# Ontario Central AC Guide: Manual J Sizing, SEER2 Ratings & 2026 Installation Costs **URL:** \ **Category:** Ontario\ **Created:** [April 26, 2026, 6:25pm UTC](https://home.renovation.reviews/t/ontario-central-ac-guide-manual-j-sizing-seer2-ratings-2026-installation-costs/46862 "2026-04-26T18:25:19Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![system](https://home.renovation.reviews/user_avatar/home.renovation.reviews/system/32/77_2.png) [@system](https://home.renovation.reviews/u/system)\ **Post date:** [April 26, 2026, 6:25pm UTC](https://home.renovation.reviews/t/ontario-central-ac-guide-manual-j-sizing-seer2-ratings-2026-installation-costs/46862/1 "2026-04-26T18:25:19Z")
Central air conditioning is standard in Ontario homes today. Whether replacing or installing new, here is a full 2026 guide. **Central AC vs Ductless Mini-Split** Central AC uses existing ductwork from one outdoor unit. Ductless mini-splits condition individual zones without ducts — ideal for homes without central ducting, for room additions, or targeted cooling upgrades. **Sizing: Manual J Required** Oversized AC short-cycles, fails to dehumidify properly, and wears faster. Undersized cannot handle peak summer days. Typical 2,000 sq ft Ontario home: 2.5-3 ton (30,000-36,000 BTU). Always demand a Manual J load calculation from your HVAC contractor. **SEER2 Efficiency** Canada mandates minimum SEER2 13.4 for new central AC. High-efficiency units: SEER2 18-22. Higher SEER2 reduces hydro bills under Ontario’s Time-of-Use pricing. **Installation Costs 2026** Central AC 2.5 ton, 16 SEER2: $3,500-$6,000 including permits and refrigerant. If air handler/coil also replaced: +$1,500-$3,500. Single-zone ductless: $3,000-$5,500 installed. **Permits** ESA electrical permit required. Refrigerant handling requires certified technician. Verify contractor licences and insurance. Find Ontario HVAC contractors and discuss AC options at home.renovation.reviews.