How to Start an HVAC Business in New Hampshire (2026)

Last updated: May 4, 2026

New Hampshire HVAC licensing is category-specific: there is no single statewide “HVAC contractor license.” Instead, the NH OPLC Mechanical Safety and Licensing Board licenses individuals by the type of mechanical work they perform — with a four-tier fuel gas fitter ladder for gas work and a separate voluntary Oil Heating Technician certification for oil-fired systems. The Mechanical Business Entity License ($275) is required for businesses providing gas, plumbing, domestic appliance, or hearth services. If you only do refrigeration and air conditioning without any gas connections, you may not need a state individual mechanical license — but you still need federal EPA 608 certification for refrigerant handling. NH updated its mechanical codes to the 2021 IBC/IMC/IFGC standards effective July 1, 2024.

New Hampshire’s HVAC market is driven by a critical climate reality: this is genuine four-season country. Manchester winters routinely see temperatures of -5°F to -20°F. The White Mountains record some of the most extreme wind chill readings in the continental US. Oil-heated homes remain common throughout rural NH, and the transition from oil to heat pump and propane systems is accelerating with IRA 25C tax credit incentives. The southern NH corridor (Manchester, Nashua) has the densest commercial and residential market. The Lakes Region and White Mountains have a strong seasonal demand spike for HVAC system inspections and repairs at vacation properties before summer and ski-season occupancy.

HVAC Business Requirements in New Hampshire at a Glance

Requirement	Agency	Cost	Timeline
Fuel Gas Fitter — Trainee license	NH OPLC Mechanical Safety and Licensing Board	~$88 application; ~$88 biennial renewal	Entry-level; work under licensed supervisor
Fuel Gas Fitter — Piping Installer license	NH OPLC Mechanical Safety and Licensing Board	~$198 application; ~$198 biennial renewal	Requires 1,000+ hours + 60 hours approved training
Fuel Gas Fitter — Installation Technician license	NH OPLC Mechanical Safety and Licensing Board	~$198 application; ~$198 biennial renewal	Requires 1,000+ hours + 100 hours training (or 40 extra if hold PI license)
Fuel Gas Fitter — Service Technician license	NH OPLC Mechanical Safety and Licensing Board	~$198 application; ~$198 biennial renewal	Requires 2,000+ hours + 140 hours training
Mechanical Business Entity license	NH OPLC Mechanical Safety and Licensing Board	~$275 application; ~$275 biennial renewal	Required for businesses providing gas/plumbing/hearth services
Oil Heating Technician certification (voluntary)	NH OPLC Mechanical Safety and Licensing Board	$50 application; $50 biennial renewal	Requires NORA or NATE certification + 4,000 documented field hours
EPA 608 Universal certification	EPA-approved certifying organization	$20-$60 exam fee	Federal requirement; before handling regulated refrigerants
LLC formation	NH Secretary of State	$100-$102	1-3 business days
Annual LLC report	NH Secretary of State	$100/year; due April 1	Annual
General liability insurance ($1M+)	Licensed private carrier	$1,500-$4,000/year	Before operating
Workers compensation (if employees)	Licensed private carrier	Varies by payroll; 6.1% rate cut 2026	Required at first employee

How to Start an HVAC Business in New Hampshire (Step by Step)

Step 1: Understand the NH Mechanical Licensing Structure

NH’s approach to HVAC licensing is dictated by what you work on, not what you call yourself. The critical distinctions:

Fuel Gas Work (Natural Gas and Propane) — License Required

The NH OPLC Mechanical Safety and Licensing Board issues four tiers of individual fuel gas fitter licenses:

• Trainee: Entry-level; must work under a licensed fuel gas fitter’s supervision. Application and biennial renewal approximately $88. Minimum age 16. Must complete a board-approved training program while working.
• Piping Installer: Authorizes installation of gas piping systems. Application and biennial renewal approximately $198. Requires: minimum 1,000 hours of work experience relevant to gas piping installation, plus at least 60 hours of approved training.
• Installation Technician: Authorizes installation, service, and repair of gas appliances and equipment. Application and biennial renewal approximately $198. Requires: minimum 1,000 hours of relevant experience, plus 100 hours of training (or 40 additional hours if you already hold a Piping Installer license).
• Service Technician: The most comprehensive individual fuel gas license — authorizes installation, service, and repair of gas appliances at a higher complexity level. Application and biennial renewal approximately $198. Requires: minimum 2,000 hours of experience plus 140 hours of training (or 40 additional hours if you hold an Installation Technician license).

Mechanical Business Entity License — Required for Businesses

If your business entity (LLC, corporation, partnership) provides gas, plumbing, domestic appliance, or hearth services, the business itself must hold a Mechanical Business Entity License. Application and biennial renewal approximately $275. This license is distinct from the individual fuel gas fitter license held by your technicians — both are required for a gas-work HVAC business.

Oil Heating Work — Voluntary Certification

The Oil Heating Technician certification is a voluntary professional credential administered by OPLC. It requires: current NORA (National Oilheat Research Alliance) or NATE (North American Technician Excellence) certification, plus 4,000 documented field hours of oil heating work experience. Application and biennial renewal: $50. While not legally required, holding this certification is a market differentiator in NH’s substantial oil-heated home market — demonstrating to customers and insurers that your technicians meet a nationally recognized standard.

Refrigeration and AC Only (No Gas) — State License Not Required for Individuals

General air conditioning and refrigeration work without gas connections does not currently require a state individual mechanical license under NH rules. However, if your business entity provides these services along with any gas, plumbing, or hearth work, the Mechanical Business Entity License is still required. And regardless of state license status, EPA 608 certification is federally mandatory for all refrigerant handling.

Contact OPLC to verify current requirements before applying:

• Email: OPLCLicensing5@oplc.nh.gov
• Address: 7 Eagle Square, Concord, NH 03301
• Website: oplc.nh.gov/mechanical-safety-and-licensing-board
• Applications: oplc.nh.gov/applications-mechanical-safety-and-licensing

Important: Rules Mec 300 (Initial License Requirements) and Mec 604 (Training and Examination Provider Approval) became effective February 13, 2026. Verify any application with OPLC against the current rules.

Step 2: Obtain EPA 608 Universal Certification

Federal law under Clean Air Act Section 608 requires certification for any technician who handles regulated refrigerants — purchasing, recovering, recycling, or reclaiming HFCs, HCFCs, and CFCs. This is a federal requirement with no state exemption:

• Type I: Small appliances (5 lbs or less of refrigerant — window ACs, mini-fridges)
• Type II: High-pressure refrigerants (R-22, R-410A, R-454B) — most residential and light commercial HVAC
• Type III: Low-pressure refrigerants (R-11, R-123) — large commercial chillers
• Universal: Covers all three types — strongly recommended for any full-service HVAC technician

Take the exam through any EPA-approved organization (ESCO Institute, HVAC Excellence, and many others). Exam cost: typically $20-$60. Universal certification does not expire.

A2L Refrigerant Transition (2025-2026)

Beginning January 1, 2025, EPA AIM Act regulations phased out the manufacture of R-410A systems. R-32 and R-454B (both A2L “mildly flammable” refrigerants) are now the primary low-GWP alternatives. If your technicians will work on A2L systems, they need additional A2L-specific safety training beyond standard EPA 608. The transition is already underway in NH — new residential equipment shipped in 2025-2026 is predominantly A2L. Plan your technician training accordingly.

Step 3: Apply for NH OPLC Mechanical Licenses

Download applications from oplc.nh.gov/applications-mechanical-safety-and-licensing. The process involves:

1. Select the correct license type (Trainee, Piping Installer, Installation Technician, or Service Technician for individuals; Mechanical Business Entity for the LLC)
2. Gather supporting documentation: proof of work hours, proof of completed training, any existing certifications
3. Pay applicable fees (biennial license period)
4. Submit application and await processing

For the Mechanical Business Entity license, the business entity must be formed (LLC registered with SOS) before applying, as the license is issued to the entity.

Step 4: Form Your Business Entity

Register your HVAC business as an LLC with the NH Secretary of State at quickstart.sos.nh.gov. Formation fee: $100-$102. Annual report: $100, due April 1. Get a free EIN from the IRS and open a dedicated business checking account. The Mechanical Business Entity license is issued in the LLC’s name — form your entity before applying for the business-level license.

Step 5: Get Business Insurance

HVAC businesses carry some of the highest liability risks in the trades: gas leaks, carbon monoxide exposure, improper refrigerant handling, property damage from water and fire, and equipment failure. Minimum recommended coverage:

• General liability: $1,000,000 per occurrence / $2,000,000 aggregate. Many commercial accounts and property managers require $2M. OPLC may require proof of GL for the Mechanical Business Entity license.
• Commercial auto: Required for any vehicle used for business purposes. Personal auto policies exclude commercial use. Covers your service van and any towed trailers or equipment.
• Workers compensation: Required for any employer with any employees under NH RSA 281-A:5. NH approved a 6.1% loss cost reduction for 2026 — the 14th consecutive annual decrease. NCCI Class 5183 (HVAC) applies to most installation and service work.
• Inland marine (equipment floater): Covers diagnostic tools, recovery machines, pipe benders, and other job-site equipment if stolen or damaged.

Step 6: Register for NH Business Taxes

New Hampshire has no sales tax on HVAC services — neither labor nor materials on a lump-sum contract are subject to NH sales tax. However:

• Business Profits Tax (BPT): If gross business income exceeds $109,000, file Form NH-1065 (LLCs/partnerships) and pay 7.5% on net profits. Register with NH DRA at revenue.nh.gov.
• Business Enterprise Tax (BET): If gross receipts exceed $298,000, file the BET at 0.55% of the enterprise value base (compensation paid + interest + dividends). BET credit applies against BPT.
• UI taxes: Register with NHES at nhes.nh.gov if hiring. New employer rate: 2.7% on the first $14,000 per employee per year.

New Hampshire HVAC Market: Regional Demand Patterns

NH’s climate profile drives specific demand patterns. The southern tier — Manchester, Nashua, and the Merrimack Valley — has the densest market for residential and light commercial HVAC. New construction in Hillsborough and Rockingham Counties (driven by MA-border migration) creates steady replacement and new-installation work. The oil-to-heat-pump conversion market is particularly active: NH ranks among the highest oil-heated home concentrations in the United States, and the IRA 25C tax credit (up to $2,000 per household for qualifying heat pump installation) plus utility rebates from Eversource and Liberty Utilities create incentive-driven demand for heat pump upgrades.

The vacation property market (Lakes Region, White Mountains) generates concentrated seasonal demand for pre-season HVAC inspections and repairs. A Laconia or North Conway HVAC contractor can build a substantial business on seasonal startup checks for the region’s thousands of vacation homes. The Upper Valley (Hanover/Lebanon) market is driven by Dartmouth Health’s large healthcare campus and the professional demographic of the Dartmouth College community — both generating institutional and residential HVAC demand with customers who prioritize licensed, bonded, and fully insured contractors.

Cost to Start an HVAC Business in New Hampshire

Item	Cost	Notes
LLC formation (Secretary of State)	$100-$102	One-time
Annual LLC report	$100/year	Due April 1
Fuel Gas Fitter license (individual, Service Technician level)	~$198 application	Biennial renewal ~$198
Mechanical Business Entity license	~$275 application	Biennial renewal ~$275
EPA 608 Universal exam	$20-$60	One-time; federal requirement
General liability insurance ($1M)	$1,500-$4,000/year	Annual; NCCI Class 5183
Commercial auto insurance	$1,200-$3,000/year	Annual; per service vehicle
HVAC tools and diagnostic equipment	$3,000-$15,000	One-time startup; varies by specialty
Service van (used)	$15,000-$50,000+	Major startup cost; leasing also available
Year 1 Total (solo technician, existing van)	~$7,000-$22,000	Licensing + insurance + tools

Related New Hampshire Business Guides

• How to Start a Cleaning Service in New Hampshire
• How to Start a Food Truck in New Hampshire
• How to Start a Daycare in New Hampshire
• How to Start a Hair Salon in New Hampshire
• How to Start a Landscaping Business in New Hampshire
• How to Become a Private Investigator in New Hampshire

← Back to all New Hampshire business guides

Frequently Asked Questions

Do I need a state license to do HVAC work in New Hampshire?

It depends on your work type. If you work with fuel gas systems (natural gas or propane), you need a fuel gas fitter license from the NH OPLC Mechanical Safety and Licensing Board — one of four tiers depending on experience and training: Trainee (~$88), Piping Installer (~$198), Installation Technician (~$198), or Service Technician (~$198). If your business entity provides gas, plumbing, domestic appliance, or hearth services, the Mechanical Business Entity License (~$275) is additionally required. Refrigeration/AC-only work without gas connections does not require an individual state mechanical license, but verify with OPLC. Federal EPA 608 certification is required for all refrigerant handling regardless of state license status.

What is the Mechanical Business Entity License and who needs it?

The Mechanical Business Entity License (~$275 application, biennial renewal ~$275) is required for any business entity — LLC, corporation, or partnership — that provides gas, plumbing, domestic appliance, or hearth services in New Hampshire. It is issued to the business itself, not to individual technicians. Even if your individual technicians hold valid fuel gas fitter licenses, the business entity must separately hold this license to legally offer these services as a company. Contact OPLC at OPLCLicensing5@oplc.nh.gov for current requirements.

What is the Oil Heating Technician certification and is it required?

The Oil Heating Technician certification is a voluntary credential issued by the NH OPLC Mechanical Safety and Licensing Board. It costs $50 (application and biennial renewal) and requires current NORA or NATE certification plus 4,000 documented hours of oil heating field experience. It is not legally required to work on oil-fired systems in NH, but it is a recognized market differentiator — particularly relevant given the high proportion of oil-heated homes in rural New Hampshire and the active oil-to-heat-pump conversion market.

Do NH HVAC businesses need workers compensation?

Yes. NH RSA 281-A:5 requires workers compensation for every employer with any employees — no minimum threshold. Even one part-time helper triggers the requirement. NH approved a 6.1% workers comp loss cost reduction for 2026, the 14th consecutive annual decrease. NCCI Class 5183 applies to most HVAC installation and service work. Purchase from any licensed NH carrier or the NCCI Assigned Risk Pool at 800-622-4123. More info at dol.nh.gov/workers-compensation.

What is the A2L refrigerant transition and how does it affect NH HVAC businesses?

Under EPA AIM Act regulations, the manufacture of R-410A-based HVAC systems was phased out beginning January 1, 2025. New residential equipment shipped in 2025-2026 uses A2L refrigerants — primarily R-32 and R-454B — which are classified as “mildly flammable.” Installation and service of A2L systems requires additional safety training beyond standard EPA 608 certification because the flammability properties of these refrigerants differ from the HFCs technicians have traditionally used. NH HVAC businesses should ensure all technicians handling A2L systems complete A2L-specific training from an approved provider.

Does NH have a general contractor license that covers HVAC?

New Hampshire does not have a general contractor license equivalent to, say, Florida’s CGC license. HVAC work is specifically licensed through the OPLC Mechanical Safety and Licensing Board for the gas and plumbing components. Purely non-gas, non-plumbing mechanical installation (e.g., ductwork without gas connections) may fall outside the formal licensing requirement — but any work connecting to gas supply lines, gas appliances, oil-fired equipment, or domestic water systems triggers the applicable mechanical license requirements.