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Cool Touch Air Conditioning and Heating Blog

What’s That Weird Smell From My Furnace?

furnace-repairWhen we fire up our furnaces in the winter after returning from the cold, we think of the nice and cozy feeling of getting to relax without the need for a blanket or sweatshirts. The last thing you usually think about is the smell. That’s why it would be incredibly strange if your furnace started emitting odors all the sudden!

Some odors are completely harmless and will go away, and others might be very dangerous. To help you tell the difference between the two, we’ve compiled a list of some of the most common odors that your furnace might emit.

Dust and Dirt

This is something you would have noticed back when you first started using your furnace in the new season. During the spring and summer, when you weren’t using your furnace, it had plenty of time to accumulate dust and dirt. Firing up the furnace will burn some of that off and create a distinct odor.

Before calling in for furnace repair in Phoenix, you’ll want to give it some time by letting it run for a few days. You should also make sure that the air filter has been changed out. If the odors persist, it won’t hurt to call in for a professional opinion.

Rotten Eggs or Sulfur

Now this is a smell that you should never ignore. This is the distinct smell of a gas leak. Natural gas is normally odorless, but this odor is chemically added to the gas for the purpose of notifying you that a leak is present.

The fact is, gas leaks do happen outside without much consequence—that’s simply because there’s so much atmosphere for the gas to disperse into. For your furnace, it’s the opposite. A gas leak in a contained space is a recipe for disaster.

If you do detect a gas leak, never attempt to find the leak, and don’t operate any appliances—even the light switch! Leave the home immediately and call your utility company for help.

Overheating Odors

If your furnace is getting too hot, it can produce a range of different smells. Hot metal, burning oil, hot plastic, even rubber. If that’s the case, immediately turn the furnace off and call for repairs.

There are various reasons that your furnace could be overheating. One reason may be that the limit switch needs replacement. This component is designed to shut off the furnace in the event of overheating. However, if the furnace has been overheating several times without your knowledge, the limit switch may wear out.

A furnace that overheats without that failsafe may end up burning components, wire insulation, and other components that emit bad odors.

Vent Obstruction

If there’s an obstruction in the air ducts, that could end up producing an odor. What that odor is will depend on the obstruction, whether it be a piece of loose insulation or a deceased pest. This can also cause some airflow issues that might reduce your furnace’s efficiency.

If your furnace is acting (or smelling) funny, don’t hesitate to call up a pro. Contact Cool Touch Air Conditioning and Heating today.

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