How to Choose an HVAC Contractor in Ontario 2026: Complete Verification Guide

Why verification matters

Ontario regulates HVAC work through several independent bodies because the work touches three distinct hazards: combustion gases, refrigerants, and high-voltage wiring. Each hazard has its own regulator, its own license, and its own public registry. A contractor who is legitimate in one area is not automatically authorized in the others. Verifying credentials is the only way to know the crew showing up at your door is allowed to do the specific work you are paying for.

The authority map is worth understanding before you make a single phone call. TSSA, the Technical Standards and Safety Authority, governs fuels work under Ontario Regulation 212/01 and issues both the company registration (the Fuels Contractor authorization) and the individual G1, G2, and G3 technician certificates.[3] ESA, the Electrical Safety Authority, administers the Ontario Electrical Safety Code and issues the ECRA/ESA license that every Licensed Electrical Contractor must hold before pulling permits or performing wiring work.[6] Skilled Trades Ontario is the newer successor to the Ontario College of Trades and maintains the public register for the 313A and 313D compulsory trade certificates.[4] HRAI is an industry association, not a regulator, but its voluntary Contractor Division gives member companies access to ongoing training, manufacturer relationships, and a published code of ethics.[8]

Skipping verification carries real consequences. A gas appliance installed by an unregistered contractor may fail inspection, void the manufacturer warranty, and expose you to insurance denial if there is a fire or carbon monoxide incident. Electrical work done without an ECRA/ESA license is not inspected by ESA and may not be covered by your home insurance. Enbridge Gas, the largest natural gas distributor in Ontario, publishes its own Choose a Contractor guidance that reinforces the same basic principle: always verify that your contractor is registered with TSSA before you sign anything.[11] The good news is that every piece of verification you need is public, free, and takes under 10 minutes when you know where to look.

Step 1: Get the business name, TSSA number, and 313A license before they arrive

Verification starts before the site visit. When you contact a contractor for a quote, ask them to email you four things:

• The full legal business name (not just a trade name)
• Their TSSA Fuels Contractor registration number (FS-R prefix)
• The 313A certificate number of the lead technician who will attend
• The ECRA/ESA license number if any electrical work is involved

A contractor operating legally in Ontario will provide all four in under five minutes because these are public credentials they use on permits, warranty claims, and inspection paperwork every day. If the response is evasive, delayed, or a refusal, that is the moment to move on, not after you have signed a contract.

Pay attention to legal names versus trade names. Many HVAC operators run under a catchy brand name (for example "GTA Comfort Pros") while the legal entity registered with TSSA is a numbered company or a different corporate name. That is normal, but you want both. When you search the TSSA registry in Step 2, you will need the legal name that actually appears on the authorization. Ask for the exact name as it appears on the TSSA certificate, and request that they attach a PDF copy of the registration if possible. Many contractors will happily do this because it shortens the sales cycle.

Step 2: TSSA Fuels Contractor Registry lookup

The Technical Standards and Safety Authority maintains the public Authorized Heating Fuel Contractors registry, which is the authoritative source for verifying that a company is legally allowed to perform gas work in Ontario.[1]

Go to tssa.org/fuels-contractor and use the search box. You can search by business name, reference number, city, or postal code. Every listing shows the business name, registration number, registration category (for example Natural Gas or Propane), registration status, and office location. Confirm three things:

• The company name on the listing matches the legal name you were given (watch for similar names, numbered companies, and lookalike spellings)
• The registration status is active, not lapsed, suspended, or revoked
• The registration category covers the work you need. A propane-only registration does not cover natural gas, and vice versa

If the company is not in the registry, they are not authorized to install or service gas appliances in Ontario. Full stop. The registry is updated continuously by TSSA as contractors renew or transition between statuses.[2]

A common edge case: a contractor claims their TSSA number is "pending" because they recently applied or recently changed corporate structure. Pending is not authorized. A pending applicant cannot legally perform gas work until the registration is issued and appears in the public registry. If you hear "pending" during verification, ask for the date of the original application, and ask which other active TSSA-registered company will be performing the work in the meantime. Many legitimate shops will subcontract during a transition period, and they will name the subcontractor in writing.

Step 3: Verify the gas technician's G1, G2, or G3 certification

A registered contractor is only half the picture. The person who actually touches gas on site must hold an individual gas technician certificate issued by TSSA.[3] Gas certificates come in three tiers:

For a typical home, a G2 technician is the right credential. Ask the contractor which technician will be on site and request the certificate number. TSSA is the issuing and verifying body for all gas technician certificates in Ontario. The contractor can confirm in writing that the assigned tech holds a current G2.

Step 4: ESA licensed electrical contractor lookup

Any HVAC installation that adds or changes wiring must be done by a Licensed Electrical Contractor (LEC) holding an active ECRA/ESA license.[5] This applies to most central AC installations, almost every heat pump install, and any job that touches the electrical panel. Importantly, the Electrical Safety Authority is clear that a certified electrician is not the same thing as a licensed electrical contractor, and only an LEC can legally pull an electrical permit on your home.[6]

To verify: go to esasafe.com and use the Find a Licensed Electrical Contractor tool. Search by business name or license number (ECRA/ESA format). Confirm the license is current. ESA publishes how to verify a licensed electrical contractor as a dedicated consumer guide, because unlicensed work is a common complaint.[7]

Many HVAC companies do not hold their own electrical license; instead they subcontract the electrical scope to a partner LEC. That is fine as long as the subcontractor is named in the quote and you can verify their ECRA/ESA license separately.

Step 5: Skilled Trades Ontario 313A registry lookup

Refrigeration and air conditioning is a compulsory trade in Ontario, which means the work legally cannot be performed by an uncertified person. The relevant certificate of qualification is the 313A (Refrigeration and Air Conditioning Systems Mechanic), or the narrower 313D (Residential Air Conditioning Systems Mechanic).[4]

Go to skilledtradesontario.caand use the public Tradesperson search. Enter the technician's certificate number to confirm the credential is active. For a straightforward residential central AC install or heat pump, either a 313A or 313D is valid. For commercial refrigeration or complex multi-zone systems, you want a 313A.

The 313A is a four-year apprenticeship program (roughly 9,000 hours of on-the-job training plus in-school sessions) followed by a certifying examination. The 313D is a shorter program scoped to residential air conditioning only. Both credentials are renewable and require the holder to remain in good standing with Skilled Trades Ontario. A technician who completed the apprenticeship years ago but allowed their registration to lapse is technically no longer authorized to perform compulsory trade work, which is why checking current status matters as much as checking that the certificate ever existed.

Step 6: HRAI Contractor Locator for warranty-backed shops

HRAI, the Heating, Refrigeration and Air Conditioning Institute of Canada, runs a public Contractor Locator that lists member companies.[8] HRAI membership is voluntary and not a legal requirement, so a legitimate contractor may not appear there, but the locator is still useful for two reasons.

• Training and manufacturer relationships. HRAI members have access to ongoing technical training and typically carry direct dealer relationships with major manufacturers, which translates into faster warranty claims and parts availability.
• Consumer dispute resolution. HRAI maintains a consumer-focused portal with guidance on finding qualified contractors and a path for escalating complaints against member companies.[8]

Go to hrai.ca/contractor-locator and search by postal code or company name. Treat HRAI membership as a positive tiebreaker between two otherwise equal quotes, not as a pass-fail filter.

Step 7: WSIB clearance certificate

The Workplace Safety and Insurance Board issues a free clearance certificate that confirms a contractor is registered with WSIB and in good standing on their premium payments.[9] While WSIB compliance is technically a business-to-business concern, requesting a clearance certificate before work begins is a simple way to protect yourself from liability if a worker is injured on your property during the installation.

A reputable contractor will provide a clearance certificate on request, usually within a day. They can pull it directly from the WSIB online portal at no cost, and most professional shops keep a current clearance ready to send alongside their proof of liability insurance. If the contractor cannot or will not provide one, that is a clear red flag and often indicates a single-operator situation where the contractor is not maintaining proper WSIB coverage for subcontracted help. Keep the clearance certificate with your project paperwork; if anything goes wrong on site, it is your first line of documentation.

While you have the contractor on the phone about insurance, also ask for proof of commercial general liability (CGL) insurance, typically a minimum of $2 million. CGL is separate from WSIB and covers damage to your home and injury to household members during the job. Request a certificate of insurance naming you as a certificate holder, which is standard practice and costs the contractor nothing to provide.

Red flags that should stop the quote

• Refusal or delay in providing TSSA, 313A, or ECRA/ESA numbers in writing
• Door-to-door sales pressure to sign the same day, especially for rentals
• A quote that does not list permit fees separately, or a suggestion to skip permits to save money
• Request for full payment upfront, or a deposit larger than 25% to 30% of the total contract
• Equipment make, model, and serial number missing from the quote or contract
• No written labour warranty, or a labour warranty that is only verbal
• The business name on the quote does not match the name in the TSSA registry, or the company does not appear in the registry at all
• No proof of commercial general liability insurance (industry standard is a minimum of $2 million)
• The quote is 30% to 50% below the others you have received without a clear scope difference

Even one of these flags is reason to pause. Two or more is reason to walk away. The cost of walking away is a few days of your time; the cost of proceeding with the wrong contractor can run into tens of thousands of dollars in remediation, voided warranties, insurance disputes, and in the worst cases health and safety incidents. Ontario homeowners have the right to demand credentials and documentation from every contractor they deal with, and reputable shops welcome the scrutiny because it helps separate them from operators who cut corners on registration and permitting.

The cooling-off provisions of the Consumer Protection Act are another layer of protection. For most home service contracts signed in the home, Ontario law gives you a 10-day window to cancel without penalty, even after work has started.[10] The cancellation right exists because high-pressure door-to-door HVAC sales were a persistent problem in Ontario for years before regulations tightened. Treat the cooling-off period as your safety net, not your default plan: verify credentials up front so you never need to invoke it.

What to do if verification fails

If a contractor misrepresents their credentials, performs gas or electrical work without the required authorization, or pressures you into an unfair contract, Ontario has a clear complaint path for each regulator.

• Gas safety, TSSA registration, technician certificates. Report to TSSA through tssa.org. TSSA can audit the contractor, suspend or revoke registrations, and in serious cases pursue prosecution under Ontario Regulation 212/01.[2]
• Unlicensed electrical work. Report to the Electrical Safety Authority through esasafe.com. ESA has enforcement authority and publishes advisories naming non-compliant contractors.[6]
• Contract disputes, high-pressure sales, cancellation issues. Contact Consumer Protection Ontario through ontario.ca for home service contracts, including your 10-day cooling-off rights on in-person sales.[10]
• Trade certification misrepresentation. Skilled Trades Ontario handles complaints about unqualified individuals performing compulsory trade work.

Keep paper copies and email records of everything: the original quote, any revised quotes, the signed contract, photographs of the work in progress, and permit and inspection paperwork. Regulators need documentation to open a file and take action.

For a broader picture of permit requirements and inspections, see our Ontario building code guide.

Frequently Asked Questions