Climate Control Troubles

[Tony Hoffman]

> I have a late 1990 Audi 100 TQ Sport

> The problem seems to be that the system is very fond of blowing hot air into to passenger compartement. It even blows hot air through the centre vents. I thought that hot air was supposed to exit through the nozzles on the front window and the footwells. That's at least how this system worked on my very early 1986 Audi 100 Quattro.
> Anyhow, back to hot air problem.
<snip>

I believe it only does this when on defrost. Although, I seem to
remember the V8 blowing some air toward the W/S, even in auto.
Although, that was only in heating mode, not cooling. And, it has been
some time since I've driven it.

<snip>
> If I drive along and set the temperature to 24 C and it's 13-14 C outside, it starts to heat the passenger compartment up - through the center vents - like there is no tomorrow. It heats and heats and heats and although I'm kind of frozen I start to sweat! I have to turn it down to 20-21 C for it to cool. Anything above that, it only heats.
<snip>

At some point in time, is should sort of level out, and switch to low
fan and just slight heating. That is, when its very near the preset
temperature. Are you saying it continues to heat like crazy, till you
get it to cool? As in, there is no middle ground?

 When you are setting the temp to 24, that's pretty high for an
average person to be comfortable. 21 is a lot closer to where most of
us keep their houses. So, as far as the car heating the passenger
compartment, it sounds pretty accurate. But, that all depends on just
how hot it gets before you turn it down. For, instance, when normal
driving, I set the V8 at about 68-70F. That is, about 20-21C. If I set
it higher, it will heat the cabin beyond what is comfortable for me.

<snip>
> If I set the ECC to 25 C it seems to direct the air up to the front window and footwells. The Bi-Level function works. I run the ECC in ECON-mode for the time being, since there is no need for the AC-compressor to run yet due to the temperature, but I have tried to run it in AUTO-mode; no change.
<snip>

The only other thing I can suggest is if it still seems off to you,
you may want to pull the resistance values from the interior
temperature sensor, and make sure the fan on it is working. If not,
the climate control is not getting the correct reading, and will not
heat correctly. For instance, if the fan on it isn't running, it will
stay fairly cold, along with the other complnents in that are of the
dash. So, it will think the car is cold inside, even though it may be
close to the set temperature.

Tony

> I hope someone here can help me resolve this :)
>
> /Dag
> 1990 Audi 100 TQ Sport Exklusiv