Cooling that beats a 40° humidex
Cooling a Burlington, Oakville or Hamilton house costs $4,500–$5,800 for a 16 SEER2 central air conditioner, $5,500–$7,000 for a two-stage 3-ton system, or $4,000–$6,000 for a single-zone ductless — and the right size is set by lake-effect humidity as much as heat. Most repairs run $150–$800 and finish in one visit.
Cooling covers central air conditioning, ductless mini-splits, heat pumps in cooling mode, and the fan coils in downtown Burlington and Bronte condos. The design problem here is the lake: a July afternoon in Roseland or Old Oakville is wetter than the same temperature in Milton or Georgetown, so the system that wins is the one that runs long enough to wring moisture out, not the one that cools fastest.
Oversizing is the most common cooling mistake in Halton. A builder-grade 3-ton condenser on a modest Orchard or River Oaks two-storey chills the air in minutes and shuts off before the coil has dehumidified anything — the cold-and-clammy house (why it's humid with the AC on). We size by load calculation — glass, orientation, insulation, duct capacity — and near the lake the answer is often a smaller two-stage unit that runs longer.
Failures follow the equipment era. The 2000s single-stage units in Alton Village and Waterdown lose run capacitors and contactors first, then condenser fan motors; 1990s Tyandaga and Glen Abbey units run R-22, so a leak there is a replacement conversation, not a top-up. Condensers beside the QEW and 403 corrode faster from winter road-salt spray and earn their spring coil rinse.
A repair visit starts with the $90–$150 diagnostic — pressures with superheat and subcooling, capacitor microfarads, contactor faces, condensate drain. A capacitor or contactor is $150–$350, a fan motor $300–$700, a leak repair and recharge $300–$800+. If the furnace is also near its end, replacing both at once runs $7,500–$11,500 and saves roughly a thousand dollars over separate jobs (replace furnace and AC together?); for duct-less brick in Westdale and Dundas, ductless runs $4,000–$6,000 a zone or $9,000–$14,000 for three.
Book cooling work when
- The house hits the set temperature but feels damp — a sizing or fan-setting problem, not refrigerant
- Ice on the suction line or indoor coil — shut cooling off and let it thaw before the compressor pays for it
- The condenser hums but the fan doesn't spin — usually a capacitor
- The unit is past 12 years, runs R-22, and needs its second top-up
- Upstairs bedrooms are hot every July while the main floor holds
How it works
Glass, orientation, returns and static pressure measured; central priced against ductless where it's close — the usual case is a 1950s Aldershot bungalow with undersized returns.
Equipment options with SEER2 ratings and the operating-cost gap between tiers, in writing, with the Ontario minimum of 13.4 SEER2 as the floor — never the target.
Pad levelled, line set pressure-tested with nitrogen, vacuum pulled, charge weighed in, airflow verified at full load — one day for central. Book an assessment.
Brands: We install and service Lennox, Carrier, Goodman, Daikin, Mitsubishi and every other major cooling brand.
Common questions
Why is my AC running but not cooling?
In order of likelihood: a clogged filter starving airflow, a dead capacitor ($150–$350 to fix), a refrigerant leak, or an iced coil. Switch cooling off, leave the fan running to thaw it, change the filter, and call if it repeats — a frozen system can take the compressor with it. The AC not cooling guide walks through each cause.
Central AC or ductless?
With sound existing ducts, central wins on cost per ton and whole-home dehumidification. With no ducts — radiator-heated brick in Westdale or Kerr Village — or one stubborn room over a garage in Millcroft, ductless wins. When it's close we quote both; see cooling in Oakville for how lakeshore homes usually land.
How long does AC installation take?
A like-for-like central replacement is one working day. Add time when the line set is the wrong size or can't be flushed clean for a new R-32 or R-454B unit, when the electrical needs a new disconnect, or when the condenser must move to meet setback rules. Ductless is about a day for one or two heads.
What SEER2 rating should I buy?
The legal floor for a new split system is 13.4 SEER2; 16 SEER2 is where most Halton homes land because the step up costs little over the unit's life. Above that, two-stage and variable-speed earn their premium on humidity control more than on hydro savings — long, slow runs are what a lakeshore July needs.
Should I consider a heat pump instead?
Often, yes. A cold-climate heat pump cools identically to an AC of the same tonnage, heats most of the winter, and qualifies for Ontario rebates of up to $7,500 that a straight AC never sees. It costs more up front, so it wins only when it also displaces gas heating. Heat pump vs air conditioner lays out both.