Maintenance installed an AC filter that is too small
An ill-fitting or incorrectly sized replacement air filter can leave gaps, potentially causing throat irritation for apartment residents. It can also raise safety worries about whether the improper fit might cause a fire or damage the system.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
Maintenance installed an AC filter that is too small
- 1putting the slightly mis-sized filter in at an angleDid this help you?
- 2forcing the filter to fit as long as the door goes back onDid this help you?
- 3Cutting a smaller filter to size and duct-taping it to the first filter to fill the remaining gap in the track.Did this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“In getting a replacement filter this year I realized only once I was going to put this in that it was an inch wider than our previous filters.”source ↗
“I just don't want to cause a fire in the house or any big trouble like that.”source ↗
“A couple of the paper pieces did break is that also going to be a problem?”source ↗
“Hello, maintenance just replaced our AC filter and both people living in the apartment are having throat irritation. Not sure if this could be causing it, but it seems like the filter replacement is too small. Is it too small?”source ↗
“Thank you for this I was stressed because this was always the kind of filter we put in it 😭”source ↗
“I DoorDashed air filters (first mistake) and they gave me two 16x20 instead of two 20x20.”source ↗
“The 16x20 fits securely width-wise between the tracks, however there was a four inch gap at the top. I cut the other filter to size and duct-taped it to the first filter to fill the gap.”source ↗
Where this came up
People with this problem also raised
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- 3Gasket coating chipping off during cleaning
- 2Why are AC register filters clogging every week?