Where Is My Furnace Filter Located? (3 Easy Steps)

Do you need help in finding your furnace filter?

A common client question during one of my home inspections is the location of the HVAC filter (here is my review on the best washable furnace filters to save money.)

In this guide, I will go over...

  • How to find the filter at your furnace
  • Common places to find return filters in the ceiling or wall
  • Why it's sometimes required to remove the furnace cover to access the filter

Let's get started with this guide!

where is my furnace filter located

#1. Inspect Your Furnace

The most common place to find your HVAC filter is going to be at the furnace (here is my guide on locating your filters).

It will be located on the return side of the furnace, this is where air is going into the furnace to be heated or cooled.

Look for an opening or slot where you can see the edge of the filter. Quite often, there is a metal slot cover that you will have to open. Sometimes there is a magnetic strip that is covering the AC filter slot.

If you still don't see a filter, you may have to actually remove the cover of the furnace to access the filter. But before you take off the cover, it is time to carefully look around the home --- because the filter may be in a ceiling or wall vent.

Read Also: What Are The Best Washable And Reusable Furnace Filters?

#2. Carefully Inspect The Ceilings And Walls

I would say around 30% of homes that I inspect have their furnace filter in a ceiling return vent. The return vents are the much larger vents that send air back to the air handler through the return duct.

The supply air vents are sending air into your bedrooms and are much smaller --- the standard size is 12" x 6".

In contrast, the return vents are large enough so that a standard furnace filter can fit inside. Some common sizes are 20" x 20" and 16" x 25".

Read Also: What Are The Best Furnace Filters For Dust Control?

I would carefully look at all the ceilings for a return vent, and check to see if there is a filter inside. In addition to the ceilings, there may be 1-2 return vents in the walls.

If there are air conditioner filters in the return vents, then there shouldn't be a filter at the furnace --- even though sometimes there is.

Technically, there should only be a filter at the furnace or only a filter at the return vent. And if the filter is at the return vent, then all of the return vents should have filters.

Some homes I inspect have 4-5 different A/C filters and all at the return vents.

In addition, when return vents have furnace filters, the vent cover should have a latch so that it can be easily opened in order to change the filter. After carefully inspecting the larger return vents for filters --- and they are all missing --- then move on to the next step.

Read Also: How Often To Change A 1-Inch Furnace Filter?

where is my furnace filter located (1)

#3. Take Off The Furnace Cover

Well, you inspected the furnace exterior and you didn't see a filter. You walked around the home, looked at all of the return vents, and didn't see any filters. There is only one last place to check --- inside of the furnace.

For whatever reason, design stupidity, or whatever you want to call it --- sometimes the furnace cover will have to be taken off just to change the AC filter.

With some furnaces, like American Standard models, it can be very easy to remove the front cover. However, with other brands, it can be a nightmare to take off or to put it back on --- hopefully you won't have that problem.

Read Also: How To Clean A/C Filters?

The most common screws holding furnace covers are hex nut self-tapping screws. You will need a nut driver bit or tool to remove these hex screws.

Before removing the furnace cover, it is a good idea to turn the furnace off by using the emergency switch in the utility closet or by turning it off at the thermostat.

After removing the screws, or latches, and possibly removing some of the metal sealing tape --- carefully remove the cover. The air conditioner filter should be there... likely in a filter slot or being held by some wiring.

Read Also: What Are The Best Air Conditioner Filters For Allergies?

where is my furnace filter located

Final Thoughts On Locating Your Furnace Filter

Well, there you have it --- my 3 step guide to locating your HVAC filter.

Most homes are pretty easy to locate the filter, but once in a while I inspect a home where it can take quite a while just to locate the filter. Either way, the filter will either be in the return vent(s) or at the furnace.

And once you located the HVAC filter, make sure to change it at a minimum every 90 days (though I change mine every 30 days due to allergies). Also, make sure the filter is snug in the filter slot, you don't want air passing around the filter.

Remember that up to half of a home's energy is taken up in the HVAC system, so changing the filter regularly is important for HVAC maintenance.

Read Also: What Are The Best Furnace Filters For Odors?

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