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Changing the Furnace Filter: The Basics on How to Do It

man-hold-furnace-filterOne piece of advice we stress when it comes to heating efficiency and effectiveness is regularly change the furnace air filter. (In most HVAC systems, the AC uses the same filter, so this advice applies throughout the year.) A clean furnace filter is necessary to ensure a furnace doesn’t waste energy, has proper airflow, and won’t collect dust and dirt inside the cabinet that may damage it.

You may not know how to change the filter, but it’s not difficult. Here’s a brief guide to the best practices when it comes to keeping a clean filter.

The furnace filter isn’t there to improve your air quality

Before we get into the basics of changing the filter, we want to address a common misunderstanding. The filter isn’t in place to help provide cleaner air to your house. It does remove some particles from circulating, but the point of the filter is to protect the furnace, not your breathing. The filter stops dust, lint, and other fibers coming through the return air ducts from getting inside the furnace cabinet. The trapped debris eventually will clog up the filter and require replacement.

The simple steps to changing the filter

First, locate the filter. There are two places it might be. The most common is on the furnace cabinet itself. Find where the return air duct connects to the cabinet; usually this is at the bottom of the cabinet where the air handler is located. The filter will be in a slot at this point. If it isn’t there, you can find it behind the vent over the return air duct in the house. Unscrew the vent cover and you’ll see the filter in place behind.

Now, remove the filter from its slot and discard it. Put in a fresh filter in its place—you can purchase them in packs from most home supply stores. The most inexpensive filters usually cost around a dollar each when purchased in packs. Stronger filters cost more, but won’t need to be replaced as often.

Make sure the filter is facing the right direction! Arrows on the side of the filter will show you which side of should face the incoming airflow. Line up the arrows with the sides of the slot so you know the filter is correctly in place.

We recommend writing the date you put in the filter with marker on the side of the housing of the filter. This way you’ll know how long has passed since the filter was replaced.

How often to replace the filter

How often the filter needs to be changed depends on the filter strength. Basic panel filters will last for about a month. Pleated polyester filters may last 3 to 4 months, and special media filters may last for 6 months of more. Check the filter regularly to get an idea of how often your filter needs changing.

(Note: We don’t recommend using permanent filters, which may allow for the development of mold and mildew.)

If you need assistance with your furnace in Wake Forest, NC or elsewhere in the Triangle Area, you can count on Comfort Master.

Comfort Master Heating & Air Conditioning, Inc. lets you enjoy the comfort you deserve. Schedule heating service with us today.

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