New AC Cost by Home Size in Central Illinois

If your air conditioner is getting older, breaking down, or struggling to keep up in the summer heat, the first question most homeowners ask is simple: how much does a new central AC unit cost? For many central Illinois homes, a new central air conditioner installed typically falls somewhere between $4,000 and $10,000+, depending on home size, system size, equipment efficiency, ductwork condition, electrical needs, and installation requirements. The fastest way to start ballparking your number is by home size.

• 1,000-1,200 sq ft home, usually around 2-2.5 tons: $4,000-$5,500
• 1,200-1,500 sq ft home, usually around 2.5-3 tons: $4,500-$6,500
• 1,500-2,000 sq ft home, usually around 3-3.5 tons: $5,500-$7,800
• 2,000-2,500 sq ft home, usually around 3.5-4.5 tons: $6,500-$9,200
• 2,500-3,000 sq ft home, usually around 4.5-5 tons: $7,500-$10,500

These are typical installed price ranges for many central Illinois homes in 2026. Your final price depends on your home layout, ductwork, electrical, equipment match, refrigerant line condition, thermostat needs, and the actual installation requirements. A proper estimate should include more than just replacing the outdoor unit. It should account for the outdoor condenser, indoor coil, refrigerant lines, thermostat, permits when required, old-system removal, and making sure the system is properly sized for your home. Want a tighter quote for your actual home? Call Trouble Free Heating, Cooling & Plumbing at (309) 347-5309 or request a free in-home estimate.

Here is a simple way to get a rough starting point. Step 1: Find your conditioned square footage. This is the heated and cooled part of your home, not the garage, unfinished basement, or storage areas. Step 2: Divide the square footage by roughly 500 to 600 to estimate general AC tonnage. For example, a 1,800 sq ft home may land around a 3 to 3.5 ton system. Step 3: Multiply the rough tonnage by about $1,800 to $2,400 per ton for a general installed price range in central Illinois. Using that math, a 1,800 sq ft home may fall somewhere around $5,400 to $8,400 depending on the final system, ductwork, and installation details. This is only a starting point. Final sizing should not be based on square footage alone. A proper quote should include a Manual J load calculation or equivalent sizing review, because windows, insulation, ceiling height, shade, ductwork, and home layout all affect the right system size. See our companion guide on what size AC unit you actually need.

Several factors can move your AC replacement price higher or lower.

• SEER2 efficiency rating: Minimum efficiency standards changed in 2023, and higher-efficiency systems usually cost more upfront. According to the U.S. Department of Energy, today's best central AC units use 30 to 50% less energy to produce the same cooling as units made in the mid-1970s, so moving into the 15-16 SEER2 range can improve comfort and reduce energy use compared to an older system.
• Ductwork condition: Leaky, undersized, damaged, or poorly designed ductwork can make a new AC system perform badly even if the equipment itself is good. Duct repairs or modifications may add cost, but they can also make a major difference in comfort and efficiency.
• Electrical: Some older homes in Pekin, Peoria, and surrounding central Illinois communities may need electrical updates, a dedicated circuit, disconnect work, or panel-related improvements before a new system can be installed properly.
• Brand, equipment level, and warranty: Higher-end equipment, better warranties, variable-speed options, and premium comfort features may cost more upfront, but they can also improve comfort, noise level, humidity control, and long-term peace of mind.
• Heat pump vs. straight AC: A heat pump can cool your home like a central AC but also provide heating. It may cost more than a standard AC system, but it can be a strong option for some homeowners depending on utility costs, existing equipment, and comfort goals. See what a heat pump is and whether it pays off.

If your furnace is older, it may be worth pricing the AC and furnace replacement together instead of replacing the AC now and coming back later for the furnace. Many central Illinois homes have systems where the outdoor AC, indoor coil, blower, furnace, and thermostat all work together. When one part is replaced, the rest of the system still has to be compatible. Replacing both at the same time can sometimes reduce duplicated labor, improve system matching, simplify warranty coverage, and lower the total project cost compared to doing the work in two separate visits. Trouble Free Heating, Cooling & Plumbing may offer additional savings on qualifying furnace upgrades when completed with a new AC installation. Ask about current AC and furnace replacement specials when you schedule your estimate.

No. This is one of the easiest ways homeowners get burned. An oversized AC can cool the home too quickly, shut off before pulling enough humidity out of the air, and short-cycle all summer long. That can make the house feel damp or clammy, wear out the compressor faster, and still leave you with high electric bills. An undersized AC has the opposite problem. It may run constantly on hot July afternoons and still struggle to keep the home comfortable. The right answer is not guessing from the old unit's nameplate. The right answer is a proper sizing review based on the home.

Replacement may make more sense when:

• Your current AC is over 10 years old
• The repair estimate is expensive
• The system uses outdated refrigerant
• The unit has had repeated breakdowns
• Your energy bills keep climbing
• Some rooms are too hot while others are too cold
• The repair cost is getting close to the cost of replacement

As a general rule, if an older AC system needs a major repair and that repair is within roughly 40% of a new installation, it is worth comparing the repair against replacement. Repairing an old system may get it running again, but replacement gives you a new system, new warranty, better efficiency, and a fresh start. Our AC repair cost guide and AC repair service page break down the repair-vs-replace math by component.

Want a rough starting point before scheduling an appointment? Tell us a few quick details and we will help you understand the likely range before you spend money on the wrong system.

• Your home size
• Whether you need AC only or AC plus furnace
• The age of your current system
• Whether your ductwork is in good shape, unknown, or needs work
• Whether you are interested in financing options

Get My AC Replacement Estimate

Trouble Free Heating, Cooling & Plumbing comes to your home, reviews your conditioned square footage, checks your existing system, looks at your ductwork and electrical, and helps determine the right system size for your home. Then we give you one clear installed price that includes the equipment, installation, thermostat needs, refrigerant work, permits when required, and old-system disposal. No hourly games. No surprise add-ons on installation day. Just a clear recommendation based on your home and your comfort needs. We install new air conditioning systems across Pekin, Peoria, Morton, Washington, Canton, East Peoria, Tremont, and surrounding central Illinois communities. Wondering what a new AC unit would cost for your home? To keep your home trouble-free, call (309) 347-5309 or request your free in-home AC replacement estimate today.

Request My Free AC Estimate