Michigan HVAC License Requirements

Michigan doesn't issue a single "HVAC license." The state regulates heating, ventilation, air conditioning, and refrigeration work through a Mechanical Contractor License administered by the Department of Licensing and Regulatory Affairs (LARA) under the Skilled Trades Regulation Act (PA 407 of 2016). If you want to contract for HVAC work, pull permits, or run your own shop, you need this credential — and it has real teeth behind it.

Do You Actually Need a License?

Yes, if you're performing mechanical work for compensation. Michigan's licensing requirement applies regardless of project value. Unlike general residential construction, which exempts alterations under $600 from state builder licensing, specialty trades like HVAC have no dollar-amount threshold. A $200 thermostat swap done for pay still requires a licensed contractor of record.

The penalties for unlicensed work are steep: misdemeanor criminal charges, fines between $5,000 and $25,000, and the loss of your right to file a mechanics lien on residential projects. That last one stings — it means you can't use a mechanics lien to secure payment on the affected residential project.

The key distinction most technicians miss: holding an EPA Section 608 certification does not grant you any contracting authority in Michigan. EPA 608 covers refrigerant handling under the federal Clean Air Act. It doesn't let you bid jobs, install systems, pull permits, or operate a business. You need both credentials if your work involves refrigerants.

The Three Experience and Education Paths

For the standard classifications on a Michigan Mechanical Contractor License, three years (6,000 hours) of documented experience is required. Classifications G and H instead require three years of active licensure in Class E or F, respectively, or an equivalent qualification. You can satisfy part of the standard requirement through education:

• Standard field experience: 6,000 hours under a licensed contractor, documented with notarized affidavits signed under penalty of perjury by your employers
• HVAC technical degree: An approved associate degree or certificate can substitute for up to 2,000 hours (one year) of the three-year requirement
• Registered apprenticeship: Completion of a U.S. Department of Labor-approved program also substitutes up to 2,000 hours

Military veterans get full credit for documented active-duty mechanical work, supported by DD214 and DD215 forms plus a commanding officer's experience affidavit.

The experience verification is where most applications stall. LARA doesn't accept vague employment letters or self-certified hours. Your former employers must provide granular descriptions of the work you performed — including equipment BTU ratings, fuel types, duct configurations, and refrigerant classes. Descriptions like "performed residential HVAC service" get rejected.

The LARA Application Process

Once your experience documentation is assembled:

1. Create a MiPLUS account on LARA's Accela portal (do not create a duplicate if you previously held a trainee registration — duplicates disrupt the database and delay processing)
2. Submit your Mechanical Contractor application with all experience affidavits and pay the $300 non-refundable state fee
3. Disclose any criminal history — a conviction isn't automatic grounds for denial under PA 407, but failure to disclose one is grounds for immediate rejection
4. Wait for your Authorization to Test — LARA's review typically takes four to eight weeks during peak construction season

That $300 fee is non-refundable regardless of outcome. If LARA rejects your application for incomplete documentation, you forfeit the fee and restart from scratch.

PSI Exam Requirements

After LARA approves your application, your eligibility transfers to PSI Services LLC for examination. You have exactly 365 days from your approval date to pass the required exams. Miss that window, and your application expires — fees and all.

The HVAC Equipment exam (Classification B) costs $100 and consists of 150 questions over three hours. All other classification exams cost $50 each, with 55 questions and a one-hour time limit. Every exam is open-book, but you must bring your own bound reference materials — no loose pages, photocopies, or handwritten notes allowed.

PSI operates testing centers in Dearborn, Holt, Southfield, Grand Rapids, Gaylord, and Marquette.

Choosing Your Classifications

Michigan offers ten mechanical contractor classifications under MCL 339.5807. You need a separate exam for each classification you want on your license:

• Classification B (HVAC Equipment): Forced-air furnaces, central AC, heat pumps — the bread-and-butter residential classification
• Classification C (Ductwork): Sheet metal, flexible, and fibrous glass duct systems
• Classification D (Refrigeration): Commercial walk-in coolers, split systems, refrigerant lines
• Classification A (Hydronic Heating): Boilers, radiant heat, closed-loop systems
• Classifications E through H: Limited and unlimited heating/refrigeration service tiers
• Classification I (Fire Suppression): Sprinkler systems and fire extinguishing piping
• Classification J (Specialty): Solar thermal, LP distribution, solid fuel appliances

Most residential HVAC contractors start with Classifications B and C, then add D if they handle refrigeration work.

What Comes After the License

Passing your exams and receiving your license is the regulatory starting line, not the finish. You still need to register with every municipality where you plan to pull permits (state law caps local registration fees at $15), bind commercial general liability insurance, confirm whether Michigan's employer triggers require workers' compensation if you hire anyone, and maintain 6 hours of approved continuing education per three-year renewal cycle.

The Michigan HVAC License Guide maps this entire sequence — from experience documentation through local permit registration — so you can see every administrative step before spending your $300 on the state application.

See more Michigan guides →