Evanston Furnace & AC Replacement: Forced-Air Homes

Evanston is best known as a boiler town, and for good reason: much of its pre-war brick housing still heats with steam or hot-water radiators. But that is only half the city. Drive through West Evanston, the south side, and the streets around Central Street and you find plenty of homes on forced air: postwar houses built with ductwork from the start, converted two-flats, and older homes where central heat and cooling were shoehorned in over the decades. If your Evanston home has a furnace and central AC rather than a boiler, this guide is for you. (If you are on radiators, start with our Evanston boiler replacement guide instead.)

Two kinds of forced-air Evanston home

The forced-air homes here tend to fall into two camps. The first is postwar construction on the west and south sides, built with ducts and now on its second or third furnace. The second is older brick homes and two-flats where a gravity furnace was converted or forced air was added later, threaded through a structure never designed around it. In both, the original equipment is frequently a builder-grade 80% AFUE furnace that has outlived its efficient years, paired with returns that are marginal and duct runs that are long and restrictive.

That history matters because it means a like-for-like swap usually repeats old mistakes. A proper furnace replacement in Evanston starts with a load calculation, not the old nameplate. Additions, insulation upgrades, and closed-off rooms change how much furnace a house actually needs, and the right size today is often smaller than what is coming out. Our furnace replacement cost guide breaks down what drives the price.

High efficiency, but respect the house

Stepping up to a high-efficiency 90-98% AFUE condensing furnace cuts gas use through a Chicago winter, but the install has to fit the home. Condensing furnaces pull so much heat from the exhaust that water forms, so they need a condensate drain and PVC sidewall venting instead of the old metal flue. In a finished Evanston basement or a tight utility closet, routing that venting cleanly and to code takes planning. It is real work, and it is part of why high-efficiency units cost more up front. Whether the fuel savings justify the jump is a fair question in a smaller home, and worth talking through honestly rather than defaulting to the priciest option.

Cooling near the lake

Evanston sits right against Lake Michigan, and the humidity that rolls in a few blocks east is part of the cooling challenge. Many of these homes got central air as a retrofit years ago, and a lot of that equipment is now on borrowed time. The condensers we see are frequently 12 to 15 years old and, in the older ones, still running phased-out R-22 refrigerant that is expensive to top off and no longer worth chasing.

When you replace an aging system, the outdoor unit is only half the story. In a dense brick home or a two-flat, the indoor coil, line set, and electrical often date back to the original retrofit and do not automatically match a modern condenser. A proper AC replacement in Evanston checks all three and matches the equipment as a system, so the new AC actually delivers its rated efficiency and dehumidifies the way a struggling old unit cannot. Our AC replacement cost guide covers the R-22 factor and what a fair, itemized quote should include.

What it costs, and doing both at once

Treat these as planning ranges, not quotes. Furnace replacement on the North Shore typically runs roughly $4,500 to $9,000 installed, and central AC replacement roughly $4,000 to $8,000, with final pricing driven by home size, efficiency tier, and the condition of your ductwork and venting. Because so many Evanston furnaces and condensers are the same vintage, they often reach the end together. When both are near end of life, replacing them as one matched system means a correctly sized coil, a pairing engineered to run as a unit, and one installation instead of two, which is usually the cheaper path over time.

Rebates in 2026

For 2026, utility rebates are the incentive to look at. Nicor Gas has offered rebates on qualifying high-efficiency furnaces and smart thermostats, and ComEd offers rebates on qualifying cooling equipment. Amounts change, so confirm the current numbers with your utility before counting on them. The federal 25C tax credit is no longer in the picture: it expired for equipment placed in service after December 31, 2025, so a 2026 install does not qualify.

Planning it out

Whether you are replacing a tired furnace, a failing R-22 AC, or both, the fundamentals in an Evanston forced-air home are the same: size to the actual house, match the equipment as a system, vent a condensing furnace properly, and work cleanly in finished or shared space. Licensed, insured installers should haul the old equipment away and register the warranty before they leave.

Learn more about local work on our Evanston page, and when you want a real number for your home, get a written free estimate or call (847) 752-4418.