HVAC Contractor License Requirements in California

Overview — hvac licensing in California

California requires a state-level hvac contractor license, issued by the Contractors State License Board (CSLB). The license verifies competence and consumer protection, and is required to legally bid and perform hvac work in the state. Working without one when required is typically a misdemeanor and exposes the contractor to civil penalties — and the contract becomes unenforceable in court.

License classes available

California offers 2 hvac license classes — pick based on the largest project you plan to bid:

• C-20 Warm-Air Heating, Ventilating and Air-Conditioning Contractor. Standard CA HVAC license. Covers installation, alteration, repair of warm-air systems, AC, refrigeration, ductwork.
• C-38 Refrigeration Contractor. Limited to refrigeration only. Common companion to C-20 for commercial HVAC pros.

Experience required

4 years of journey-level HVAC experience in past 10 years.

Exam — what you're tested on

California requires a written examination administered by PSI Services (CSLB-administered). Topics covered:

• California Mechanical Code
• Refrigerant handling
• Title 24 energy compliance
• Business and law

Passing score: 73%. Up to 4 attempts per year are allowed.

Fees

• Application fee: $450
• Initial license fee: $200
• Renewal fee: $450 ( biennial)

Bond & insurance

Bond: Required — typically $25,000. Standard CSLB contractor bond.

General liability insurance: Minimum $1,000,000.

Workers' compensation: Required for 1+ employees.

Reciprocity with other states

California has reciprocity agreements with: AZ, NV, UT, LA. Reciprocity typically waives the trade exam if you hold an equivalent license in good standing in the reciprocal state for at least one year. Each state still requires its own application and business/law exam.

Local permits and requirements

Every CA city requires HVAC permits. Title 24 documentation mandatory on most jobs.

Common gotchas

Things that catch most applicants on their first license cycle in California:

• EPA Section 608 certification (separate from C-20) required to handle refrigerants.
• Title 24 HERS testing (HVAC duct leakage, AC charge) required on most replacements.
• California's energy codes demand higher-efficiency systems than IECC baseline.
• Sales tax on HVAC: labor on residential is not taxable but materials are.

Frequently asked questions

Does California's C-20 cover refrigeration?

Limited refrigeration is covered (e.g., walk-in coolers). For purely refrigeration work, C-38 is appropriate. Most pros hold both.

What is EPA Section 608 and is it separate from C-20?

Yes, separate. EPA Section 608 is federal and required to handle refrigerants. Pass a 100-question exam (Type I, II, III, or Universal). C-20 is the state contractor license. Both are required to legally service AC.

What's Title 24 HERS for HVAC?

HERS = Home Energy Rating System. Required for AC change-outs and heat-pump installs. A third-party rater must verify duct leakage and refrigerant charge. Failed HERS = failed inspection.

How long does C-20 licensing take?

4–6 months from application to active license.

Does California require CE for C-20?

No state CE for the contractor license. EPA 608 is one-time (no renewal). HERS rater certifications have their own renewal cycles.