2 Ways You May Accidentally Kill Your Furnace this Winter

Most furnace breakdowns aren’t premeditated. They’re accidental and preventable. And here’s how they happen. 


Furnaces, like people, can suffocate when you restrict air from going in or out of them.

You can accidentally suffocate your furnace by:

  • Closing air vents
  • Not changing the filter

And when you do either of these things, it can lead to these problems:

Blower motor burnout

The furnace blower sucks air into the furnace and blows it out of your home’s vents. But a dirty filter restricts the air coming into the blower and closed vents can make it more difficult for the blower to send the heated air into back into your home.

Both of these problems create more work for your blower motor, causing it to burn out.

Heat exchanger crack

Your furnace heats air by blowing it over the heat exchanger. 

But if you have a dirty filter, you lower airflow over the heat exchanger, causing it to overheat and possibly crack. 

Besides being an expensive fix, a cracked heat exchanger can allow deadly carbon monoxide (CO) to leak into your home. 


The most common causes of neglect that lead to furnace breakdowns are:

  • Running the furnace without a filter
  • Skipping routine furnace maintenance

Running your furnace without a filter is silly. Filters are cheap. And they keep your furnace from getting full of dirt, causing problems like:

  • Blower motor issues
  • Malfunctioning sensors, which can shut your furnace down even if there’s nothing wrong

Skipping your furnace’s regular maintenance visit is also unwise. And that’s not just us talking. Maintenance is recommended by your furnace manufacturer, the U.S. Department of Energy, ENERGY STAR and local utility companies.

Ignoring your maintenance visit can lead to:

  • Blower repairs — Blowers need to be regularly cleaned and oiled to continue to run efficiently (especially if you’ve run your furnace without a filter).
  • Ignition issues — Your igniter or pilot light can malfunction if there’s dirt buildup on it.
  • CO poisoning — A cracked heat exchanger can leak dangerous carbon monoxide into your home.
  • Home water damage — If you have a condensing furnace, the condensate drain can back up and cause water damage in your home.

And if your furnace is newer, not getting regular maintenance can actually void your furnace warranty.

Prevent accidental furnace death

To keep from accidentally killing your furnace, just follow these 4 steps:

  1. Keep all air vents open and clear of obstructions
  2. Check your air filter monthly and change it when it’s visibly dirty
  3. Always replace your air filter when you take it out
  4. Schedule your furnace maintenance with a heating professional

Coolray is your Atlanta-area home comfort expert with specialists in heating, air conditioning, air quality, plumbing and electrical service. Have more questions? We’d be happy to help – just contact us online.

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