How Much Does a New Central AC Cost by Square Footage?
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 $7,669 and $18,415, 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: $7,669-$14,580
- 1,200-1,500 sq ft home, usually around 2.5-3 tons: $8,157-$14,976
- 1,500-2,000 sq ft home, usually around 3-3.5 tons: $8,944-$16,558
- 2,000-2,500 sq ft home, usually around 3.5-4 tons: $9,600-$16,752
- 2,500-3,000 sq ft home, usually around 4-5 tons: $10,229-$18,415
How Do You Estimate AC Cost From Your Home's Square Footage?
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 below ground 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.
What Makes the Price Go Up or Down?
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. In 2025, the U.S. Department of Energy also changed the refrigerant requirement to A2L refrigerant, which all new systems must now use.
- 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.
Should You Replace Your AC and Furnace at the Same Time?
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.
Is a Bigger AC Always Better?
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.
Repair or Replace? When New AC Pricing Wins
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
Quick AC Cost Estimator
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
How Does Trouble Free Quote a New AC?
At Trouble Free Heating, Cooling & Plumbing, we do not believe in one-size-fits-all AC quotes.
Every home is different. Every family is different. Every budget is different.
That is why we start with a careful in-home inspection. We look at your conditioned square footage, your current AC system, your ductwork, your electrical setup, your thermostat needs, and the way your home is actually cooling.
Then we explain what we find in plain English.
From there, we give you clear options. You may want the most affordable reliable system. You may want better energy savings. You may want improved comfort, better indoor air, financing options, or a system built for the long term.
Our job is not to pressure you.
Our job is to help you understand your choices, answer your questions, and help you choose the option that makes the most sense for your home, your family, your comfort, and your budget.
Once you choose the right option, we give you one clear installed price. Your quote 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. No confusing guesswork.
Just a clear inspection, honest options, and a recommendation you can feel good about.
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.