How Much Does a New AC Unit Cost in 2026?
A new central air conditioning system costs $4,000-$10,000 installed in central Illinois. Most homeowners pay $5,500-$7,500 for a quality 16 SEER2 unit with professional installation. The final price depends on your home's size, the efficiency rating you choose, and whether your existing ductwork and electrical need modifications.
What Drives the Cost of a New AC System?
- SEER2 rating: A 14.3 SEER2 (minimum legal) costs $4,000-$6,000. A 18-20 SEER2 runs $7,000-$10,000 but slashes electric bills.
- Home size: A 1,500 sq ft home needs a 2.5-3 ton unit. A 2,500 sq ft home needs 4-5 tons. Bigger unit = higher cost.
- Ductwork condition: Leaky or undersized ducts reduce efficiency by up to 30%. Duct repair or replacement adds $1,000-$3,000.
- Electrical upgrades: Older homes may need a dedicated circuit or panel upgrade.
What SEER2 Rating Should You Choose?
The minimum legal SEER2 in Illinois is 14.3. For central Illinois summers, a 16-18 SEER2 unit gives you the best balance of upfront cost and monthly savings. Going above 20 SEER2 offers diminishing returns unless you run your AC heavily from May through September. A regular AC tune-up keeps any unit running at peak efficiency.
When Is Full AC Replacement Worth It?
If your AC is over 10 years old and needs a major repair (compressor, coil, or refrigerant leak), replacement usually makes more financial sense. A unit still using R-22 refrigerant (phased out) is expensive to recharge and should be replaced. Check our AC repair cost guide to compare repair vs. replacement numbers for your situation.
How Does Trouble Free Handle AC Installations?
We start with a proper load calculation to size your system right. Our quote includes the outdoor unit, indoor coil, thermostat, refrigerant lines, electrical connections, permits, and old system disposal. One price, everything included. We handle AC installation across Peoria, Pekin, Morton, Washington, Canton, and surrounding areas. To keep your home trouble-free, call (309) 347-5309 or get a free estimate.