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3 Things to Know About Your Furnace’s Filter

Every furnace has a filter that removes particles from the air as air moves through the furnace. If you own a home, you should know these three things about your furnace’s filter so that you can keep it operating properly.

1. Furnace Filters Get Clogged with Particles

You need to remove trapped particles from your furnace’s filter periodically. If the debris that a filter traps remains in the filter, the filter’s effectiveness will decrease and airflow through the furnace can become restricted. What the filter-cleaning process for your system involves depends on what type of filter the furnace has.

Disposable furnace filters are easy to replace. You’ll find suitable replacements both online and at local stores, and you can simply slide out the current filter and slide in a fresh one. Throw away the old one after you remove it, for these are one-time-use filters. Your furnace’s manual will show you where to access the filter and how to change it out.

Washable filters don’t get thrown away when they’re dirty, Instead, you can clean a washable filter with water. After cleaning, make sure you let the filter dry before you reinsert it into the furnace, for a wet filter in a warm furnace can lead to unwanted mold and mildew growth on the filter.

You should clean off a washable filter on a nice weather day. You’ll want to wash the filter outside so that all the debris it has collected doesn’t reenter your home’s ductwork, and a filter won’t take too long to dry off if it’s outside on a sunny day.

You won’t find a hard-and-fast rule for how often you should go through either of these processes, but there are some guidelines. In general, you should replace or clean your furnace’s filter as follows when you have the heat on regularly:

  • Every 6 weeks if someone in your house has asthma or allergies
  • Every 2 months if you have pets
  • Every 2 to 3 months if you have children

You can also check your filter monthly and replace or clean it if it looks dirty with a bunch of debris.

2. Furnace Filters Must Face a Certain Way

When you replace your furnace’s filter, make sure you reinsert a new or clean filter properly. Furnace filters face a specific direction so that air flows through them in a certain way, and a filter won’t be effective if it’s put in backward.

To find out what direction your furnace filter faces, you can either check the current filter’s orientation when you remove it or look up the proper orientation in the owner’s manual. An arrow on the filter might also indicate what direction air should flow in, so you can use this if you know how the air moves through your furnace.

3. Heat-Pump Filters are Used in All Seasons

If your home has a heat pump, you need to replace the furnace filter year-round.

Since heat pumps are dual systems that act both as furnaces and air conditioners, they don’t get the warm-weather break that furnaces normally do. You’ll use a heat pump both in the summer and the winter, and the filter will remove particles anytime you have the heat or air conditioning on.

The steps to replace a filter on a heat pump are mostly the same as those for a standard furnace. The only difference is that a heat pump’s filter can be either in the air handler, which is part of the furnace portion of the system, or directly behind air returns. The owner’s manual for your system will show where its filter is.

For help with your furnace’s filter or any part of your heating system, contact L&L Home Improvements.

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