Tell us about the job
Takes about a minute. No obligation.
A furnace in this county has been running against real weather, season after season, and the parts that fail first are the ones that handle combustion airflow and pressure. 275 severe weather events were recorded in DuPage County, Illinois between 2015 and 2024. At that rate, contractors who work furnace repairs here find cracked heat exchangers and worn draft inducers at a frequency that shapes where they look first. Age matters, and so does installation quality, but in a county with a record like this, a contractor who skips the pressure switch and the venting system before calling a failure age-related is missing what the equipment has actually been through.
Furnaces in houses built for older equipment run on parts that may have cycled through two or three manufacturer generations since the house went up. Half the homes in DuPage County, Illinois were built in 1978 or earlier (2020-2024 ACS 5-year). When a contractor opens a furnace in stock like this, the first question is whether the components it takes are still in production, and that answer shapes the repair scope more than the mechanical failure itself does. A heat exchanger or control board in a unit retrofitted into an older building can be specific to a model run that ended years ago, which turns a straightforward fix into a sourcing problem.
The Parts of a Furnace a Contractor Checks First
The furnace itself sits in the basement, utility room, or closet and is the piece a contractor goes to first. Inside it, the heat exchanger is the part most likely to be behind a heating failure or a safety concern, and the burners that fire beneath it are checked alongside it. The blower motor and its fan wheel push conditioned air into the supply side of your home, and a sluggish or seized blower shows up as weak airflow at every register.
The flue pipe runs from the furnace up and out of the house, carrying combustion gases away, and a blocked or cracked flue can shut a furnace down or trigger its safety switches. Sitting on or near the unit, the igniter and flame sensor work together to start and confirm a burner cycle, and both are common reasons a furnace runs briefly then cuts off. The thermostat on the wall is where a contractor often starts, since a wiring fault or a failed sensor there can look exactly like a mechanical problem deeper in the system.
The drawing shows a representative layout, and a licensed contractor determines which components and conditions apply to your specific equipment and home.
Get matched in DuPage CountyDuPage County, by the numbers
275 severe weather events were recorded in DuPage County, Illinois between 2015 and 2024.
NOAA National Centers for Environmental Information, Storm Events Database, bulk CSV export, events 2015-01-01 through 2024-12-31.Half the homes in DuPage County, Illinois were built in 1978 or earlier (2020-2024 ACS 5-year).
U.S. Census Bureau, 2020-2024 American Community Survey 5-Year EstimatesDuPage County, Illinois holds 367,152 housing units (2020-2024 ACS 5-year).
U.S. Census Bureau, 2020-2024 American Community Survey 5-Year EstimatesOwners occupy 73.1% of the occupied homes in DuPage County, Illinois (2020-2024 ACS 5-year).
U.S. Census Bureau, 2020-2024 American Community Survey 5-Year EstimatesCodes & Standards for Furnace Work in DuPage County, Illinois5 sourced rules and standards
What Happens When the Contractor Arrives
Non-weatherized gas furnaces manufactured on or after November 19, 2015 must reach 80.0 percent AFUE.
Non-weatherized oil-fired furnaces manufactured on or after November 19, 2015 must reach 83.0 percent AFUE.
Mobile home gas furnaces manufactured on or after November 19, 2015 must reach 80.0 percent AFUE.
Non-weatherized gas furnaces manufactured on or after December 18, 2028 must reach 95.0 percent AFUE, up from the 80.0 percent minimum that applies to units manufactured before that date.
Licensing and Legal Requirements in DuPage County, Illinois
Illinois leaves HVAC licensing to the municipality: state law lets the corporate authorities of each city or village examine, license and regulate heating, air conditioning and refrigeration contractors, and caps the licence fee they may charge at $50 — so who licenses you depends on the town you work in.
Severe Weather Events in DuPage County
Extreme weather puts furnaces under pressure at the worst possible moments, and DuPage County has its own pattern of what that pressure looks like. A furnace that runs hard through repeated weather events accumulates wear that local contractors see firsthand.
275 severe weather events, 2015–2024. Source: NOAA National Centers for Environmental Information, Storm Events Database.