When changing out your furnace filter for a new one, do you ever wonder if you are installing it the correct way? Believe it or not, there is a right way and a wrong way to change your AC filter. The air flow arrow is the key!
Locating Your Air Filters
In most cases, you should have one air filter for each level of your house. Finding where you air filters are located is extremely important. Sometimes they can be in your furnace, ceiling, or in the wall.
After you’ve located where your filters are, you’ll need to find the size you need and figure out which MERV rating best fits your needs. Need help? Check out these blogs for help:
How To Safely Change Your Air Filter
Once you’ve figured out the size and MERV rating you need, it’s time to get ready to change your furnace filter. Here’s a quick video on how to safely change your air filter:
Don’t forget! Turn off you HVAC system while you are changing your air filter.
If you inspect your new air filter, you may see an arrow that says, “Air Flow”. Here’s an example:
Which Way Should The Air Filter Arrow Point?
When changing furnace filters many people wonder where the arrow on the filter should point. The arrow should always point in the direction the air is flowing.
Here’s an easy way to figure out which way the airflow arrow should point: The arrow should ALWAYS point towards your return or furnace. The pleated part of the filter should be facing you when you install it. The other side, which usually consists of a metal mesh or cardboard frame, should be pointed towards the return.
Once you’ve properly installed your furnace filter, you can close the metal grille grate and turn your HVAC system back on.
Time to order furnace filters? We’ve got you covered!
Wish there was an easier way to remember what size air filter you need and when it’s time to change it? Sign up for our Home Filter Club filter subscription service! Just find the filter you need, subscribe, and save!
Have a question about furnace filter installation? Drop in the comments below.
Brandon says
Hello Vicky, thanks for reaching out! The arrow on your air filter should point towards your furnace.
Vicky Helsel says
My air filter goes in the bottom of the furnace. Should the arrow point up or down? Thank you, vicky
Brandon says
Hello Ed, since you have a different design than our standard filters, we’ll need some more information to assist. If you could find your part number and contact our customer service team via e-mail, [email protected], they’ll be glad to help you further.
Ed says
I have a metal reusable filter. No arrow on filter? How do I know what side goes toward air flow? Thanks Ed
Brandon says
Hello Sheila, thanks for your comment. Usually the arrow is going to point toward the furnace, although the direction of the air flow can affect this. To be certain, we would need more detailed information about your furnace design. Please contact our customer care team at [email protected] for additional assistance in installing your filter.
sheila elliott says
Hi my filter vent is on the floor under the furance unit I take off the top door then the bottom. So which way should my arrow be facing. Right now I have the arrow facing up toward the unit. Thank you have a blessed day
Katie says
Michael,
Thank you for sharing that great tip!
Michael says
One way to check the air flow while your unit is running is to take a plastic bag (like you get at Walmart) and hold it up to the grill. If the bag is sucked in towards the grill, that’s the air flow direction.
Katie says
Hi Chelsea, great question! Unless the manufacturer of your filter says otherwise, the arrow should always point toward the furnace.
Chelsea says
My arrow points the opposite side the metal mesh is on so the metal should be on the furnace side not facing me?
Katie says
Cynthia,
Thank you for your feedback. The filter arrow should point toward your furnace system as it slides in.
Cynthia Tier says
None of this helped me. My air filter slides inside the furnace not on the outside of it. I still don’t know which way the filter arrow goes. Up or down. Nobody seems to know. I’m sure I’m not the only one with a furnace like this.
Katie says
Kristee,
We are so happy to hear that you found this blog post helpful! If you have any questions when it comes to air or water filtration we are happy to help!
Kristee Nassar says
Omg thanks! First time putting in an air filter. Newly single mom and just moved into an apartment. Didn’t ever have to worry about things like this because my husband always took care of em.
Katie says
Ken,
Thank you for reaching out to us. We asked our Air Filtration Expert to weigh-in on this and here’s what she recommended: Make sure you have a filter in each return. Perhaps start with a 1″ MERV 8 to see if that offers the improvement you are looking for. She also recommends adding room air purifiers to help improve the overall air quality.
Ken says
When I built my home 20 years ago my heat pump, duct..all were installed then. There were two return vents installed in the hallway that had 1” pleated filters in. 4 years ago I had to replace that heat pump with a new American Standard. That company installed me a 16x20x4 filter in the return just before the return to the handler. I use a Mer 13 and change it about every 8 months. The filter says a year. There is dust that gets in the hallway returns before reaching the filter near the handler meaning the return duct gets a lot of dust before ever getting to the filter. Can I put some kind of thin filter in the hallway returns to catch some of that house dust before it gets to the filter back before the handler? Could that be to much restriction? Any other options? Don’t like the idea of all that dust going into the hallway return bents before it travels 20 ft to the 20x16x4 filter before the return to handler?
Katie says
Andy,
You are absolutely right, I do live in the south and do not have a basement. I have also seen air filters installed next next to the furnace, but now you have my wheels turning as to what the differences are. This is really interesting!
Andy Murphy-Young says
I’ve never seen a place where you put the air filters in the wall intake like that. They have always been in the basement next to the furnace. Do you live in the south where their aren’t basements or use a different type of HVAC?