Standard efficiency
Around 80% AFUE, venting through the existing chimney. Sometimes the practical choice where side-wall venting isn’t possible.
New & replacement furnaces
Furnace Installation in Chicago, IL
Green Leaf Heating & Cooling connects Chicago homeowners with local technicians for furnace installation and replacement, from a straight swap of a worn-out furnace to a high-efficiency or modulating model with new venting. Call (312) 924-7223 and get a free estimate before any work starts.
Sized for the house, not the old box.
About furnace replacement
A New Furnace in Chicago, Sized for Your Home
The most common furnace installation mistake is copying the old unit’s size. Many Chicago homes have had new windows, insulation or additions since their furnace went in, and an oversized furnace short cycles, heats unevenly and wears out sooner.
A proper replacement starts with a heat-loss calculation for the house, a look at the ductwork and a check of the venting. Then you get options: standard or high-efficiency, single-stage, two-stage or modulating, each with a free estimate.
High-efficiency furnaces (90% AFUE and up) vent through plastic pipe out a side wall instead of the chimney and drain condensate, so the technician plans where the vent and drain will go. Older chimneys shared with a water heater may also need a liner once the furnace no longer uses them.
- ✓ High-efficiency gas furnaces
- ✓ Two-stage and modulating models
- ✓ Venting and chimney checks
- ✓ Free estimate before work starts
Your options
Furnace Replacement Options in Chicago
What a technician will walk you through when it’s time for a new furnace.
High efficiency
90 to 98% AFUE. More of the gas becomes heat, which matters over long Chicago winters. Vents through PVC pipe.
Two-stage
Runs on a low setting most of the time and high only on the coldest days: quieter, steadier heat and fewer cold spots.
Modulating
Adjusts its output in small steps to match the heat the house is losing. The most even temperatures and the quietest operation.
Matched with your AC
The furnace blower also moves your summer air. Matching the furnace and AC coil keeps both efficient.
Dual fuel
A heat pump handles mild weather and the furnace takes over in deep cold. See heat pumps.
How it works
How a Furnace Installation Works
The technician measures the house, looks at insulation and windows, checks the ductwork, gas line and venting, and asks where the house is uncomfortable.
You get a few options sized to the house, with what each includes and a free estimate. Nothing is ordered until you choose.
The old furnace comes out, the new one goes in with its venting, condensate drain, gas and electrical connections. Most installs take a day.
The furnace is started, gas pressure and combustion are checked, and you’re shown the filter, thermostat and any maintenance it needs.
STEP 01Home assessment
The technician measures the house, looks at insulation and windows, checks the ductwork, gas line and venting, and asks where the house is uncomfortable.
Planning a replacement
When to Replace a Furnace, and What Affects the Cost
Signs it’s time for a new furnace
- The furnace is around 15 to 20 years old or older.
- The heat exchanger is cracked, or a technician has flagged carbon monoxide concerns.
- Repairs are coming every winter and adding up.
- Some rooms never get warm, or the furnace runs constantly on cold days.
- Gas bills keep climbing although your habits haven’t changed.
Read more in signs your furnace needs replacing before winter.
What affects the cost of furnace replacement in Chicago
Every home is different, which is why you get a free estimate after a visit rather than a number over the phone. The main factors are:
- Size and efficiency. Larger and higher-efficiency furnaces cost more up front and less to run.
- Single-stage, two-stage or modulating. More stages mean more even heat and a higher equipment cost.
- Venting. Switching to a high-efficiency furnace means new PVC venting, and sometimes a chimney liner for the water heater.
- Ductwork. Undersized or leaky ducts may need changes for the new furnace to perform well.
- Access. Tight basements, crawlspaces and attic installs take more labor.
Utilities such as Peoples Gas and ComEd have offered rebates on qualifying high-efficiency equipment. Programs change, so check their current offers before you buy.
Furnace or something else?
If your home has radiators, you have a boiler rather than a furnace; see boiler repair and replacement. If you want cooling too, a heat pump or a dual-fuel system can do both.
Furnace installation FAQ
New Furnace Questions From Chicago Homeowners
Short answers to what Chicago homeowners ask most before they call.
(312) 924-7223Most straight replacements take one day. Installs that need new venting, ductwork changes or a different location can take longer.
It depends on the home’s heat loss, not just its square footage: insulation, windows, air leaks and ceiling height all matter. A technician calculates it rather than copying the old unit.
In a climate with long, cold winters, a high-efficiency furnace usually pays back more than it would somewhere mild, because it runs so many hours a year. Whether it fits also depends on where it can vent.
Yes, and it often makes sense: they share the blower and coil, and a matched pair runs more efficiently. See AC installation.
Furnace replacement in Chicago generally requires a permit from the city. The installer normally handles it; ask about it when you get your estimate.
Related services
More Heating Services in Chicago
01Furnace RepairNot sure it needs replacing? A diagnosis first.↗02Heat PumpsCold-climate heat pumps and dual-fuel systems.↗03AC InstallationReplace the AC with the furnace and match the pair.↗04Air Duct CleaningDuct sealing and changes so a new furnace performs.↗05Indoor Air QualityHumidifiers, media filters and smart thermostats with your new furnace.↗06HVAC MaintenanceYearly tune-ups to protect the new system.↗
Furnace installation across Chicago
Furnace installation in Your Neighborhood
Ready when you are
Ready for a New Furnace in Chicago?
Call (312) 924-7223 for a home assessment and a free estimate on furnace replacement options.
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