FurnaceTallyInput BTU, output BTU, and the gap nobody explains.

How much does a 80% AFUE furnace replacement cost in Naperville, IL?

An 80% AFUE furnace replacement in Naperville, IL
$4,142
reuses the existing metal flue — the cheapest like-for-like swap · typical range $3,270 – $5,668
Typical totalinstalled, 80 afue$4,142
Range you should see in bidsthree bids on the same scope normally land inside this$3,270 – $5,668
Labor portion40% of the job — this is the part that moves by city$1,657
Material portion60% — bought at national prices$2,485
Heating, Air Conditioning, and Refrigeration Mechanics and Installers pay near Napervilleabout $38/hr · Chicago-Naperville-Elgin, IL-IN metro$79,340/yr
U.S. mean for the same tradeSOC 49-9021$64,780/yr
Versus the national pricetrade pay here runs +22.5% against the U.S. mean+$342
Design temperatures91°F summer and -2°F winter at Chicago O’hare Airport — the two numbers a Manual J starts from, and the reason equipment sized for one city is wrong in another—

Notes

  • Where the number comes from. The national price for an 80% AFUE furnace replacement is $3,800 installed — gas furnace replacement pricing published for 2026. Labor is about 40% of that. Heating, Air Conditioning, and Refrigeration Mechanics and Installers near Naperville, IL average $79,340 a year against a U.S. mean of $64,780 — a factor of 1.225 — so the labor half is scaled by that and the material half is not. Source: BLS OEWS May 2025 for the Chicago-Naperville-Elgin, IL-IN metro area, SOC 49-9021.
  • Why the city matters, not just the state. Trade pay moves inside a state as much as it does between states. Crews do not commute across a state to bid a job, and materials ship at national prices either way — so a metro wage is the honest input here and a state average quietly rounds four different cities into one number.
  • Design temperatures. 91°F summer and -2°F winter at Chicago O’hare Airport — the two numbers a Manual J starts from, and the reason equipment sized for one city is wrong in another.
  • What is in the price: the furnace, removal and disposal of the old one, a new flue or vent kit, gas and electrical connections, a thermostat, permit and labor.
  • What is not: ductwork changes, a chimney liner where an 80% unit is orphaned by a water heater, and any return-air work the new blower needs. These are the lines that turn a $4,142 quote into a $5,177 invoice, so ask about each one before signing.
  • Use this as a bid check, not a quote. It prices an average job in average condition. Difficult access, the state of what is being replaced, the season, and a crew booked out three months all move the real number, and none of them are in a national average for the job.

an 80% AFUE furnace replacement in Naperville, IL

$4,142 is the typical number, and three bids on the same scope normally land between $3,270 and $5,668.

That is $342 more than the same job priced at the national average.

Why the city changes the number

About 40% of this job is labor — $1,657 of the $4,142 above. Labor is the only part that moves locally; a bundle of material costs what it costs wherever it is nailed down.

Heating, Air Conditioning, and Refrigeration Mechanics and Installers near Naperville average $79,340 a year, against a U.S. mean of $64,780. That is a factor of 1.225, so the labor half is scaled by it and the material half is not.

Source: BLS OEWS May 2025 for the Chicago-Naperville-Elgin, IL-IN metro area, SOC 49-9021.

What the quote should include

Design temperatures

The lines that turn a quote into an invoice

Ask about each of them before you sign. On a job this size they are the difference between $4,142 and something a quarter higher.

Use it as a bid check, not a quote

This prices an average job in average condition. Access, the state of what is being replaced, the season, and a crew booked out three months all move the real number, and none of them are in a national average.

If a bid lands outside $3,270 – $5,668, that is not automatically wrong — but it is the question worth asking out loud.

Nearby sizes

Read more