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How Often Should You Change Your Furnace Filter?

signs you should change your filter

Winter is approaching here in the St. Louis area, which means we’ll be spending a lot more time indoors in the coming months. For that reason, the heating season is one of the most important times of year to keep up with changing your furnace’s air filter. So let’s take a look at how often you should change your furnace filter in order to best protect your heating unit and provide clean indoor air for your home.

What type of filter do you have installed?

When you are determining how often to change your furnace filter, you need to first know what type of filter you currently have installed. Some of the most common filters are:

  • Fiberglass filters. If you’re using a standard fiberglass filter, you should be changing it every month. Particles can build up quickly on these, especially during the heating season, and you can protect your furnace from damage by replacing it every month.
  • 1 inch pleated filters. One inch pleated filters typically last a bit longer than fiberglass filters. You should expect to change them every 60-90 days, but it would be a good idea to check the condition of them every month.
  • 4 inch pleated filters. Because 4 inch pleated filters have more area for particles to build up, they require less frequent changes. Many of these can last between 6 months and a year before needing to be replaced. As with one inch pleated filters, however, you should still be checking the condition of them every month or two in case particles have built up quicker than expected.
  • Permanent washable filters. If you have a permanent washable filter, it’s important that you thoroughly clean and dry it once a month.

Other variables to keep in mind

Beyond the type of filter that you have installed, there are a couple of other factors that can influence how often you should change your furnace filter. For starters, the more your furnace is running, the more often your filter will need to be changed. That usually means that the coldest months of the year will require the most frequent filter changes.

You should also keep in mind that some households produce more airborne particles than others. If you have numerous pets in your home or a smoker in your family, for example, your filter might require more frequent changes than what’s listed above.

If you have any questions about how often you should change your furnace filter, or if you’d like a heating system serviced or installed in your home, contact Jerry Kelly, your St. Louis area heating and cooling company.

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