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

[ex-x-fire]

Isn't that for outside air or recirculated air?

[whazzatt]

Originally Posted by ex-x-fire

Isn't that for outside air or recirculated air?

I don't know! But that would make sense. If it is, then it looks like up would mean re-circulated air, and down would mean outside air.

I'm still not sure if I should leave it up or down. I anticipate the reply, "up if I want re-circulated air, and down if I want outside air", but this would tell me little about the pros and cons of either position.

The person who fiddled with it before me must also have been unsure, seeing as they left the flap in the middle position!

[thetut]

The position of that flap should be controlled by the outer ring of the fan speed knob.

If it does not move when the control is used then the mechanical connection has come undone.

Remove the filter and check it out.

[kevinj93]

Generally, recirculating the air will provide better cooling rather than drawing in hot, outside air. Of course, if the Yaris has heat soaked, sitting in the sun, the outside air will initially be cooler. My normal procedure if the car has been parked in the sun is outside air until the cabin starts to cool, then switch to recirculate.

My understanding (and I may be wrong) is that the recirculated air will be cooler than the hot fresh air, and the air condityioner does not have to work as hard to keep it cool.

[whazzatt]

Originally Posted by thetut

The position of that flap should be controlled by the outer ring of the fan speed knob.

If it does not move when the control is used then the mechanical connection has come undone.

Remove the filter and check it out.

I feel quite silly for not having checked the outer dial knob - it makes perfect sense that it controls the 'flap'.

Yes, I turned the dial, and it does move the flap.

Interestingly, the position that I found the flap in - i.e. halfway between open and closed - is the position that the flap is placed in by turning the dial all the way to re-circulated air. This explains why, whenever I have tried to close access to the outside air when driving on gravel roads, the inside of the car still gets dusty.

On further fiddling, I found that if I turn the dial from outside air to re-circulated very quickly, almost too quickly, enough momentum is created to push the flap all the way to the 'up' position that closes off the outside air flow.

This would explain why I found the flap in half-way position when the dial was set to re-circulated air.

At least I know this now. I have to turn the dial with force if I want to block outside air completely.

[whazzatt]

Originally Posted by kevinj93

Generally, recirculating the air will provide better cooling rather than drawing in hot, outside air. Of course, if the Yaris has heat soaked, sitting in the sun, the outside air will initially be cooler. My normal procedure if the car has been parked in the sun is outside air until the cabin starts to cool, then switch to recirculate.

My understanding (and I may be wrong) is that the recirculated air will be cooler than the hot fresh air, and the air condityioner does not have to work as hard to keep it cool.

Good advice, thanks

[komichal]

General advice is - when you want to drive somewhere and the car is incredibly hot and even hotter inside - to open all doors and let the wind and nature cool the inside as much as possible. After a minute or two you can start the AC and let the air circulate internally - only after a few minutes (when the vents actually start blowing the cool air and the internal space starts to cool off) you can consider switching to external air.

The AC unit in Yaris is quite weak I must say. The dealership checked the coolant, the pressures, the compressor - everything OK. But it takes ages in hot summer to cool the internal space. I wonder if the more southern regions received some more powerful AC because in hot days in Central Europe the AC is almost insufficient.