Cabin filter: wrong indicated flow direction

[Quattro Pete]

I cheapened out this time around and bought some no-name charcoal cabin filters.

They came as a 2-pack in the same box. I noticed one of them has the wrong indicated flow direction printed on the outside. Both of them should be pointing up in the below picture.

Is this just marking error? Or does flow direction actually matter with these charcoal filters and I should send it back because the filter was somehow manufactured wrong? I've seen some inconclusive opinions on this in the past.

My guess is they just stamped the markings wrong on one of them.

 

[BMWTurboDzl]

IMO the filter media was installed in the cage incorrectly and the arrow is just intended to assist with making sure the filter is seated correctly in the air box due to the presence of the tabs.

My WAG

 

[atikovi]

Unless it restricts air flow I wouldn't worry about it much. Maybe check on it or change it sooner. What brand is that? I can get name brand Denso, Nippon or TYC for $6 to $8. Made in China too but by a reputable manufacturer I assume.

 

[Quattro Pete]

Originally Posted by atikovi
What brand is that?

OPparts sold by AutohausAZ:
https://www.autohausaz.com/pn/81906031

I usually buy NPN which are more expensive.

 

[Yah-Tah-Hey]

That air flow arrow has generated more than a few questions about just how to install the cabin filter. On my Toyota, the air filter is positioned above the blower motor so the air flow is down, no matter where the arrow points.

 

[KGMtech]

Yeah, the arrow on these things is mostly to confuse, and address those who are so cheap that they tap and replace the old one, preventing a facefull of leaf debris in your face...

 

[atikovi]

NPN is good too. Beck Arnley $16. https://www.rockauto.com/en/catalog...;+air+conditioning,cabin+air+filter,6832

 

[Quattro Pete]

Originally Posted by atikovi
Beck Arnley $16. https://www.rockauto.com/en/catalog...;+air+conditioning,cabin+air+filter,6832

The Beck/Arnley one is not charcoal, hence the low price.

 

[atikovi]

Looks like it has charcoal from the picture.

 

[Quattro Pete]

Originally Posted by atikovi
Looks like it has charcoal from the picture.
Yeah, it does look like that, even though Rockauto has it listed in Standard (non Carbon) section.
Beckarnley.com doesn't specify one way or the other.

 

[purelux]

If there's no activated carbon it wouldn't be as much a deal. But I've seen this on home hepa filters installed wrong and the charcoal got all over the blower.

 

[Kira]

Which car are these filter elements in?

Is a picture including the old ones side-by-side with the new ones possible?

 

[Quattro Pete]

Originally Posted by Kira
Which car are these filter elements in?

Is a picture including the old ones side-by-side with the new ones possible?

BMW 530i.

Sorry, I already threw away the old filters, but they were pretty much identical to the new ones, sans the incorrect marking on one of them.

According to AutohausAZ, the writing was printed upside down.

 

[purelux]

What it could do if it's a progressively finer filter layers it would be the opposite and load up faster and restrict the air prematurely.