Flap above aircon filter - position?

[whazzatt]

Hi

I just replaced the air conditioner filter in my 2006 yaris. Well, replaced is the wrong word, because there wasn't one installed!

I followed the instructions from a youtube video to do the quick and easy filter 'change'. In the video I followed, the flap above the aircon filter is up.

In other videos, the flap is down.

In my yaris, the flap was mid-way between up and down!!!

I've never been happy with the performance of the aircon, so I'm wondering what your thoughts are on how to position the flap.

I am happy to test to see the difference, but maybe someone has thoughts or experience on this.

Pictures attached.

Thanks