Illinois winters don’t ease you in. Temperatures drop fast, stay low for weeks at a time, and the heating system runs harder than it does at any other point in the year. Most problems don’t start in January, but that’s when they announce themselves. Working with experienced heating repair contractors before something fails completely is almost always less expensive and less disruptive. Here’s what tends to go wrong and what’s usually behind it.
No Heat at All
First things first: check the circuit breaker. Then the thermostat. Make sure it’s set to heat, not cool, and that the set temperature is actually above what the room currently is. Sounds obvious. You’d be surprised.
If those check out, you’re probably looking at a faulty ignitor, a failed control board, or a gas supply issue. Pilot light problems on older furnaces, electronic ignition failures on newer ones. Both are fixable but need a technician.
Furnace Runs, House Stays Cold
Different problem. If you can feel warm air at the vents but the house won’t reach temperature, you’re likely dealing with one of three things: a clogged filter restricting airflow, duct leaks releasing conditioned air before it gets to the living space, or a system that’s genuinely undersized for the cold snap.
Start with the filter. Change it if it’s been a while. If that’s not the issue, someone needs to look at the ductwork or assess the system output.
Something Smells Off When It Kicks On
A dusty smell at the beginning of heating season is nothing to worry about. The system is burning off dust that settled during summer. Clears up after a few cycles.
Burning plastic or rubber is different. That needs immediate attention. Could be an electrical issue or something that found its way into the system. A rotten egg smell means stop everything, turn the system off, get out of the house, and call the gas company. That’s the odorant added to natural gas. Carbon monoxide is a separate and equally serious risk with any gas heating system — the CDC’s overview of CO exposure and symptoms is worth reading if you’ve never gone through it. That’s the odorant added to natural gas.
Some Rooms Are Hot, Others Won’t Warm Up
Uneven heating is frustrating because it doesn’t feel like a failure, just an inconvenience. Usually comes from closed or blocked vents, damper problems in the ductwork, or a blower motor that isn’t moving air the way it should.
Rooms at the far end of the duct run or on exterior walls with poor insulation are almost always the cold spots. A technician can check static pressure and airflow at individual registers to find where the problem is.
Short Cycling
The furnace turns on, runs for a minute, shuts off, starts again too soon. Never completes a full cycle. House never fully warms up. Hard on the compressor.
Usually traced to an overheating heat exchanger, a dirty flame sensor, or a thermostat in a bad spot. Worth addressing quickly. Short cycling accelerates wear on the parts that cost the most to replace.
Strange Sounds
Banging at startup often points to delayed ignition. Squealing is usually a worn belt or motor bearing. Rattling could be a loose access panel or debris somewhere in the system. None of these go away on their own, and most of them get worse.
Bottom Line
Deal with it before it becomes a failure. If the system is already acting up, don’t wait it out hoping it stabilizes.A professional HVAC company in Glenview can usually diagnose what’s happening on a single visit and walk you through what needs to be repaired now, what can wait, and what it’ll cost. Top Air Solutions has been handling heating repairs in this area since 2009, from straightforward fixes to full system replacements.