HVAC Repair in Naperville, IL
Homes here need heat from October through May and cooling from June through August. If your system quits, tell us what it's doing and a licensed contractor who covers DuPage County will get in touch.
Tell us about the job
It takes about a minute.
Eleven months of work, most of it in the cold
Your furnace carries this house from October through May. On winter nights that average 19°F, it runs long and often, and every start puts a load on the igniter and the flame sensor. Those are the parts that tend to fail first, usually on the coldest nights, because that's when the furnace is working hardest.
Summer is shorter here, June through August, with afternoons around 82°F. That's enough heat for a struggling air conditioner to fall behind and run without ever quite catching up. DuPage County also sees real storms, 15 winter storms and 180 damaging wind events over the past ten years, and outages come with them. Statewide, 16% of households lost power for 24 hours or more in 2024. Most furnaces and air conditioners come back on their own once power returns, but a system that was already struggling before the outage will still be struggling after it.
- 8 months
- October through May, your system heats
- 3 months
- June through August, it cools
- 19°F
- the average winter night it heats against
- 82°F
- the average summer afternoon it cools against
NOAA nClimDiv, 1991–2020 normals
A new furnace and air conditioner would cut about $160 a year off heating and cooling for a typical DuPage County home.
Estimates for a typical DuPage County home, compared with an older unit built to the previous federal minimum, from EIA household energy data, Illinois fuel prices and NOAA climate normals. Your home will differ.
Repair makes sense when one part has failed.
Replacement makes sense when the furnace's heat exchanger is cracked, the air conditioner's compressor has failed, or repairs keep coming.
In Illinois, HVAC licensing for homes is left to the cities and towns.
In DuPage County, what applies depends on which municipality the house sits in. Some towns license HVAC contractors, others leave it open, and the county line does not tell you which. There is no statewide test or state record to check against, so whatever protection exists comes from the local building office, not from Springfield.
For this repair, the part worth the most care is the gas connection, since a bad joint is a safety hazard and not just a comfort issue. Whether a contractor is licensed for that work depends on the town, and that answer changes from one DuPage County municipality to the next.
Source: Illinois General Assembly
- Why is my heat not working?
- Start with the thermostat. Make sure it is set to heat and the temperature is set above the room temperature, since a setting bumped a degree or two can leave a furnace idle on a night that drops to 19 degrees. If the thermostat looks right, check the breaker and the furnace switch, which looks like a light switch near the unit. Most furnaces here run on gas, so if the burners will not light after that, the igniter or the gas valve is a likely cause, and that is a job for a contractor.
- Why is my system running but not cooling the house?
- If air is moving but it is not cold, check the filter first. A clogged filter chokes airflow across the coil, and on an 82 degree afternoon that alone can keep a house from cooling down. Next check that the outdoor unit is running and not covered in leaves or debris. If the filter is clean and the outdoor unit is clear and the air still is not cold, the system likely needs a contractor to look at the refrigerant charge or the coil.
- What can I check before calling for HVAC repair?
- Check the thermostat settings, the batteries in it if it has any, and the breaker for the system. Check the filter and replace it if it is dirty, since a blocked filter causes both weak heating and weak cooling. Look at the outdoor unit and clear away anything piled against it. If the system still is not working after that, a contractor will need to diagnose it, and after a storm it is worth mentioning to them if the power went out, since winter storms and wind events are common enough here to knock out power and reset equipment.