Said It Here

Where is the air filter slot in this house?

HVAC air filters in new or unfamiliar homes are often hidden away or missing from the return grates entirely, leaving homeowners scouring the house with no obvious place to install one. This makes it impossible to figure out the correct setup or even know if a filter is missing altogether.

What people tried

Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.

  1. 1
    leaving the unit without a filter
  2. 2
    making custom filters to sit on top of the coils
  3. 3
    Searching near the blower unit for alternative filter placements
  4. 4
    Measuring the existing washable filter to replace it with a standard disposable one
  5. 5
    Searching ceilings or walls for large return vents that hinge open
  6. 6
    Getting a cheap HVAC inspection done to have professionals point out filter locations
  7. 7
    Checking both the wall return vents and the air handler unit to locate the filter slot.
  8. 8
    Searching different potential compartments on the air handler
  9. 9
    Measuring the filter slot manually with a tape measure
  10. 10
    Checking for separate return air grill filter locations

In their words

Unedited, most upvoted first, each linked to the thread it came from.

for the life of me I can't seem to find where the hell the air filter should be.source ↗

I have scoured the house for a spot that seems like it would house the filter to no avail.source ↗

incredibleanderson · r/hvacadvice · 6 upvotes

What I Don’t understand is they gave me a 16 x 20 filter and it doesn’t seem to fit on either side . Both vents have 16 width but not 20.source ↗

Frequent-Net6508 · r/hvacadvice · 3 upvotes

I do know there is suppose to be a filter some where here and I can’t find one or a place for one.source ↗

saint_penjs · r/homeowners · 2 upvotes

I recently bought my Grandma’s house and noticed there’s no filter on the return grate in the house.source ↗

Is this possibly the only filter location, or could it be designed to run with 2 filters in line?source ↗

Ohpluto_Mypluto · r/hvacadvice · 2 upvotes

The spot on the wall is just open into the top of the furnace. Would just putting a filter there be acceptable?source ↗

saint_penjs · r/homeowners · 1 upvotes

Hi! First time homeowner here. I went into my attic today to replace my hvac filter but I have no clue where it is.source ↗

Adventurous-Hat-4217 · r/hvacadvice · 1 upvotes

I have a new house that I’ve built and I got my HVAC installed about three months ago I just noticed that he never put in a filter because this fuse box is pretty dusty.source ↗

I tried to take the screws off, but it’s pretty tight on there. Anything you suggest I do? Obv put in a filter .source ↗

Frequent-Net6508 · r/hvacadvice

Where this came up

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