As the leaves fall and temperatures drop, your heating system is about to become your home’s MVP. But before you crank it up for the season, there are seven common mistakes homeowners make that can seriously shorten the life of your system, or worse, leave you freezing during a cold snap.

Here’s what not to do if you want your system to keep running strong (and your wallet happy).

1. Skipping the Pre-Winter Maintenance

“It worked fine last year, it should be fine this year, too!” – Famous last words.

Why it’s a problem: Dust buildup, loose connections, or small issues can quietly develop into major breakdowns. Annual maintenance can catch these early, saving you from costly repairs or a mid winter emergency.

Fix it: Schedule a professional HVAC inspection before the first cold snap hits. It’s cheaper than a repair or a new furnace.

2. Forgetting to Change (or Clean) the Air Filter

Out of sight, out of mind…until your system is choking on dust.

Why it’s a problem: A dirty filter restricts airflow, making your system work harder than it should. That extra strain can lead to overheating and premature system failure.

Fix it: Replace disposable filters every one to three months during heavy-use seasons. If you use reusable filters, clean them according to the manufacturer’s instructions.

3. Closing Too Many Vents or Doors

Trying to “force” heat into highly used rooms? That trick backfires.

Why it’s a problem: Closed vents and doors disrupt airflow and can actually create pressure imbalances. Your system ends up working inefficiently, and over time, this can damage components like the blower motor.

To fix: Keep most vents and interior doors open to maintain consistent air circulation throughout the house.

4. Ignoring Strange Noises

Banging, screeching, rattling – it’s not just “old house” charm.

Why it’s a problem: These sounds often signal worn out belts, motor issues, or airflow problems. Waiting until the system breaks down will only make the repair more expensive.

To fix: Call a professional at the first sign of weird noises, catching probelms early can extend your system’s life.

5. Cranking the Thermostat to “Speed Up” Heating

Your furnace isn’t a microwave.

Why it’s a problem: Setting your thermostat to 85 won’t heat your house any faster, it just keeps the furnace running longer, wasting energy and increasing wear.

To fix: Be patient and use programmable settings to gradually bring your home to a comfortable temperature.

6. Not Testing the System Before It’s Freezing Outside

There’s nothing worse than your heat dying on the first 30 degree night.

Why it’s a problem: If you wait until it’s already cold to turn your heat on, you won’t have time to fix issues before your home becomes uncomfortble or unlivable.

To fix: Run your heating system for 15 to 20 minutes during early fall to test its functions. If something’s wrong, you’ve still got time to schedule repairs.

7. Skipping Carbon Monoxide Safety Checks

If your heating system uses gas, this one’s critical.

Why it’s a problem: Faulty heat exchangers or gas leaks can release carbon monoxide, a dangerous and odorless gas that puts your family at serious risk.

The fix: Have your system inspected for CO leaks during your seasonal maintenance. Also, check that your carbon monoxide detectors are working and up to date.

Don’t Gamble with Winter Comfort

Taking an “it’ll be fine” approach to your heating system is a risky (and expensive) bet. These seven simple steps can prevent breakdowns, reduce your energy bills, and give your heating system a longer, healthier life.