How to Become an HVAC Apprentice in Ontario

The path in one paragraph

An HVAC apprenticeship in Ontario is an employer-first path into the 313A trade — Refrigeration and Air Conditioning Systems Mechanic, the full-ticket licence for refrigeration and combined heating-cooling systems. Get hired by a mechanical or refrigeration contractor willing to sponsor you, register the training agreement with Skilled Trades Ontario, then work about five years of paid on-the-job hours (8,280 of them) interleaved with three classroom levels (720 hours), while picking up the TSSA gas licence and ODP certificate most employers expect. Pass the certifying exam, earn the Certificate of Qualification with its Red Seal endorsement, and you can work the trade anywhere in Canada.

First: the licence structure matters

Ontario's HVAC world runs on three separate tickets, and beginners mix them up. Get this right before you plan:

• 313A — Refrigeration and Air Conditioning Systems Mechanic. The full trade. Compulsory in Ontario, Red Seal-endorsed, 9,000 hours total (8,280 on-the-job plus 720 in-school, three levels) over about five years. With it you can install, service, and repair refrigeration and combined heating-cooling systems in residential, industrial, commercial, and institutional settings. This guide walks the 313A path.
• 313D — Residential Air Conditioning Systems Mechanic. The restricted route: roughly half the hours (about 4,500 total) and you are limited to residential work — single-family dwellings, systems under 240V single-phase, 60-amp branch circuits, and about five tons of cooling capacity. Faster in, narrower career.
• TSSA gas technician (G3 / G2 / G1). Separate licence, separate authority (the Technical Standards and Safety Authority). G3 is the supervised entry level, G2 (up to 400,000 BTUH) is the standard most HVAC jobs require, and G1 removes the ceiling. It is a big enough topic to have its own guide — but know from day one that your sponsor will care about it.

Plus the refrigerant-handling certificate: the Ozone Depletion Prevention (ODP) card, which Ontario employers list right alongside the trade certificate in job postings. Treat it as mandatory for hireability.

Step 1: Meet the entrance requirements

Every Ontario trade carries a published minimum education standard, and Skilled Trades Ontario states the current one on the 313A trade page — check it before you apply, since published minimums change. Treat the minimum as a floor: the classroom blocks run on applied trade mathematics, psychrometrics, heat load calculations, and electrical and electronic fundamentals. Apprentices who arrive with solid math fail out less often. If yours is rusty, upgrading first is cheaper than repeating a level.

Step 2: Find a sponsoring employer and register the agreement

This is the step that starts the clock. Your hours only count once a registered training agreement ties you to a sponsoring employer:

1. Get hired by a contractor willing to sponsor you. Residential HVAC shops, commercial mechanical contractors, refrigeration service companies (supermarket racks, walk-ins), building maintenance departments, and union locals all take apprentices. UA Local 787 covers refrigeration mechanics in the GTA and posts apprenticeship intakes periodically. You are selling yourself as a reliable first-year who shows up and can do math — not as a mechanic.
2. Register the training agreement with Skilled Trades Ontario. Your sponsor registers you; the agreement is what makes your on-the-job hours official. Skilled Trades Ontario issues the Certificate of Apprenticeship when the program is complete and administers the certifying exam.
3. Work under qualified supervision. Your trainer or journeyperson signs the relevant sections of the trade's training standard as you demonstrate each competency. The logbook is the record — keep it current.

A shortcut worth knowing: college pre-employment HVAC programs (a few months, Level-1 material plus tool skills) teach you the first classroom block and basic tool handling. A pre-employment certificate does not replace a sponsor, but it answers the question every contractor asks: "will this person slow my journeyperson down?" The sponsor hunt is a job search in every sense: our job hunting guide walks through Job Bank, Canadian resume conventions, and the NOC codes you will use on applications.

Step 3: Work through the five-year program

The official numbers, straight from Skilled Trades Ontario: 8,280 hours of on-the-job work experience plus 720 hours of in-school training, for 9,000 hours total over about five years. The classroom runs in three levels covering workplace health and safety, the mechanical cooling cycle, electrical and electronic control systems, pipe joining and brazing, psychrometrics, heat load calculations, and system start-up procedures. Depending on the training delivery agency, school comes as block release (full-time for a set number of weeks), day release (one day a week), night school, or online and correspondence formats.

Two notes that matter. First, each level ends with exams you must pass to advance — the hours alone do not promote you. Second, the wage schedule is regulatory, not customary: O. Reg. 75/05 sets apprentice minimums at 40, 50, 60, 70, then 80 per cent of the average journeyperson wage at your employer across the five apprenticeship periods. For scale, recent Ontario postings for certified 313A mechanics run roughly $33 to $46 per hour (school boards and municipalities publish their bands) — first-year apprentice pay sits near 40 per cent of the going journeyperson rate at your company and climbs from there.

The apprentice pay scale, period by period

People search for a single starting wage. Ontario does not work that way. The province sets a pay scale as a share of what journeypersons earn, and your dollar wage depends on the shop that sponsors you.

Ontario Regulation 75/05 says a 313A apprentice must be paid at least these shares of the average journeyperson wage at their own employer:

Two things change the numbers in real life.

First, the $40 figure in the table is an example, not a provincial rate. Job Bank reports Ontario wages for air conditioning and refrigeration mechanics at a low of $21.63 per hour, a median of $38.46, and a high of $58.00, with wages updated on December 3, 2024. A sponsor whose journeypersons sit near that median produces a different scale from a high-paying commercial shop. Ask what the journeypersons at that shop earn. The answer sets your pay for all five periods.

Second, there is a floor under the whole scale. Ontario's general minimum wage is $17.95 per hour from October 1, 2026, and apprentice pay cannot sit below it. At a low-paying shop, the first period often pays the minimum wage rather than 40% of a small journeyperson rate. The percentage starts to bite once you reach the second and third periods.

Employers can pay more than the minimum scale, and some do to keep good apprentices. Union shops publish their own scales in their collective agreements, which can run ahead of the regulation. Read any offer against the table above. If a sponsor offers less than the scale for your period, that is a legal problem, not a negotiation.

Step 4: Stack the adjacent tickets

Plan these alongside the apprenticeship, not after it:

• TSSA gas technician. The G3→G2 progression is the standard pairing with 313A — most HVAC service jobs expect a G2. Start the G3 course once you are settled with your sponsor.
• ODP certificate. Get it before you start applying; it is a first-pass hiring filter.
• G driver's licence. Nearly every posting requires a valid Ontario G licence with a clean record — the job is a van job.

Our heat pump guide covers the equipment side if you want to understand the machines before you train on them.

Step 5: Pay for the technical training

Classroom blocks cost money — a few thousand dollars per school level depending on the institution — but you are earning a wage between blocks, and the funding picture is straightforward:

• The Canada Apprentice Loan covers up to $4,000 per period of technical training, interest-free, with no payments due until you finish or leave the program. Available everywhere except Quebec.
• Employment Insurance covers apprentices while they attend full-time technical training. Apply before your school block starts — processing takes time.
• Skip the federal apprentice grants: the Apprenticeship Incentive Grant ($1,000 per level) and the Apprenticeship Completion Grant ($2,000) closed on March 31, 2025. Older guides and forums still describe them as live; they are not.

Step 6: Write the exam and keep the certificate current

With the hours and school levels done, you write the certifying exam. Passing earns the Certificate of Qualification from Skilled Trades Ontario — and because 313A is an Interprovincial Red Seal trade, the exam carries the Red Seal endorsement, the national stamp that lets you work the trade anywhere in Canada without re-certifying. Our Red Seal guide explains the endorsement mechanics, exam format, and the trade-qualifier route for experienced workers.

One ongoing obligation: Skilled Trades Ontario states that a Certificate of Qualification in this trade must be renewed to stay valid. And if you ever want the business side — vans, service contracts, hiring — our trades comparison guide walks through the startup shape for HVAC companies.

Where to train: HVAC schools in Ontario

Ready for the in-school portion? Our directory of HVAC training programs in Ontario lists approved providers — public colleges, union training centres, and pre-apprenticeship programs — every one verified against the provincial apprenticeship authority.

Related guides

• Plumbing vs electrician vs HVAC business in Canada — the startup shape for an HVAC company: training time, compulsory footprint, and journeyperson pay benchmarks compared side by side.
• How to get your Red Seal endorsement in Canada — the certifying exam carries the Red Seal endorsement: routes, format, fees, and the national portability it buys.
• How to become a gas technician in Ontario — the G3→G2 licence most HVAC employers expect alongside the 313A trade certificate: the TSSA track, hours, and exam format.
• How to Start an HVAC Business in Canada — the business side once you are certified: the refrigeration, gas, and ODP certification stack, registration, permits, and flat-rate install pricing.

Sources

• Skilled Trades Ontario, Refrigeration and Air Conditioning Systems Mechanic trade page (compulsory status, 9,000-hour program, 8,280/720 split, three in-school levels, renewal requirement, Red Seal status)
• O. Reg. 75/05 (apprentice wage schedule — 40/50/60/70/80% across five periods) —
• Job Bank, NOC 72402 — prevailing wages for air conditioning and refrigeration mechanics —
• Job Bank, wages in Ontario for air conditioning and refrigeration mechanics (low $21.63, median $38.46, high $58.00 per hour; wages updated December 3, 2024)
• Ontario, Your Guide to the Employment Standards Act — minimum wage (general rate $17.95 per hour from October 1, 2026) —
• Job Bank, NOC 72402 — job requirements, including compulsory-certification provinces and the 3–5 year apprenticeship —
• Red Seal program (red-seal.ca)