Yaris MK3 pollen filter airflow direction

[v1nny]

Hi all. I've got a 2012 Yaris MK3, and it's service time. I ordered a replacement pollen filter as it looked easy to do myself. On the plastic bracket piece, the 'UP' arrow was pointing up. Fair enough. But the existing filter had the 'Airflow' pointing downwards 😕

Just want to double check it was installed correctly before, and I should follow that? Here's a picture of me holding the new one. Should it flipped so the 'Airflow' is pointing downwards?

Many thanks for reading 😀

 

[flash22]

air is pulled in from the top, so air flow is down

[v1nny]

26 minutes ago, flash22 said:

air is pulled in from the top, so air flow is down

Thanks flash22. I've just installed the filter with the airflow arrow pointing down as advised. Kind regards

[Cyker]

That's going to be confusing... I'll have to double-check whether the arrow is an orientation arrow or a air-flow direction arrow when I start having to change mine myself!!  

Is it obvious which side is the 'in'-side and which side is the 'out'-side on the filter, or does it look the same on both sides??

This is one thing that was good about the Mk1 - It had a carrier so it was physically impossible to install it the filter the wrong way! It also sealed the filter better - The current design I can see air bypassing the filter around the sides as there's no seal or anything...

 

 

[MikeSh]

40 minutes ago, Cyker said:

I'll have to double-check whether the arrow is an orientation arrow or a air-flow direction arrow

Usually it will be an airflow direction.

These filters are often generic and may be used in different cars and indeed other equipment, so the air could be flowing up, down, sideways or at an angle. So an 'up' arrow makes no sense.

Of course a typical mechanic will think it's 'up' 🤪

[bathtub tom]

Arow down if it says airflow, arrow up if it says up. My MK3 had the filter installed the wrong way (arrow and UP printed on it pointing down) by Toyota main dealer. Air con improved no end since I fitted a new filter the correct way round.

[MikeSh]

Yes, if it actually says up, probably on a Toyota part where the application is defined, then do that.

For generic parts if there is no text, just the arrow, it should be airflow. But I'm sure some will be vague or wrong.

[flash22]

The blower motor sucks air in the top pulls into the centre of the squirrel cage, it is then blown out to the edges and force into the heater box

the speed control  "resistor" is in the air flow before it goes into the heater box to aid cooling

[TonyHSD]

On 8/10/2022 at 12:37 PM, v1nny said:

Hi all. I've got a 2012 Yaris MK3, and it's service time. I ordered a replacement pollen filter as it looked easy to do myself. On the plastic bracket piece, the 'UP' arrow was pointing up. Fair enough. But the existing filter had the 'Airflow' pointing downwards 😕

Just want to double check it was installed correctly before, and I should follow that? Here's a picture of me holding the new one. Should it flipped so the 'Airflow' is pointing downwards?

Many thanks for reading 😀

 

This filter should be placed upside down, with letters pointing downwards. Here it’s how should be installed. My filter is different make and arrows match installation orientation and letters. 👍

[bathtub tom]

THAT IS NOT UPSIDE DOWN, THAT IS CORRECT FOR THE AIRFLOW!

Yes, I know I had caps lock on!

[TonyHSD]

50 minutes ago, bathtub tom said:

THAT IS NOT UPSIDE DOWN, THAT IS CORRECT FOR THE AIRFLOW!

Yes, I know I had caps lock on!

I meant with letters upside down in his particular case and filter. Anyway, it’s so easy and nothing complicated. 👍

[MikeSh]

4 hours ago, TonyHSD said:

I meant with letters upside down in his particular case and filter.

But the letters aren't upside down ...

 

Oh, hang on. Which picture are you talking about?

Edited August 13, 2022 by MikeSh
Clarification?

[bathtub tom]

7 hours ago, MikeSh said:

But the letters aren't upside down ...

 

Oh, hang on. Which picture are you talking about?

The one posted Wednesday at 12:37 PM showing a Borg & Beck BFC 1021

[Guest]

Air flow arrows or an UP arrow isn't needed anyway, but obviously help (certainly for some Toyota "technicians"!), the end of the filter medium pleats are on top/up.

As in Tony's pic.. Or incorrectly in the Borg & Beck variant, as already pointed out in previous posts.

[bathtub tom]

11 minutes ago, mrpj1 said:

 the end of the filter medium pleats are on top/up.

I don't know what you mean by that. I haven't examined one minutely, but they look the same to me both sides.

[Cyker]

I think my Mk4's is the same, although I haven't looked at it properly, just to check if they'd changed it! If it weren't for the writing I don't think I'd be able to tell one side from the other, unlike the Mk1's filter which was completely different on both sides and would only go into the carrier one way.