STATE REFERENCE · HVAC LICENSING & CONTRACTS
Connecticut: HVAC contractor licensing, reciprocity and contract rules.
In Connecticut, HVAC licence: Statewide. CGS §20-334(a): "No person shall engage in, practice or offer to perform the work of any occupation subject to this chapter in this state, including offering…" Residential contracts: Two statutes. (1) For licensed trades, CGS §20-338d(b) (P.A. 21-37, effective January 1, 2022; subsections re-lettered by P.A. 22-104 effective May 24, 2022)… Renewal and CE: CGS §20-335: "All such licenses shall expire annually". Verified 2026-10-14; cites: CGS §§20-330(5), 20-331(a)(3), 20-333(a), 20-333a, 20-334(a), 20-334a(a), 20-334d, 20-335, 20-338d, 20-340, 20-341 and others.
This page lists what Connecticut publishes about licensing an HVAC or mechanical contractor and contracting with homeowners: who issues the licence, whether one is required statewide, the classes and qualifications, insurance or bond minimums, reciprocity with other states, renewal and continuing education, and the state's home-improvement contract statute if it has one.
It is built for owners of residential HVAC companies, especially those hiring across a state line or opening a second territory. Every entry is a snapshot of what the cited source published on the verification date; it is a research starting point, not legal advice.
Connecticut, field by field.
- Contractor licensing authority
- Connecticut Department of Consumer Protection (DCP), Occupational and Professional Licensing, with the Heating, Piping, Cooling and Sheet Metal Work Examining Board (CGS §20-331(a)(3)); licences are issued under CGS Chapter 393 (§§20-330 to 20-341).
- HVAC licence required
- Statewide. CGS §20-334(a): "No person shall engage in, practice or offer to perform the work of any occupation subject to this chapter in this state, including offering to perform such work in any print, electronic, television or radio advertising or listing, unless such person has first obtained a license as provided in section 20-333, or possesses a card of registration from the Labor Department" as a registered apprentice. "Heating, piping and cooling work" means "the installation, repair, replacement, maintenance, inspection, testing or alteration of any apparatus for piping, appliances, devices or accessories for heating systems, including sheet metal work" and the same work on "air conditioning and refrigeration systems" (§20-330(5)). No dollar threshold appears in §20-334. Exemptions in §20-340 include persons employed by federal, state or municipal agencies (§20-340(1)), servicing domestic-size appliances from an existing outlet or connection (§20-340(5)), industrial firms' maintenance employees on their own premises (§20-340(6)), and persons working on single-family residences they own and occupy, subject to municipal inspection (§20-340(11)). Wilful unlicensed practice is a class B misdemeanor (§20-341(a)), the board or Commissioner may impose a civil penalty "not to exceed three thousand dollars for each violation" (§20-341(d)), and a violation "shall be deemed an unfair or deceptive trade practice" (§20-341(f)).
- Licence classes & qualifications
- DCP licence types: S-1 Unlimited Heating, Piping and Cooling Contractor ("all heating, piping and cooling work as defined in section 20-330 of the Connecticut General Statutes") and S-2 journeyperson; D-1 Limited Warm Air, Air Conditioning and Refrigeration Contractor ("any warm air, air conditioning and refrigeration system" with associated piping and pumping equipment; "This license does not include the installation or servicing of oil burners of any size") and D-2 journeyperson; S-9 Limited Heating Cooling Contractor (heating, hot water and steam systems in buildings not over three stories with a heating load not exceeding 500,000 BTU and steam pressure not exceeding 15 pounds, and "cooling installations up to 35 tons per system") and S-10 journeyperson; B-1/B-2 Limited Gas and Oil Burner. Contractor licence: a person who "has served as a journeyman in the trade for which such person seeks a license for not less than two years" or "has furnished satisfactory evidence of education and experience and has passed an examination" (CGS §20-334a(a)(1)(A)); journeyperson licence: a bona fide apprenticeship "including not less than four years' experience in the trade" plus the state licensure examination (§20-334a(a)(2)(A)). DCP's equivalent-experience chart: S-1 requires 12,000 on-the-job hours and 576 classroom hours; D-1 requires 8,000 on-the-job hours and 432 classroom hours; S-9 requires 10,000 and 576. Application fee $150 for a contractor licence and $90 for a journeyperson licence (§20-333(a)); initial licence fee $150 for a contractor and $120 for any other licence (§20-335).
- Insurance / bond minimum
- No general-liability minimum or surety bond for the heating, piping and cooling licence appears in Chapter 393 as read. CGS §20-334a(a)(1)(C) requires a contractor licensee to "furnish the board or the department with evidence that such licensee will comply with all state requirements pertaining to workers' compensation and unemployment insurance" before the licence issues. Home Improvement Contractor registration under Chapter 400 requires proof of general liability insurance "in an amount not less than twenty thousand dollars" (§20-421(a)(3)), and §20-428(4) exempts licensed trades working within the scope of their licence from Chapter 400.
- Reciprocity
- CGS §20-333a: the Commissioner of Consumer Protection "may, upon the payment of the appropriate fee, as provided in section 20-335, grant a license ... without an examination, to any currently practicing, competent person who holds a similar license" from a state with licensure requirements "substantially similar to, or higher than, those of this state" whose licensing authority may grant the same to Connecticut licensees. DCP's out-of-state page sets the test as a licence that "required the same number of classroom hours" and on-the-job training hours as the Connecticut licence (S-1: 576 classroom and 12,000 OJT hours; D-1: 432 and 8,000) with curriculum equivalent to Exhibit A; no states are named — None published by state name.
- Renewal & continuing education
- CGS §20-335: "All such licenses shall expire annually"; renewal fee "one hundred fifty dollars in the case of a contractor and of one hundred twenty dollars for any other such license"; the board may renew if the application is received "no later than one month after the date of expiration"; a licensee lapsed for over two years "shall have it reinstated only upon complying with the requirements of section 20-333". Continuing education: No CE requirement published for heating, piping and cooling licences — CGS §20-334d imposes continuing professional education on electricians (regulations "shall require not less than four hours per year") and plumbers ("not more than a total of seven hours of accredited continuing professional education every two years") only, and DCP's Continuing Education directory page lists Electrical and Plumbing licences and does not list heating, piping and cooling licences.
- Home-improvement contract rule
- Two statutes. (1) For licensed trades, CGS §20-338d(b) (P.A. 21-37, effective January 1, 2022; subsections re-lettered by P.A. 22-104 effective May 24, 2022): "No written contract to perform work on a private residence by a contractor licensed pursuant to this chapter ... shall be valid or enforceable against an owner unless such contract: (1) Is signed by the owner and the contractor or business; (2) contains the entire agreement between the owner and the contractor or business; (3) contains the date of the transaction; (4) contains the name and address of the contractor and the contractor's license number ...; (5) contains the name and license number of any licensees performing the work ...; (6) contains a notice disclosing the owner's cancellation rights in accordance with the provisions of chapter 740 ...; and (7) contains a starting date and completion date"; the owner may not cancel only where the contract is for emergency or immediate repairs and the owner signed a dated written waiver beforehand (§20-338d(c)); a free copy is due at signing and each change must be in writing and signed (§20-338d(d)-(e)). (2) Home Improvement Act, CGS §§20-418 to 20-432: no person shall hold out as a home improvement contractor without a certificate of registration (§20-420(a)); "home improvement" covers repair, replacement, remodeling and alteration of a private residence where the total price "exceeds two hundred dollars" (§20-419(5)(A)), and "Contractor" excludes a person whose home improvement contracts total $1,000 or less in any twelve months (§20-419(4)(B)); §20-428(4) exempts "any person holding a current professional or occupational license issued pursuant to the general statutes ... provided such person engages only in that work for which such person is licensed"; §20-429(a)(1)(A) makes a home improvement contract unenforceable against the owner unless it is in writing, signed by owner and contractor, contains the entire agreement, the date, the contractor's name, address and registration number, a chapter 740 cancellation notice, start and completion dates, is entered into by a registered salesman or contractor and discloses the owner's other contractor entities of the previous five years; every home improvement contract "shall be considered a home solicitation sale pursuant to chapter 740 and shall be subject to the requirements of said chapter regardless of the location of the transaction or of the signing of the contract" (§20-429(e)); registrations "shall expire annually on March thirty-first" (§20-427(f)). No statutory deposit cap appears in either statute as read. DCP's consumer page on home improvement contracts states "Connecticut law requires a written contract for every home improvement job", lists the required HIC registration number, signing, start, completion and cancellation dates, and the "Notice of the Customer's Right to Cancel within three business days after signing the contract" attached in duplicate; DCP's release of May 7, 2025 and the Attorney General's home-improvement page repeat the written-contract and three-business-day cancellation requirements.
Download Connecticut's row (CSV) · all 51 states (CSV) · CC BY 4.0, attribute Vertical OS and link to this page.
Where this comes from.
Cited. CGS §§20-330(5), 20-331(a)(3), 20-333(a), 20-333a, 20-334(a), 20-334a(a), 20-334d, 20-335, 20-338d, 20-340, 20-341; CGS §§20-418, 20-419, 20-420(a), 20-421(a)(3), 20-427(f), 20-428(4), 20-429
Status. Verified — cited, last verified 2026-10-14. Start with the licensing authority link — it is the primary source. The licence-required and home-improvement-contract rows decide what you can sign and sell, so read both against the cited statute before changing a contract or a service area. The verification status says how much of the row was read at the source.
What to confirm.
Confirm with DCP ([email protected]) the current examination and fee schedule, the annual expiration date it sets for S-1/D-1 licences, and whether any continuing-education requirement has been adopted for heating, piping and cooling licences since the pages were read on 2026-10-14; DCP's Home Improvement Contractor registration application page was not located (the statute, Chapter 400, and DCP's consumer page on home improvement contracts were read instead). cga.ct.gov returned HTTP 403 to WebFetch and was read by direct HTTP fetch.
Connecticut, answered from the row.
Does Connecticut require a state licence for HVAC contractors?
Statewide. CGS §20-334(a): "No person shall engage in, practice or offer to perform the work of any occupation subject to this chapter in this state, including offering to perform such work in any print, electronic, television or radio advertising or listing, unless such person has first obtained a license as provided in section 20-333, or possesses a card of registration from the Labor Department" as a registered apprentice. "Heating, piping and cooling work" means "the installation, repair, replacement, maintenance, inspection, testing or alteration of any apparatus for piping, appliances, devices or accessories for heating systems, including sheet metal work" and the same work on "air conditioning and refrigeration systems" (§20-330(5)). No dollar threshold appears in §20-334. Exemptions in §20-340 include persons employed by federal, state or municipal agencies (§20-340(1)), servicing domestic-size appliances from an existing outlet or connection (§20-340(5)), industrial firms' maintenance employees on their own premises (§20-340(6)), and persons working on single-family residences they own and occupy, subject to municipal inspection (§20-340(11)). Wilful unlicensed practice is a class B misdemeanor (§20-341(a)), the board or Commissioner may impose a civil penalty "not to exceed three thousand dollars for each violation" (§20-341(d)), and a violation "shall be deemed an unfair or deceptive trade practice" (§20-341(f)). — Connecticut Department of Consumer Protection (DCP), Occupational and Professional Licensing, with the Heating, Piping, Cooling and Sheet Metal Work Examining Board (CGS §20-331(a)(3)); licences are issued under CGS Chapter 393 (§§20-330 to 20-341).
What are the HVAC licence classes and qualifications in Connecticut?
DCP licence types: S-1 Unlimited Heating, Piping and Cooling Contractor ("all heating, piping and cooling work as defined in section 20-330 of the Connecticut General Statutes") and S-2 journeyperson; D-1 Limited Warm Air, Air Conditioning and Refrigeration Contractor ("any warm air, air conditioning and refrigeration system" with associated piping and pumping equipment; "This license does not include the installation or servicing of oil burners of any size") and D-2 journeyperson; S-9 Limited Heating Cooling Contractor (heating, hot water and steam systems in buildings not over three stories with a heating load not exceeding 500,000 BTU and steam pressure not exceeding 15 pounds, and "cooling installations up to 35 tons per system") and S-10 journeyperson; B-1/B-2 Limited Gas and Oil Burner. Contractor licence: a person who "has served as a journeyman in the trade for which such person seeks a license for not less than two years" or "has furnished satisfactory evidence of education and experience and has passed an examination" (CGS §20-334a(a)(1)(A)); journeyperson licence: a bona fide apprenticeship "including not less than four years' experience in the trade" plus the state licensure examination (§20-334a(a)(2)(A)). DCP's equivalent-experience chart: S-1 requires 12,000 on-the-job hours and 576 classroom hours; D-1 requires 8,000 on-the-job hours and 432 classroom hours; S-9 requires 10,000 and 576. Application fee $150 for a contractor licence and $90 for a journeyperson licence (§20-333(a)); initial licence fee $150 for a contractor and $120 for any other licence (§20-335).
What insurance or bond does Connecticut require for an HVAC licence?
No general-liability minimum or surety bond for the heating, piping and cooling licence appears in Chapter 393 as read. CGS §20-334a(a)(1)(C) requires a contractor licensee to "furnish the board or the department with evidence that such licensee will comply with all state requirements pertaining to workers' compensation and unemployment insurance" before the licence issues. Home Improvement Contractor registration under Chapter 400 requires proof of general liability insurance "in an amount not less than twenty thousand dollars" (§20-421(a)(3)), and §20-428(4) exempts licensed trades working within the scope of their licence from Chapter 400.
Does Connecticut have HVAC licence reciprocity with other states?
CGS §20-333a: the Commissioner of Consumer Protection "may, upon the payment of the appropriate fee, as provided in section 20-335, grant a license ... without an examination, to any currently practicing, competent person who holds a similar license" from a state with licensure requirements "substantially similar to, or higher than, those of this state" whose licensing authority may grant the same to Connecticut licensees. DCP's out-of-state page sets the test as a licence that "required the same number of classroom hours" and on-the-job training hours as the Connecticut licence (S-1: 576 classroom and 12,000 OJT hours; D-1: 432 and 8,000) with curriculum equivalent to Exhibit A; no states are named — None published by state name.
How often is an HVAC licence renewed in Connecticut, and is continuing education required?
CGS §20-335: "All such licenses shall expire annually"; renewal fee "one hundred fifty dollars in the case of a contractor and of one hundred twenty dollars for any other such license"; the board may renew if the application is received "no later than one month after the date of expiration"; a licensee lapsed for over two years "shall have it reinstated only upon complying with the requirements of section 20-333". Continuing education: No CE requirement published for heating, piping and cooling licences — CGS §20-334d imposes continuing professional education on electricians (regulations "shall require not less than four hours per year") and plumbers ("not more than a total of seven hours of accredited continuing professional education every two years") only, and DCP's Continuing Education directory page lists Electrical and Plumbing licences and does not list heating, piping and cooling licences.
What does Connecticut require in a residential HVAC contract?
Two statutes. (1) For licensed trades, CGS §20-338d(b) (P.A. 21-37, effective January 1, 2022; subsections re-lettered by P.A. 22-104 effective May 24, 2022): "No written contract to perform work on a private residence by a contractor licensed pursuant to this chapter ... shall be valid or enforceable against an owner unless such contract: (1) Is signed by the owner and the contractor or business; (2) contains the entire agreement between the owner and the contractor or business; (3) contains the date of the transaction; (4) contains the name and address of the contractor and the contractor's license number ...; (5) contains the name and license number of any licensees performing the work ...; (6) contains a notice disclosing the owner's cancellation rights in accordance with the provisions of chapter 740 ...; and (7) contains a starting date and completion date"; the owner may not cancel only where the contract is for emergency or immediate repairs and the owner signed a dated written waiver beforehand (§20-338d(c)); a free copy is due at signing and each change must be in writing and signed (§20-338d(d)-(e)). (2) Home Improvement Act, CGS §§20-418 to 20-432: no person shall hold out as a home improvement contractor without a certificate of registration (§20-420(a)); "home improvement" covers repair, replacement, remodeling and alteration of a private residence where the total price "exceeds two hundred dollars" (§20-419(5)(A)), and "Contractor" excludes a person whose home improvement contracts total $1,000 or less in any twelve months (§20-419(4)(B)); §20-428(4) exempts "any person holding a current professional or occupational license issued pursuant to the general statutes ... provided such person engages only in that work for which such person is licensed"; §20-429(a)(1)(A) makes a home improvement contract unenforceable against the owner unless it is in writing, signed by owner and contractor, contains the entire agreement, the date, the contractor's name, address and registration number, a chapter 740 cancellation notice, start and completion dates, is entered into by a registered salesman or contractor and discloses the owner's other contractor entities of the previous five years; every home improvement contract "shall be considered a home solicitation sale pursuant to chapter 740 and shall be subject to the requirements of said chapter regardless of the location of the transaction or of the signing of the contract" (§20-429(e)); registrations "shall expire annually on March thirty-first" (§20-427(f)). No statutory deposit cap appears in either statute as read. DCP's consumer page on home improvement contracts states "Connecticut law requires a written contract for every home improvement job", lists the required HIC registration number, signing, start, completion and cancellation dates, and the "Notice of the Customer's Right to Cancel within three business days after signing the contract" attached in duplicate; DCP's release of May 7, 2025 and the Attorney General's home-improvement page repeat the written-contract and three-business-day cancellation requirements.
Not legal advice. Every row is a dated snapshot of published sources; licensing rules and contract statutes change, and cities and counties add their own permit and licence requirements. Confirm every entry with the named authority and your own counsel before relying on it.
This table is free, open data.
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