Every year the first cold morning does the same thing in Southern Illinois: the furnace that sat quiet since April gets asked to run all day, and the phone at every heating company lights up. The people who call in November wait a week. The people who spent twenty minutes in October did not call at all.
Here is the part that matters if you ever plan to sell. A buyer’s inspector runs the furnace, checks the filter, looks at the flue, and looks at the attic and crawlspace. A system that was clearly looked after makes a report short. A system with a filter the color of a doormat makes the buyer wonder what else got skipped.
So this Sunday’s homework is the heating-season walk. Six stops, one afternoon, and most of it costs less than a pizza.
1. The Furnace Filter
🌡 Check It, Then Write the Date on the New One
Pull the filter and hold it to the light. If you cannot see through it, replace it. Write the date on the edge in marker so you know when it was last changed. A clogged filter makes the system work harder and is the single most common thing a tech finds.
Cheap now: a filter. Expensive later: a stressed blower motor and an inspector’s photo of a gray, matted filter.
2. Fire It Up Once, Now
🔥 Run the Heat Before You Need It
Turn the thermostat to heat and let it run a full cycle while the weather is still mild. You are listening for odd noises and smelling for anything burning. A little dusty smell the first time is normal; it should clear in a few minutes. If it does not, or the system will not start, you have time to get a service call on the calendar instead of begging for one on the coldest night.
If the furnace is old or you have never had it serviced, an annual tune-up by a licensed HVAC company is worth asking about. Gas appliances in particular are not a do-it-yourself job.
3. Chimney, Fireplace, and Flue
🏠 Look Up Before You Light Anything
If you have a wood-burning fireplace or stove, have the chimney inspected before the first fire, especially if you have not in a few years. Creosote buildup and cracked liners are real fire risks. Check that the damper opens and closes, and look for birds or animals that moved in over summer.
Gas fireplace owners: make sure the pilot lights and the glass and logs are in good shape, and check that your carbon monoxide detectors have fresh batteries.
4. The Dryer Vent
💧 The Forgotten Fire Risk
Pull the dryer away from the wall and look at the vent hose. It should be a smooth or rigid duct, not a crushed accordion, and it should vent outside. Clean out the lint from the hose and from the outside flap. Lint buildup is a well-known cause of house fires, and inspectors do flag a dryer that is not vented properly.
5. Attic and Crawlspace
🔧 Flashlight, Five Minutes
Pop your head into the attic. You are looking for daylight where there should not be any, wet or stained insulation, and insulation that has been pushed aside or is thin. In the crawlspace, look for standing water, torn vapor barrier, and pipes that run along an exterior wall without insulation.
Do not walk on the ceiling joists in the dark or crawl anywhere you are not comfortable. If something looks wrong, take a photo and call a pro. The photo alone will save you time.
6. Sump Pump and Basement
💦 Pour a Bucket In
If you have a sump pump, pour a bucket of water into the pit and watch it kick on, empty, and shut off. Check that the discharge line runs well away from the foundation. A pump that has never been tested is a pump you are hoping works.
Cheap now: a bucket of water. Expensive later: a wet basement on the one night it rains three inches, and the line in the buyer’s report that says “evidence of past water intrusion.”
The Honest Version of Why This Works
A clean filter does not raise your list price. What it does is take items off a buyer’s list of worries. A house where the heat comes on, the vents are clean, and the basement is dry reads as looked after, and buyers pay more attention to a house that does.
And to be clear, this is not a replacement for a licensed HVAC, chimney, or electrical professional, and it is not a way around disclosure. If you know about a real problem, a failing furnace, a leaking basement, deal with it and disclose it straight. This list is for the small stuff.
✅ Print This: The Heating-Season Walk
- Check the furnace filter; replace it and write the date on it
- Run the heat for a full cycle while the weather is mild
- Have the chimney inspected before the first fire
- Clean the dryer vent hose and outside flap
- Flashlight look at the attic and crawlspace
- Test the sump pump with a bucket of water
🏠 Thinking About Listing This Winter or Spring?
Send us your address and we’ll tell you what your house is worth today and what, if anything, is worth fixing before it hits the market — and what isn’t. We run sales, mortgage and title under one roof, so we see every inspection that comes through.
Heating-Season FAQ
How often should I change my furnace filter?
Do I need to service my furnace every year?
Does a chimney inspection really matter if I rarely use the fireplace?
Will these fixes help me sell my house for more?
📱 Got a Question About Your House? Text Greg.
Not sure whether something on this list is worth fixing? Text Greg Holthaus directly — just tell him you saw his blog. He’ll give you a straight answer, match you with the right broker, and tell you honestly if the answer is “don’t worry about it.”
Text Greg · 618.925.8654
Who is Greg Holthaus?
Greg Holthaus is the Owner and Designated Managing Broker of Southern Illinois Realty Experts, with 25+ years in Southern Illinois real estate and more than 10,000 transactions closed. He leads a full-service operation — home sales, mortgage, title, and property management under one roof — with offices in Marion, Herrin, and Carbondale. Meet Greg ›
About this post: General homeowner guidance based on 25+ years of listing and closing homes across Southern Illinois. It is not a home inspection, not electrical, plumbing or structural advice, and not a statement of what any inspector, lender or code official will require — those vary by property and jurisdiction. Hire licensed professionals for electrical, plumbing, structural and gas work. Nothing here replaces the Illinois Residential Real Property Disclosure Report or your obligation to disclose known defects, and nothing here is a guarantee of sale price, closing date, or outcome. Want a specific read on your house? Ask us for a Comparative Market Analysis.