South Carolina HVAC Experience Requirements

How Much Experience You Need

The minimum experience varies by track:

Residential (RBC): One year of hands-on residential HVAC experience within the past five years, performed under the direct supervision of a licensed builder or licensed HVAC contractor.

Commercial (CLB): Two years of primarily commercial mechanical experience within the past five years in the specific subclassification you're applying for (Air Conditioning, Heating, Packaged Equipment, or Refrigeration).

The "past five years" window is strict. If your qualifying experience is older than five years, it doesn't count regardless of how extensive it was. This trips up technicians who took a break from the trade or switched industries — if you've been out of HVAC work for three years, you may need to work under a licensed contractor again to accumulate fresh, qualifying hours.

An alternative exists for the commercial track: completion of a four-year apprenticeship through the PHCC (Plumbing, Heating, and Cooling Contractors Association) Academy of North Carolina satisfies the CLB's experience requirement in lieu of the standard two-year commercial threshold.

The Experience Affidavit

Both boards require a formal affidavit verifying your work experience. For commercial applications, this is Document 167 — the Work Experience Affidavit filed with the CLB. For residential applications, it's the Residential HVAC Installer and Repairer Experience Affidavit submitted through the RBC's online portal.

The affidavit must be completed and signed by the supervising licensee who directly oversaw your work. This is the person who held the license under which you performed HVAC tasks — your employer, a licensed foreman, or the company's qualifying party.

The critical section is the description of work. The board wants your personal, hands-on activities — not the company's project portfolio. Specific examples that work:

• "Installed 3-ton and 5-ton split-system heat pumps including refrigerant line sets, condensate drain routing, and electrical hookups for residential change-outs"
• "Performed ductwork fabrication and installation for commercial tenant build-outs, including sheet metal layout, spiral duct assembly, and balancing"
• "Ran copper refrigerant lines, brazed joints, pulled vacuum, and charged systems on commercial rooftop packaged units"

Generic descriptions that get flagged:

• "Performed HVAC work"
• "Assisted with various projects"
• "Managed installations"

Tax Record Matching

Both boards require tax documentation that corroborates the employment dates listed on your experience affidavit. You'll need to submit W-2 forms (if you were a W-2 employee) or 1099-MISC/1099-NEC forms (if you worked as an independent subcontractor) corresponding to each period of claimed experience.

The dates on your tax documents must align with the dates on the affidavit. If your affidavit claims experience from January 2023 through December 2024, you need W-2s or 1099s from both 2023 and 2024 showing compensation from the employer named on the affidavit.

Any mismatch — an affidavit claiming 18 months of experience but only one year of corresponding tax records, or tax records from a different employer than the one who signed the affidavit — will trigger a board review. This is one of the most common causes of application delays.

When Your Former Employer Won't Sign

This is a real and common problem. Technicians frequently leave employers to start competing businesses, and the former employer has no legal obligation to sign your experience affidavit. Some refuse out of spite, others have simply closed their business or become unreachable.

South Carolina allows alternative experience documentation when standard employer verification isn't available. The approach is to build a corroborating package from other sources:

• Tax records (W-2s or 1099s) proving you were compensated for HVAC work during the claimed period
• Notarized reference letters from licensed residential builders, commercial general contractors, or clients who can attest to the specific HVAC work you performed
• Project documentation such as permit records, inspection reports, or work orders bearing your name

The key is that every alternative document must point to the same conclusion: you performed hands-on HVAC work during the claimed period, under appropriate supervision, for the duration stated. The board evaluates the totality of the documentation — no single alternative document replaces the affidavit, but a well-assembled package of corroborating evidence serves the same verification purpose.

1099 Contractors and Self-Employment

If you worked as a 1099 subcontractor rather than a W-2 employee, your experience still counts — but the documentation needs more care. Your 1099-NEC forms prove income, but they don't inherently prove what type of work you did.

Pair your 1099 forms with:

• A signed letter from the general contractor or licensed HVAC company that hired you as a sub, describing the HVAC work you performed
• Copies of building permits that list you or your sole proprietorship as the mechanical contractor or subcontractor
• Client invoices or service agreements that specify HVAC work

Self-employed time where you operated without any license (on work under the licensing thresholds) is harder to verify. The board's stated experience pathways require supervised residential work or commercial experience in the relevant classification, so do not assume self-employed unlicensed work satisfies the requirement.

Timing Your Experience Documentation

For the residential track (RBC): submit your experience documentation as part of your initial application. The board must review and approve your experience before you can register for the PSI exams. Don't wait to gather experience documents after starting the application — assemble them in advance so you can submit a complete package.

For the commercial track (CLB): you can take the PSI exams first and submit experience documentation afterward with your full application package. But don't let this flexibility create a false sense of urgency. Doc 167 and supporting tax records are frequently the slowest piece to assemble — start tracking down former employers and gathering tax documents early.

The South Carolina HVAC License Guide includes a pre-application documentation checklist and the exact formatting both boards expect for experience verification, including how to structure alternative documentation packages when standard employer affidavits aren't available.

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