AC and Furnace Replacement in Peoria, IL
In central Illinois you are buying two machines that live in the same closet and usually die in the same decade. The most expensive mistake here is replacing them one at a time.
What a new system costs in Peoria, installed
| System | Typical Peoria cost | Notes |
|---|---|---|
| AC only, existing furnace and ducts | $5,200-7,300 | like-for-like swap |
| AC + matched indoor coil | $6,400-8,600 | the common real answer |
| Furnace only, 80% efficiency | $3,900-6,200 | if the AC is still sound |
| Furnace only, 95%+ condensing | $5,400-9,100 | needs a new flue route |
| AC + furnace together, standard | $8,900-12,400 | saves $1,200-2,400 vs separately |
| AC + furnace, high-efficiency | $12,400-15,500 | two-stage, variable blower |
| Duct repair, sealing or rework | add $900-5,200 | the usual fix for a hot upstairs |
| Electrical or flue work | add $500-2,600 | older homes |
The one number nobody quotes you unasked
Your air conditioner and your furnace share an indoor coil, a blower, a duct system and an electrical connection. In most Peoria homes they were installed on the same day, which means they reach the end of their lives within a few years of each other.
If you replace them separately you pay twice for the same labour: pulling the old equipment, matching a new coil to an old blower, the permit, the commissioning visit. Doing both at once typically saves $1,200-2,400 - and it avoids the awkward middle state where a brand-new high-efficiency air conditioner is throttled by a twenty-year-old single-speed blower it was never designed to work with.
That is not an argument for always buying both. It is an argument for always asking for both numbers, because the gap is large enough to change the decision and it does not appear on a quote unless you request it.
If Upstairs Never Cools, the Box Is Not the Problem
This is the most common complaint in older Peoria homes and the most commonly mis-sold. A bigger air conditioner does not fix an upstairs that will not cool; it just makes the ground floor cold while the compressor short-cycles.
The real causes are ducts running through an unconditioned attic, undersized returns on the upper floor, or a trunk line that was extended when the house was. Fixing that is a $900-5,200 line, and it is the difference between a new system that solves the problem and a new system that just moves the money.
What a Peoria replacement quote usually does and does not cover
Included
- The equipment, refrigerant line connection, evacuation and charge
- Removal and disposal of the old furnace and condenser
- New thermostat and basic commissioning with measured airflow
- Manufacturer parts warranty and the contractor's labour warranty
- Standard flue connection on a like-for-like furnace swap
Not included
- Duct repair, sealing or resizing - the usual cause of an uncomfortable upstairs
- New flue or venting route, which a 95%+ condensing furnace often needs
- Electrical panel or circuit upgrades on older homes
- Condensate pump or drain rerouting in a basement install
- Permits and inspection, where the City of Peoria or the county requires them
Sizing matters more than the brand on the box
The most common mistake in residential HVAC is buying a system that is too big, because oversizing sounds like the safe choice. An oversized air conditioner cools the air quickly, shuts off, and never runs long enough to pull the humidity out. You get cold spots, a clammy house and a compressor that wears out early.
The fix is a load calculation - a Manual J or equivalent - based on your square footage, insulation, windows and orientation, not on what was there before. Ask whether the quote is based on one. A contractor who did the calculation will tell you happily; one who did not will change the subject to brands.
How to compare three quotes that look the same
- Fix the specification first: tons of capacity, SEER2, furnace AFUE, single-stage or two-stage, and what the indoor coil is. Then compare prices.
- Ask for the AC-only price and the AC-plus-furnace price on the same quote. That gap is the number this page exists for.
- Ask whether the size came from a load calculation or from matching the old unit.
- Ask what the quote assumes about your ducts and what happens if they are undersized. A stated allowance beats a surprise.
- Separate the manufacturer parts warranty from the contractor's labour warranty, and get both lengths in writing.
When replacing is the wrong answer
Worth saying plainly, because we have nothing to gain from you buying a system you do not need. An eight-year-old unit that needs a $300 capacitor and a clean is a repair. If someone opens with replacement on a system that age, ask them to price the repair as well and put both on paper.
Get a written quote for a new system
Tell us the square footage, roughly how old the AC and furnace are, and whether any rooms never get comfortable. We will match you with one vetted Peoria-area contractor who quotes in writing, including the both-at-once price. No charge for the match, no obligation, and we do not hand your number to four companies who will all call you.
Or call (309) 485-5762
Common questions
Should I really replace the furnace at the same time?
Ask for both numbers and decide with them in front of you. If the furnace is within a few years of the AC's age, doing both together usually saves $1,200-2,400 and avoids pairing new equipment with an old blower. If the furnace is genuinely much newer, it is not worth it.
Why is my upstairs still hot with a new air conditioner?
Almost always ducts, not capacity. Ducts in an unconditioned attic, or undersized returns upstairs, cap how much cool air can actually get there. A bigger unit makes downstairs colder and upstairs no better.
Is a 95% condensing furnace worth the extra?
In central Illinois the heating season is long enough that it usually pays back, but it needs a different flue route and a condensate drain, which is why the install cost jumps. Get it quoted both ways.
How long does a replacement take?
AC alone is usually one day. AC and furnace together is one to two days. Duct rework adds a day or more depending on access.
Why does the range go from $5,200 to over $15,000?
Because it covers a basic like-for-like AC swap at one end and a high-efficiency furnace-and-AC pair at the other. The table above shows which row you are in.