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What Happens if You Don’t Change Your Furnace Filter?


As you prepare for the weather to get colder in Denton, it’s time to think about how to stay as comfortable as possible all winter long. In order to do that, you’re going to need your furnace to be working as well as it can. How do you keep your furnace happy? A clean air filter will really help with that. What happens if you don’t change your furnace filter? Here’s what to expect.

Dust Will Accumulate

The furnace’s air filter is designed to trap dust and grit. It does help to keep that out of the air that circulates in your home, but the main purpose is to protect the furnace’s inner workings from the grime. The longer you go without changing it, the more dust will be caught in the filter. In a matter of months, it will be so caked with particles that it might as well be wearing a sweater.

Airflow Will Be Diminished

When your furnace’s air filter is wearing a sweater, less air will be able to get through. Not only will this decrease the amount of warm air that is able to flow through your vents and heat your home, it will also prevent air from moving through the furnace the way it is designed to do.

Without enough cool air flowing through to be heated, the little air that does get in will get overheated. The best you can hope for is that the limit switch will respond to the high temperatures by shutting the furnace down, further decreasing your flow of warm air and making it impossible to keep your whole home warm.

A worse possibility is that the blower fan motor will get hot enough to burn out. The electrical wiring can actually fuse together from high heat. Now, in addition to needing a clean air filter, you need a new blower fan motor.

Air Will Leak Around the Filter

As the furnace tries harder and harder to pull in enough air, it may manage to suck air around the filter. This air will not have been filtered. Worse, since it’s coming from right beside the dust-caked filter, it will contain even more dust than normal unfiltered air. 

Now, what air the furnace is getting will be heavily contaminated with particles. These bits of grit will get into the moving parts within the furnace, like fans and the bearings of the blower motor. They’ll increase friction and cause wear and tear.

Efficiency Will Be Reduced

Struggling to suck in enough air, shutting down and turning on again too frequently because of overheating, and keeping parts moving despite increased friction will all force the furnace to use more energy. As it consumes more fuel, your energy bills will go up.

Furnace Life Will Be Shortened

All these issues add up to a significant increase in the strain on the system. Parts are more likely to fail, and the furnace itself simply will not be able to keep working for as long as it should.

Avoid All These Problems by Changing Your Filter

Change your furnace filter every month during times when your furnace is in near-constant use or if you have heavily shedding pets or other sources of increased dust. Change the filter every 2-3 months when it’s in occasional use. If you have any questions about how to do that, our team is ready with answers for you.

Contact PRK Services, Inc. today for all your heating and cooling needs.

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