Why Change Your Furnace Filter?

by: Katey Gallagher

I will be the first to admit, that before I met my now husband (Chris Gallagher), I knew nothing about furnaces and air conditioners! I had my own home in Cincinnati and I couldn’t even tell you where my furnace was located! Now that I’ve been in the industry for years, I have a much better grasp of the ins-and-outs of heating and cooling a home. As service manager of our company, I work with our customers on a daily basis who have questions, similar to the ones I had before starting in this business. After hearing all these familiar questions, I felt like it would be helpful to share our knowledge with our customers. Hence why we started this video blog!

One of the comments I get a frequently is, “I didn’t realize I needed to change my filter that often”, and I believe it! I don’t think frequency of filter changing on your furnace or air handler is common knowledge. And I definitely don’t think people understand how much a dirty filter can negatively impact your heating AND cooling system’s operation all year around.

Why is it so important to clean my air filter on my furnace?

The obvious reason to change your furnace filter is because that filter is what is removing all the dust, dander and debris from your air in your home. Remember, there are TWO filters in your house – your furnace filter and your lungs! Let’s make sure the furnace filter is taking the brunt of the dust and allergens, not your body.

The less obvious reason to change your filter, is that dirty filter will negatively impact your furnace operation and in the long run, cause it to break, which may cost a lot of money in repairs.

What happens to your furnace or airhandler when you have a dirty filter?

Since your furnace is what moves the air during heating AND cooling season throughout your home, a dirty air filter can stop that air from moving. What happens is the fan inside your furnace/airhandler can’t pull air it needs from your duct work causing it has to work harder than it should. A good example of this is clothes dryer! If you don’t clean the filter on your dryer it can’t get enough air to dry your cloths and may break. Can you imagine not changing that filter? Well, your furnace filter is equally as important because a dirty furnace filter can cause:

  • It will cost you more money to operate your system because it has to work harder to satisfy your thermostat settings
  • Your home will become dirtier because the filter is full and can’t catch the dirt, so it sends it back into your home.

Costly repairs will occur, such as:

  • Blower motor repair of replacement
  • In cooling season: not getting enough air across your evaporator coil cancause it to ice up and your AC to stop working. The water from the ice may harm expensive electrical components inside your unit
  • In heating mode not getting enough air across your heat exchanger (the fire compartment inside your furnace) causes excess heat and may cause your heat exchanger to crack – releasing harmful carbon monoxide into the air!

With this information in hand, here is our recommendation on the frequency for changing your filter:

1″ Filters – Monthly
2″ Filters – Bimonthly
3″, 4″, and 5″ Filters – Every 4 to 6 months

When in doubt, swap it out!

How do you remember to change it?

You can get a thermostat that will remind you. I personally use my calendar in my phone to remind me. Just make sure you do it! It’s something so simple to maintain that, if neglected, can cause you thousands of dollars in the long run!