Furnace replacement in Wheaton, IL
The short answer
FortHouse Heating & Cooling replaces and installs furnaces in Wheaton, IL for $5,000–$9,000 installed. An 80% AFUE furnace costs $5,000–$7,000. A 95%+ condensing furnace is $5,500–$9,000 with its sealed PVC venting, and that tier includes the quieter two-stage and modulating models that suit a larger house. A standard swap takes one day. The City of Wheaton requires a permit and sizing by ACCA Manual J, so we run the load calculation, prepare the submittal, and book the final inspection. The estimate is free and written before anything is removed.
Written by Jenna Fortman, Owner of FortHouse Heating & Cooling. Installed by EPA 608 and NATE-certified technicians.
Which new furnace fits your Wheaton house?
Upstairs runs colder than downstairs
Price a two-stage or modulating furnace. Long, low cycles keep air moving through both floors, and the Manual J shows each room's heat loss before anyone promises what the ductwork can do.
Bedrooms sit above the furnace room
A variable-speed blower ramps up gradually instead of starting at full speed, so the furnace is heard less at night.
The water heater shares the chimney
A 95% furnace leaves the water heater venting alone, and the City requires that flue lined; the liner is its own line on the quote.
You plan to sell within a few years
An 80% furnace at $5,000–$7,000 keeps the up-front cost lowest and reuses the chimney flue. From December 18, 2028, most new gas furnaces must be 95%.
You want the 2026 Nicor Gas rebate
Install an eligible 95%+ furnace by December 31, 2026 and apply within 90 days: $150 at 95% AFUE, $225 at 97%.
How much does a new furnace cost in Wheaton, IL?
| Furnace | AFUE | Installed | How it heats a larger house |
|---|---|---|---|
| Single-stage, standard | 80% | $5,000–$7,000 | Full fire or off, so upstairs rooms can swing between cycles. Vents up the existing chimney flue |
| Single-stage, condensing | 95%+ | $5,500–$9,000 | The same on-off pattern, with sealed PVC to an outside wall, burning roughly a sixth less gas than an 80% furnace for the same heat |
| Two-stage, condensing | 95%+ | $5,500–$9,000 | Runs on its low stage most of the winter: longer, quieter cycles and more even rooms on both floors |
| Modulating, variable-speed | 95%+ | $5,500–$9,000 | Adjusts its flame in small steps to match the heat loss; the steadiest, quietest choice for a big house |
| Duct changes | — | From $550 | Only if the old runs can't carry the new blower's air. Wheaton's code requires any replaced duct to be sealed |
Every condensing option sits in the same $5,500–$9,000 range; the staging, the blower and how far the vent pipe has to travel decide where yours lands, and the written estimate lays the options side by side. Eligible 95%+ furnaces installed by December 31, 2026 can also qualify for a $150–$225 Nicor Gas rebate; the terms are in the questions below.
Replace the Wheaton furnace now, or repair it once more?
FortHouse Heating & Cooling's rule of thumb for Wheaton furnaces: multiply the furnace's age by the repair quote. Under about $5,000, a repair usually earns its keep; past it, the money is better spent on a new furnace. No single repair should cost more than half of a replacement, and a cracked heat exchanger ends the question. Replacing on your own schedule buys something an emergency call can't: time to choose the staging, settle the City permit and, through December 31, 2026, claim the Nicor rebate. If it's a repair after all, Wheaton furnace repair starts at $119.
Repair is likely right when
- The furnace is under about 12 and this is its first real repair
- The fault is an ignitor, flame sensor, capacitor or pressure switch
- Combustion readings are clean and every floor keeps up
Replacement usually wins when
- It's past 15 and the quote is for an inducer, blower motor or control board
- Upstairs has never kept up, so a repair only buys more of the same
- There's soot, a cracked heat exchanger, or carbon monoxide at the flue
| Furnace age | Repair quote | Age × cost | Verdict |
|---|---|---|---|
| 6 years | $380 pressure switch | 2,280 | Repair |
| 15 years | $310 ignitor | 4,650 | Close: price both |
| 19 years | $650 inducer motor | 12,350 | Replace |
| 23 years | $900 control board | 20,700 | Replace |
How does a furnace installation in Wheaton work, from estimate to final inspection?
Estimate visit
Room-by-room walkthrough
We measure the house for the Manual J the City requires, check the chimney and water heater, the 30-inch service space and a vent route, and price single-stage, two-stage and modulating options together.
Before install day
Written quote, line by line
The furnace model with its AFUE and BTU rating, the venting, any flue liner or duct work, and the thermostat, each priced on its own line.
City of Wheaton submittal
We file the permit with the furnace's specifications, its installation manual and, for an 80% furnace, the combustion-air worksheet.
Install day
Old furnace removed
We close the gas valve, kill power at the furnace switch, cap the old vent, and haul the old furnace away at no charge.
New furnace set to code
Gas line, venting, condensate drain and duct connections finished, with any replaced duct sealed as the City's energy code requires.
Startup readings and thermostat
The combustion analyzer's numbers are written onto your install record, and the programmable thermostat Wheaton requires is set to your schedule.
After
Final inspection and rebate
We book the City's final inspection, with the Manual J ready if the inspector asks, and hand you the model and AFUE details Nicor's rebate form needs.
Details from FortHouse furnace installs
Bigger houses, a detailed City code: what changes a Wheaton furnace job?
Bigger homes than most of Illinois
Wheaton's homes are larger than the Illinois norm. In the Census Bureau's 2020–2024 survey, 6,999 of the city's 20,359 homes (34%) have four or more bedrooms, the median home has 6.4 rooms against 5.6 statewide, and the median owner-occupied home is valued at $455,700, about 1.7 times the Illinois figure. Seven in ten households own their home. In a two-story house that size, how evenly the furnace heats matters as much as its efficiency rating, which is why FortHouse Heating & Cooling prices a two-stage or modulating model next to a single-stage one.
What the City asks for
The City of Wheaton's furnace guideline works from the 2024 International Residential, Fuel Gas and Mechanical Codes. A replacement application lists the new furnace's brand, efficiency and BTU rating with the manufacturer's installation instructions, and a standard-efficiency gas furnace adds a combustion-air worksheet. The equipment must be sized by an ACCA Manual J load calculation, which the inspector can ask to see, and the furnace needs 30 inches of clear working space in front of its controls. A finished basement built snugly around the old unit can change the plan, so we check that clearance on the estimate visit.
The orphaned flue, and 2028
Trading an 80% furnace for a 95% one moves the furnace's exhaust out of the chimney, and a gas water heater left venting there alone can draft poorly in a flue sized for two appliances. Wheaton requires that orphaned flue to be lined and checks it at final inspection, so the liner belongs on the quote from the start. The choice has a deadline, too: under a Department of Energy rule finalized in 2023, most new gas furnaces must reach 95% AFUE from December 18, 2028, so the 80% option is in its last few years on the market.
Questions Wheaton homeowners ask
How much does a new furnace cost in Wheaton, IL?
FortHouse Heating & Cooling installs a new furnace in Wheaton for $5,000–$9,000. An 80% AFUE furnace costs $5,000–$7,000 and keeps using the chimney flue; a 95%+ condensing furnace, whether single-stage, two-stage or modulating, is $5,500–$9,000 with its PVC venting. Duct changes start at $550, and a flue liner is priced on its own line when the water heater needs one. The written estimate is free.
Do I need a permit to replace a furnace in Wheaton?
Yes, inside city limits. FortHouse Heating & Cooling files the City of Wheaton permit, which asks for the furnace's brand, efficiency, BTU rating and installation instructions, plus a combustion-air worksheet for an 80% furnace, and books the final inspection that closes the job. An unincorporated address with a Wheaton mailing address is permitted through DuPage County instead.
Is a two-stage or modulating furnace worth it in a large Wheaton home?
Often, in a two-story house with four bedrooms. A single-stage furnace fires at full output every time, so it heats in short bursts. A two-stage furnace spends most of the winter on its low stage, and a modulating one adjusts in small steps, which means longer, quieter cycles and steadier temperatures from floor to floor. FortHouse Heating & Cooling quotes all three within its $5,500–$9,000 range for 95%+ furnaces, side by side on the estimate.
What is an orphaned flue, and why does Wheaton require a liner?
When a new 95% furnace vents through PVC, the gas water heater is left alone in a chimney flue built for two appliances. Its smaller, cooler exhaust may not draft well there, and the condensation it leaves behind wears on masonry. The City of Wheaton requires that flue to be lined and verifies it at final inspection, so FortHouse Heating & Cooling prices the liner up front.
Why does the City of Wheaton ask for a Manual J calculation?
FortHouse Heating & Cooling runs an ACCA Manual J on every Wheaton replacement because the City of Wheaton's code requires heating equipment to be sized from the house's calculated heat loss, not the old furnace's nameplate, and the inspector may ask to see the numbers. In Wheaton houses that have been finished, added onto or re-insulated since the last furnace went in, the right size is often not the old one.
How long does a furnace replacement take in Wheaton?
One working day for a standard swap: FortHouse Heating & Cooling removes the old furnace, installs the new one and runs the startup test on the same visit. A new PVC vent route, a flue liner or duct changes can add time, which the written quote spells out. The City's final inspection is booked after the install.
Can a Wheaton furnace installed this year still get a Nicor Gas rebate?
Yes, if it's installed by December 31, 2026 on a qualifying Nicor Gas account. Nicor pays $150 for an eligible 95% AFUE furnace and $225 at 97%, or $200 and $275 if a qualifying smart thermostat is claimed with it. Apply within 90 days of the install, and by January 31, 2027 at the latest; FortHouse Heating & Cooling hands over the model and AFUE details the form needs. The federal 25C tax credit ended for equipment installed after 2025.
My Wheaton home heats with electricity. Is a heat pump an option?
Yes. About 13% of Wheaton households, 2,626 in the Census Bureau's 2020–2024 survey, heat with electricity rather than gas. FortHouse Heating & Cooling installs heat pumps for $5,500–$10,000, and the same outdoor unit cools the house in summer. FortHouse's heat pump installation page compares the options.
What warranty and financing come with a new furnace?
FortHouse Heating & Cooling installations carry a 10-year parts warranty and a 1-year labor warranty, and financing is available for homeowners who prefer monthly payments. The company is family-owned, run by owner Jenna Fortman, and based in Plainfield; about FortHouse Heating & Cooling.
Sources
Prices are FortHouse's published installed ranges for Wheaton, and every quote is written after a walkthrough of the house. Code requirements come from the City of Wheaton's residential furnace guideline; housing figures from the Census Bureau's 2020–2024 ACS estimates.
Plan a new Wheaton furnace: free written estimate, permit handled
After hours? Call (630) 318-6246, answered 24/7.