
• Load calculations.
• Airflow and duct sizing.
• Heat pumps.
• Furnaces.
• Refrigeration systems.
• Fuel-gas systems.
• HVAC piping.
• Controls.
• Testing, adjusting, and balancing.
• Mechanical code compliance.
• Commercial project supervision.

South Carolina uses a Work Experience Affidavit as part of the licensing process. Be specific about the kind of equipment and systems you worked on.

"I did HVAC stuff" may be wonderfully short, but it is not much of a work-history explanation.

Step 2: Understand the Primary Qualifying Party

South Carolina uses the term Primary Qualifying Party, or PQP.

The PQP is the individual designated as the principal person responsible for directing or reviewing the work performed under a specific classification.

A company applying for the Air Conditioning classification must have a properly qualified PQP for that classification.

Additional Qualifying Parties may also be certified, but the PQP is the person formally designated as the primary qualifier for the classification.

The PQP must satisfy the required examination or accepted waiver route before the business applies for licensure.

Step 3: Schedule the Air Conditioning Exam Through PSI

South Carolina currently uses PSI to administer its commercial contractor examinations.

There is currently no Board preapproval required before scheduling the normal PSI commercial contractor exams.

The technical examination you want is:

Register through the PSI South Carolina Commercial Contractor testing portal.

Be careful not to accidentally choose Packaged Equipment, Refrigeration, or Heating if the broader Air Conditioning classification is your goal.

Step 4: Understand the Current Air Conditioning Exam

The current PSI Candidate Information Bulletin lists:

• 80 scored questions.
• 4-hour time limit.
• 56 correct answers required.
• 70% passing score.
• $60 examination fee.
• Open-book format.

PSI may also include a small number of experimental questions. These are not scored, but they can still use some of your examination time.

Four hours for 80 scored questions gives you a healthy amount of time compared with some contractor exams, but it is still smart to know your books.

Open book does not mean "bring eight books and hope one whispers the answer."

Step 5: Know What Is on the Air Conditioning Exam

The South Carolina Air Conditioning examination is broad. It contains 41 listed content areas.

Load Calculations is the largest individual content area at seven questions, but the duct-related categories together account for a much larger share of the exam.

Step 6: Get the Current Exam References

The current PSI reference list includes:

• 2021 International Mechanical Code with South Carolina modifications, or the 2018 South Carolina Mechanical Code.
• 2021 International Fuel Gas Code with South Carolina modifications, or the 2018 South Carolina Fuel Gas Code.
• 29 CFR Part 1926 OSHA Construction Regulations with current applicable amendments.
• Manual N, Commercial Load Calculation for Small Commercial Buildings, 5th Edition.
• Manual D, Residential Duct Systems, 3rd Edition.
• Manual J, Residential Load Calculations, Eighth Full Edition.
• ACCA Ductulator.
• Modern Refrigeration and Air Conditioning, 21st or 22nd Edition.

PSI states that later editions of non-code references may generally be used, but code questions are based on the specific code editions listed for the exam.

For a complete set, review the South Carolina Commercial Air Conditioning Contractor Exam Book Package.

Step 7: Prepare Your Open-Book References Correctly

South Carolina's commercial contractor examinations are open book, but PSI has strict rules for the references.

Current PSI rules allow:

• Highlighting.
• Underlining.
• Indexing.
• Permanent tabs.
• Approved reference books listed in the bulletin.

Current rules do not allow:

• Handwritten notes in the books.
• Loose additional papers.
• Attached extra pages.
• Temporary tabs.
• Post-it notes.
• Tabs that can be removed without tearing the page.

PSI inspects books before and after the examination.

For prepared references, review the South Carolina Commercial Air Conditioning Highlighted & Tabbed Book Package.

Step 8: Focus Heavily on Load Calculations

Load calculations are the largest single named exam category with seven questions.

Practice working with:

• Commercial building cooling loads.
• Heating loads.
• Outdoor design conditions.
• Windows and doors.
• Wall and roof construction.
• Occupancy.
• Internal heat gains.
• Ventilation loads.
• Equipment sizing.

Manual N is particularly important for commercial load calculations.

Learn the process instead of trying to memorize random numbers. HVAC equipment has enough numbers already.

Step 9: Learn Duct Design and Air Distribution

Ductwork is spread across several exam categories, making it one of the biggest overall study areas.

Review:

• Airflow.
• Static pressure.
• Friction rate.
• Duct sizing.
• Equivalent duct sizes.
• Metal duct systems.
• Fiberglass duct systems.
• Duct fittings.
• Supply and return systems.
• Exhaust systems.
• Filters.
• Ventilation equipment.

Practice using the ACCA Ductulator until reading it feels normal.

Test day is not the ideal moment to stare at a duct calculator like it arrived from another planet.

Step 10: Study Heat Pumps, Furnaces, and HVAC Equipment

The exam includes questions on heat pumps, furnaces, specialized heating equipment, air-conditioning systems, and related equipment.

Study:

• Heat-pump operation.
• Heating and cooling cycles.
• Furnace operation.
• Equipment installation.
• Clearances.
• Airflow requirements.
• Equipment selection.
• System components.

Remember that the AC classification does not include hot-water or steam-heating systems.

Step 11: Study Fuel Gas and Combustion Air

Fuel-fired HVAC equipment brings fuel-gas rules into the exam.

Review:

• Natural gas.
• LP gas.
• Gas piping.
• Pipe sizing.
• Combustion air.
• Chimneys.
• Flues.
• Vents.
• Vent connectors.
• Appliance installation.

Learn the layout of the Fuel Gas Code so you can move quickly between sizing, combustion-air, and venting requirements.

Step 12: Study Refrigeration

South Carolina's classification guide states that AC includes the Refrigeration classification.

That makes refrigeration knowledge valuable both for the exam and for actual licensed work.

Review:

• The refrigeration cycle.
• Compressors.
• Evaporators.
• Condensers.
• Metering devices.
• Refrigerant properties.
• Pressure-temperature relationships.
• System charging.
• Refrigeration controls.
• Service and troubleshooting concepts.

Step 13: Remember EPA Section 608

Your South Carolina contractor license and federal refrigerant certification are separate things.

Technicians who maintain, service, repair, or dispose of covered air-conditioning and refrigeration equipment in a way that could release regulated refrigerants generally need the appropriate EPA Section 608 Technician Certification.

Certification types include:

• Type I.
• Type II.
• Type III.
• Universal.

Review the EPA Section 608 Technician Certification requirements if your work involves refrigerants.

Step 14: Use Timed Practice

A strong exam-prep plan should combine technical knowledge with fast book navigation.

1. Study one HVAC topic at a time.
2. Answer practice questions without rushing.
3. Look up every missed answer.
4. Identify which reference contains the answer.
5. Practice finding that section again.
6. Mix mechanical-code, fuel-gas, load, duct, and refrigeration questions.
7. Use the Ductulator during practice.
8. Complete full 80-question timed practice sessions.

For structured study, review the South Carolina Commercial Air Conditioning Contractor Online Exam Prep Course.

Candidates who prefer instructor support can also review South Carolina Air Conditioning Live Virtual + Self Study Training.

Step 15: Pass South Carolina Business Management and Law

Air Conditioning applicants also need the South Carolina Business Management and Law for Commercial Contractors examination.

The current PSI bulletin lists:

• 50 questions.
• 35 correct answers required.
• 70% passing score.
• 125 minutes.
• $75 examination fee.
• Open-book format.

Subjects include:

• Business Management.
• Estimating and Bidding.
• Contracts and Agreements.
• Project Management.
• Insurance and Bonding.
• Safety Recordkeeping.
• Labor Laws.
• Financial Management.
• Tax Laws.
• Liens.
• Environmental Laws and Regulations.

The current reference is the NASCLA Contractors Guide to Business, Law and Project Management, South Carolina Commercial Contractors, 9th Edition.

You can review the South Carolina Commercial Business and Law Online Course and the South Carolina NASCLA Business and Law 9th Edition.

Step 16: Understand South Carolina's Retesting Rules

Technical examinations have stricter retesting rules than Business Management and Law.

For the Air Conditioning technical exam, a candidate may currently take the same classification exam two times within a 12-month period. After that, another attempt is generally allowed only once every six months.

Business Management and Law may currently be taken on an unlimited basis during a 12-month period.

That makes your first two Air Conditioning attempts worth treating seriously.

Step 17: Choose Your Mechanical Contractor Group

Passing the trade exam determines the classification you can qualify.

Your license group determines how large a job or bid the licensed business can undertake.

Step 18: Choose a Financial Statement or Surety Bond

South Carolina requires financial qualification for the mechanical contractor license.

For an initial application:

• Groups 1 and 2: an owner-prepared financial statement with the required affidavit may be used, or the proper surety bond.
• Groups 3 and 4: a financial statement compiled by a licensed CPA in accordance with GAAP may be used, or the proper surety bond.
• Group 5: an audited balance sheet prepared by a licensed CPA in accordance with GAAP may be used, or the $300,000 mechanical contractor surety bond.

The balance sheet must generally be dated no more than 12 months before the application.

Review South Carolina's current financial and license-group requirements before preparing your application.

Step 19: Register the Business

The contractor license is issued to the business entity.

Depending on your structure, that may be:

• A sole proprietorship.
• A partnership.
• An LLC.
• A corporation.
• Another entity recognized by South Carolina.

Companies other than sole proprietorships generally need verification showing authority to conduct business in South Carolina from the Secretary of State.

Keep the legal business name consistent throughout the application.

An extra comma in an LLC name should not be allowed to become the hardest part of HVAC licensing.

Step 20: Submit the Contractor License Application

Once the examinations and PQP requirements are complete, submit the General and Mechanical Contractor application to the South Carolina Contractor's Licensing Board.

The current initial license fee is $350.

A typical Air Conditioning application package includes:

• General and Mechanical Contractor Initial Application, Doc. 165.
• Primary Qualifying Party documentation, Doc. 168 when applicable.
• Air Conditioning technical exam passing score.
• Business Management and Law passing score.
• Work Experience Affidavit.
• At least two years of qualifying experience within the previous five years.
• Secretary of State documentation when applicable.
• Financial statement or qualifying mechanical contractor surety bond.
• The current $350 license fee.
• Any additional disclosures required by the application.

You can find current forms on the South Carolina Contractor's Licensing Board Applications and Forms page.

Do Not Exceed Your Group Limit

The classification and financial group work together.

For example:

• An AC1 license is limited to $35,000 per bid and job.
• An AC2 license is limited to $100,000.
• An AC3 license is limited to $200,000.
• An AC4 license is limited to $400,000.
• An AC5 license is Unlimited.

Do not bid or contract beyond the financial group shown on your license.

Passing the same AC exam does not mean every company receives the same project limit.

Does South Carolina Offer Reciprocity?

South Carolina has technical exam waiver agreements with several states and programs.

Current Air Conditioning or related waiver paths may include qualifying examinations from jurisdictions such as:

• Alabama.
• Georgia.
• Louisiana.
• North Carolina.
• Tennessee.
• Texas.
• Utah for qualifying older exams.
• Carolinas AGC mechanical trades certification.

The exact license, examination, date, and classification matter.

Review the current South Carolina waiver and qualifying-party information before assuming an out-of-state license qualifies.

What About the Carolinas AGC Mechanical Certification?

South Carolina changed its mechanical trades certification provider beginning January 1, 2026.

Current Board guidance recognizes qualifying HARV Master Mechanical certifications previously issued by the Municipal Association of South Carolina and current qualifying certifications issued through Carolinas AGC.

A qualifying Master Mechanical certification can correspond to South Carolina Air Conditioning and Heating classifications.

Candidates using this route still need to complete the remaining Contractor's Licensing Board requirements.

Local Licenses and Permits Still Matter

Your state mechanical contractor license is only one part of operating an HVAC company.

Cities and counties may separately require:

• Business licenses.
• Contractor registration.
• Mechanical permits.
• Inspections.
• Local fees.
• Project-specific documentation.

Check the city or county where each project is located.

A state license opens a lot of doors. It does not magically cause the local permit counter to vanish.

How Long Is the South Carolina Mechanical Contractor License Valid?

South Carolina Mechanical Contractor licenses expire on October 31 of odd-numbered years.

The current biennial renewal fee is $135.

Renewal requires current financial documentation or an acceptable surety bond or continuation certificate supporting the license group.

Current late fees are:

• November: $100 late fee plus the renewal fee.
• December: $150 late fee plus the renewal fee.
• January: $200 late fee plus the renewal fee.

After January 31 following the expiration date, the license lapses and must go through the applicable reinstatement process.

Mechanical contractor renewals for the 2027-2029 cycle are currently scheduled to open in August 2027.

South Carolina Commercial Air Conditioning Exam Prep Resources

A Simple South Carolina Air Conditioning Licensing Roadmap

1. Confirm the AC classification matches the HVAC work your business will perform.
2. Build at least two years of relevant experience within the previous five years.
3. Choose the business entity that will hold the license.
4. Identify the Primary Qualifying Party.
5. Register for the Air Conditioning examination through PSI.
6. Get the current approved reference books.
7. Highlight and permanently tab the books according to PSI rules.
8. Study load calculations, duct systems, HVAC equipment, fuel gas, refrigeration, piping, and controls.
9. Practice completing 80 questions within four hours.
10. Pass the Air Conditioning exam with at least 70%.
11. Pass South Carolina Business Management and Law with at least 70%.
12. Document the required commercial work experience.
13. Select the appropriate mechanical license group.
14. Prepare the required financial statement or surety bond.
15. Complete Secretary of State registration when applicable.
16. Complete the PQP documentation.
17. Submit the contractor application and current $350 fee.
18. Wait for license issuance before performing regulated work as a licensed contractor.
19. Stay within the AC classification and financial group shown on the license.
20. Maintain local permits, business licenses, financial qualification, and biennial renewal requirements.

Helpful South Carolina Licensing Resources

Frequently Asked Questions

Here are common questions about becoming a South Carolina Commercial Air Conditioning Contractor.

Key Takeaways

• South Carolina's Commercial Air Conditioning classification is AC. The Board's classification guide also states that AC includes Packaged Equipment and Refrigeration.
• Commercial mechanical licensing generally applies when regulated work is over $10,000. Applicants by examination need at least two years of relevant experience within the previous five years.
• The current Air Conditioning exam has 80 questions and allows four hours. You need 70% to pass, the exam currently costs $60, and it is open book.
• Business Management and Law is required too. That exam currently has 50 questions, allows 125 minutes, costs $75, and requires 70%.
• Your financial group controls project size. South Carolina mechanical contractor limits range from $35,000 for Group 1 to Unlimited for Group 5.

Final Thoughts Before You Start

Becoming a South Carolina Commercial Air Conditioning Contractor is about more than knowing how to make a building cold in July.

The AC classification covers a broad range of mechanical work involving conditioned air, HVAC equipment, duct systems, heat pumps, furnaces, controls, fuel gas, refrigeration, airflow, and related systems. The Board also includes Packaged Equipment and Refrigeration under the AC classification.

Start with your experience. South Carolina expects applicants by examination to document at least two years of relevant experience within the previous five years. Make sure your work history clearly shows the commercial HVAC systems you have installed, repaired, supervised, or serviced.

Next, get serious about the exams.

The technical test has 80 scored questions and gives you four hours. Load calculations are important, but ductwork is spread across many different categories and makes up a large part of the overall examination. Fuel gas, heat pumps, refrigeration, controls, piping, and equipment also deserve plenty of study time.

Learn your books before test day. PSI allows approved books, highlighting, and permanent tabs, but the references must follow the exam-room rules. Organizing them correctly can save valuable time.

Do not overlook Business Management and Law. A contractor can understand compressors, airflow, and refrigerant pressures perfectly and still lose money because a contract, bid, tax issue, lien, or financial decision went sideways.

After the exams, focus on the business license itself. South Carolina requires a Primary Qualifying Party, experience documentation, proper business registration, and financial qualification.

The financial group is especially important. A Group 1 contractor and a Group 5 contractor may hold the same AC classification, but they do not have the same bid and job limit. Choose a group that fits the size of projects your company expects to pursue and make sure your financial statement or surety bond supports it.

If you work with regulated refrigerants, remember that the South Carolina contractor license does not replace EPA Section 608 technician certification. Federal refrigerant rules still apply to covered work.

Finally, remember that local requirements remain part of the job. Cities and counties may require business licenses, mechanical permits, contractor registration, inspections, or other paperwork.

When you are ready to prepare, explore the South Carolina Commercial Air Conditioning Contractor exam prep resources from 1 Exam Prep. Strong commercial HVAC experience, organized open-book references, timed practice, and a clear understanding of South Carolina's PQP and financial-group system can make the licensing process much easier to manage.