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Blue Ash, Ohio 45241
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The National Difference: Longest running Bryant dealer in Cincinnati

Why Are My Furnace Filters So Dirty?

With winter here, many Cincinnati residents are finding themselves paying closer attention to their heating systems than they have in many months. It’s true that the cold weather is only going to continue to get colder, so how is your furnace filter doing? If you haven’t checked in a while, now is the time.

Dirty furnace filters are surprisingly common among Ohio homeowners, which often leaves people wondering how their filters ended up getting so filthy. There are a number of different causes, with the following being the most common sources of the issue.

1.) Your Furnace’s Fan is Set to “On”

It’s important to take a close look at the fan setting on your thermostat, which is something that many people don’t pay much attention to. If it’s set to “on” instead of “auto,” the fan in your furnace will run constantly, exposing the filter to contaminants 24 hours per day. Under these circumstances, you can expect it to get much dirtier than it would if the fan was set to “auto.” This way, the fan will only turn on during heating cycles.

2.) Your Home’s Air is Loaded with Contaminants

While it’s essential that a home be airtight in order to foster true energy efficiency, this often means putting extra effort into filtering and ventilating the air inside. If your air is loaded with contaminants to begin with, the filter on your furnace doesn’t stand a chance. This problem can be especially bad if you have pet in your home, as dander can get kicked up and settle into the filter.

3.) It’s Been Colder than Usual Outside

When the chilly winds blow, many people turn on their heating systems to keep temperatures stable. It should stand to reason, then, that the colder the weather outside is, the more likely it is that your furnace will be running, which means its filter will be more apt to clogging.

4.) The Filter is Of Poor Quality

It’s important to realize that not all filters are created equal, and some function at much higher levels of performance than others. In most cases with furnace filters, you get what you pay for. Cheap filters are often meant to last only 30 days, and a month can go by really fast. Staying away from cheap filters can help to give you a little extra breathing room.

Have more questions about your furnace and its filters? Contact us today to learn more or to schedule an appointment for heating system maintenance.


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It does not constitute professional advice. All information is subject to change at any time without notice. Contact us for complete details.