Furnace filter airflow

[Blizzard]

Came across this today when my ductwork was getting cleaned. I'm confident this is correct. We use 3M filtrete filters. On many of the Filtrete filters the airflow arrow is backwards. The mesh on the outside of the filter should be next to the blower compartment on your furnace. That protects, hopefully, the filter from being sucked into your furnace if it collapses. Usually, you just line up the airflow arrows and you, or at least I, wouldn't give it a second thought. The mesh on some of these Filtrete's is the opposite direction. If you're using them you may want to give it a check to be sure it is correct because mine was not.

Yes, the wire mesh on a furnace filter should be installed facing the blower motor:

• Purpose
  The wire mesh provides strength and rigidity to the filter so it can catch particles. It also prevents the filter from collapsing or damaging the blower if it gets dirty.

 

[gopherbadgerman]

I buy the cheap one dollar ones so there is less restriction. I dont think it matters on those what direction they face?

 

[Blizzard]

I buy the cheap one dollar ones so there is less restriction. I dont think it matters on those what direction they face?

Yes, we used to do that as well. The guy who did the install of my newest furnace, I'm on my 3rd in 30 years, which sucks because in our old house that furnace was probably original and was working great when we moved in 96 and the house was built in 55, anyway, for airflow the cheap filters are by far the best. My wife has got bad allergies, the better filters help quite a bit.

 

[short ornery norwegian]

not being a mechanical guy, I just go by the instructions on the package. on the filters I buy at Ace Hardware, it clearly shows that the arrow is supposed to point inwards - or in the direction of the burners - as opposed to outwards, or in the direction that the air travels upwards and into the rest of the house.

to be clear, I had over-looked the instructions in the past and was installing the filters backwards - at least backwards of what the instructions say.

and then they recommend replacing the filters every 3 or 4 months. when I checked mine at the start of heating season, the same filter had been in there for a year............hey, I am not the DIY guy.

 

[GophersInIowa]

I buy the cheap one dollar ones so there is less restriction. I dont think it matters on those what direction they face?

We do the same thing. When I put in the more expensive ones, it would get all bent up so was told to get the cheap ones.

 

[Breakin' The Plane]

My furnace has $30 behemoth filters (6" thick). They aren't getting sucked into the furnace. I've been told always point the arrow toward the furnace.

Furnace was new last year. Before the old one went to greener pastures, I had two clubs in my bag if it wasn't kicking on: change the filter, or clean the flame sensor. Luckily those both always worked.