September 29, 2026
Much of Moline’s housing went up before 1960, and plenty of it before 1940. Those homes have outlived several furnaces. Each replacement went into the same basement and usually connected to the same chimney and ductwork that served the one before it.
That history is why we treat furnace maintenance in Moline a little differently than in a newer subdivision. A yearly visit keeps the furnace itself in shape, and in an older home it also checks how the new equipment gets along with the old house around it. Below, we walk through what a heating season does to a furnace, why older homes add risks of their own, and when to call us before your annual visit is due.
A furnace in the Quad Cities can run thousands of hours between October and April. Every cycle wears on it in ways you can’t see from the basement stairs.
None of this happens all at once. It builds quietly over a season, which is why a once-a-year check catches most of it before it turns into a breakdown or a safety problem.
“Annual” also depends on what heats your home. A gas furnace paired with central air needs one heating check in the fall and one cooling check in the spring, since the blower and ductwork serve both. A heat pump runs in both seasons, so it gets the same twice-a-year attention. A boiler, which some older Moline homes still use for radiators, has its own list: pressure, the expansion tank, circulator pumps and the relief valve. Whatever you have, the fall visit is the one to protect, because it comes right before the months your system can’t afford to fail.
Many Moline furnaces vent through a masonry chimney that was built for a coal or oil furnace decades ago. Mid-efficiency gas furnaces can vent that way safely when the chimney is sound and properly lined. Over time, though, the acidic moisture in flue gases eats at mortar and clay tile, and a chimney that drafted well for years can start to fail.
The biggest risk shows up after a furnace upgrade. A new high-efficiency furnace vents through PVC pipe out a side wall, which leaves the gas water heater alone in the old chimney. That chimney is far too large for one small appliance. The flue gases cool before they reach the top, moisture condenses inside, and the water heater can start spilling exhaust back into the basement. The industry calls this an orphaned water heater, and it’s one of the most common problems we find in older Quad Cities homes. If you’re planning a furnace replacement in Moline, ask the installer how the water heater will vent once the new furnace is in.
Last November we did an annual visit on a 1940s brick two-story near 23rd Avenue. The owners had switched to a high-efficiency furnace three years earlier, and that installer left the water heater venting into the original unlined chimney without checking whether the chimney could still draft for one small appliance. Nobody had run a draft test since. Ours showed the water heater spilling exhaust for several minutes after each start, and we found white staining and loose tile at the base of the flue. We shut the water heater down, installed a properly sized chimney liner, and confirmed it drafted correctly before turning it back on.
The obvious reason for a yearly visit is avoiding a cold night with no heat. There are three others worth knowing.
Safety. Combustion problems, cracked heat exchangers and venting failures are all sources of carbon monoxide. Illinois law requires a working carbon monoxide alarm within 15 feet of every room used for sleeping. Alarms are the last line of defense. Annual maintenance is how you keep them from going off.
Your warranty. Many furnace manufacturers require proof of regular professional maintenance to honor a parts warranty. Check the terms for your unit and keep every service record.
Airflow and efficiency. A clean blower and filter move the air your system was designed for. Restricted airflow raises operating temperatures, shortens the life of parts and makes the furnace run longer to heat the same house.
Our furnace maintenance visit covers the furnace and everything it connects to. We clean and test the flame sensor and ignitor, inspect the burners and heat exchanger, run a combustion analysis and check gas pressure. We check the inducer, blower motor and wheel, wiring and safety switches, and replace the filter if you’d like.
In older homes, we add the house to the list. We run a draft test on every gas appliance connected to the chimney, inspect the flue connector and the base of the chimney for deterioration, and check for carbon monoxide at the appliances and in the living space. We also look at the basement ductwork for loose joints and gaps. If we see old cloth or paper duct wrap that may contain asbestos, we’ll tell you and leave it undisturbed.
If your furnace has a whole-house humidifier, we service that too. Quad Cities winter air gets dry enough indoors to crack wood trim, irritate sinuses and build static shocks, so a working humidifier earns its place. A neglected one does the opposite: the water panel scales over with minerals, the drain clogs, and standing water can drip onto the furnace or grow mold in the ductwork. We replace the panel, clear the drain and check the setting against the outdoor temperature so the windows don’t sweat.
You’ll get a written summary of what we found, what we fixed and anything to plan for.
Don’t wait for your scheduled appointment if you notice any of these:
If the furnace has already stopped working, see our page on furnace repair in Moline.
Our technicians work on both sides of the river every day, and older Moline homes are a big part of that work. Book furnace maintenance in Moline early in the heating season, and we’ll check your furnace, your chimney and everything in between, then sort what needs attention now from what can wait. Call (563) 582-8884 to get on the calendar.
