Deciding between AC repair or replacement usually comes down to two numbers, and you can run them yourself in about a minute. A repair quote in the middle of a July heat wave is the worst moment to invent a decision framework, so here is the one to bring with you. This guide gives you the two trade rules that settle most repair-or-replace calls, the typical cost of each common AC repair, the refrigerant factor that changes the math on older units, and the one question worth asking before any replacement, the same framework behind every air conditioner installation quote we issue.

The two rules of thumb that settle most cases

Two trade rules turn the repair-or-replace question into arithmetic, and they agree far more often than they conflict. Some professionals apply a stricter one-third threshold instead of one half; either way, the direction of the answer rarely changes once age enters the math. Run both rules before you approve any quote, and the choice between AC repair or replacement becomes a clear number rather than a guess.

Common trade rules of thumb, compiled August 2026; they frame the decision, and the on-site diagnosis prices it.

What each common AC repair typically costs

The type of failure drives the decision more than anything else, because a $300 capacitor and a $3,000 compressor sit on opposite sides of both rules. These are typical GTA market bands; the same symptom can trace to different failures, which is why a proper diagnosis comes before any decision.

Prices in Canadian dollars (CAD), typical GTA market ranges as of August 2026 including labour, subject to change; the exact figure comes from an on-site diagnosis.

The age framework

A central AC in Ontario typically lasts 12 to 15 years, well-maintained units longer, and age sets the default before any quote arrives. Under 8 years old, repair is the default and only a compressor-class failure should reopen the question; from 8 to 14, the two rules decide, and a second repair in the same summer counts as a vote to replace; at 15 and beyond, small cheap fixes can still make sense as a bridge, but any repair in the hundreds runs into the $5,000 rule immediately, and planning the replacement on your schedule beats doing it during a heat wave. The symptoms that mark a unit as nearing its end, the efficiency slide, the uneven rooms, the repeat calls, are their own topic, and our AC replacement timing guide covers them; this page stays the math. Age is the first lens for any AC repair or replacement decision, and it quietly points the answer before the technician even opens the panel.

The refrigerant factor on older units

If your AC is old enough to run on R-22 refrigerant, the decision usually makes itself: R-22 was phased out of production and import for servicing in Canada under the Montreal Protocol schedule, remaining supply is scarce and expensive, and any significant R-22 repair is money into a system whose lifeline has ended. Units from the last decade run R-410A, which remains fully serviceable; the industry is transitioning new equipment to next-generation refrigerants, but that transition is a reason to expect newer designs on the replacement side, not a reason to condemn a working R-410A unit. The data plate on your outdoor unit names the refrigerant; check it before your next service call so the quote conversation starts informed.

If you replace: the question worth asking first

Every AC replacement in Ontario should be priced beside one alternative: a cold-climate heat pump, which cools identically in summer, heats your home efficiently for most of the year, and is where the province’s rebate money sits, while a like-for-like AC swap earns essentially nothing. The full comparison and the current program amounts live in our guides to the best energy-efficient HVAC options in Ontario and government rebates for HVAC in Ontario; the short version is that after rebates, the heat pump can land closer to a plain AC’s price than most homeowners expect, and one honest caveat applies: for a gas-heated home with a newer furnace and a tight budget, the straightforward AC replacement remains a perfectly sound choice, and we install both without pushing either. That is why the smartest AC repair or replacement decisions in Peel Region weigh a heat pump beside a straight swap before anyone signs.

Repair vs replace, head to head

When the rules leave you in the borderline zone, this is the tiebreaker view: what each path actually buys you.

Tiebreaker factors compiled August 2026; they apply identically across Mississauga, Brampton, Etobicoke, Milton, Georgetown, Caledon, and Bolton.

AC repair or replacement: frequently asked questions

Should I repair or replace my 15 year old air conditioner?

At 15 years a central AC is at or past its typical Ontario lifespan, so replace it for any major repair and treat even mid-sized fixes with the $5,000 rule, which they usually fail at that age. The exception is a genuinely small repair, a capacitor or contactor, which can be a fair bridge while you plan the replacement on your own schedule.

What is the 50 per cent rule for AC replacement?

The 50 per cent rule says that when a repair quote reaches half the cost of a comparable new unit installed, replacement is the better investment, because you are paying repair money without gaining new-unit efficiency, warranty, or lifespan. Some professionals apply a stricter one-third threshold; on an aging unit the two versions rarely disagree on direction.

Is it worth repairing an AC compressor?

Rarely on a unit past 8 years old: a compressor replacement typically runs $1,800 to $3,000 CAD or more, which fails the 50 per cent rule against most new installations and fails the $5,000 rule at almost any age where compressors fail. On a young unit still under parts warranty, the math flips, so check the warranty before deciding.

How much does AC repair cost in Ontario?

Common repairs range from about $200 to $400 CAD for a capacitor or contactor up to $1,800 to $3,000 CAD or more for a compressor, with fan motors, leak repairs, and coils in between, as typical GTA market ranges in August 2026. The failure type drives the figure, which is why a written diagnosis comes before any repair-or-replace decision.

Should I replace my R-22 air conditioner?

Yes, at the next significant failure: R-22 was phased out of production and import for servicing in Canada, remaining supply is scarce and expensive, and major repair money into an R-22 system buys time on a refrigerant whose lifeline has ended. Check the data plate on your outdoor unit; if it names R-22, plan the replacement before the failure picks the date for you.

Should I replace my AC with a heat pump?

Price it beside the new AC every time: a cold-climate heat pump cools identically, adds efficient heating for most of the year, and holds Ontario’s current rebate money while a plain AC swap earns none. It is not automatic, a gas home with a newer furnace and a tight budget can reasonably choose the straightforward AC, but deciding without both quotes leaves money unexamined.

Final verdict

You know your AC needs replacement rather than repair when the quote reaches half a new unit’s price, when age times repair cost passes $5,000, when it is the second call of the summer, or when the data plate says R-22; everything else leans repair, especially under 10 years old. Bring both rules to your next quote, ask for the replacement price beside the repair price, and let a free estimate put real numbers on all three paths, repair, new AC, or heat pump, before a heat wave decides for you at air conditioner installation in Mississauga prices you never compared.

Sources and references

O. Reg. 463/10, Ozone Depleting Substances and Other Halocarbons, Government of Ontario
Natural Resources Canada, air conditioner efficiency and SEER2 ratings
Environment and Climate Change Canada, refrigerant phase-out under the Montreal Protocol
Skilled Trades Ontario, 313A and 313D refrigeration and air conditioning mechanic trades