Windscreen Condensation
 

I've noticed recently that when the car (07 A8) is parked up that there's usually a lot of condensation on the interior windows. I've had my mechanic clean out the drains and they were pretty blocked all right and that sorted out any leaks coming from the sun roof. Still a good bit of condensation tho. So, if I open the windows and clear that off...I'm usually OK...

However, when i'm driving 1st thing in the morning and if I turn on the A/C to windscreen it totally fogs up, like in an instant. I had to pull over the other morning as I literally couldn't see out. It was like that for say 3-4 minutes until the car heated up and then it cleared. But it happens now most times when I turn it on. It's as if there's water trapped somewhere in the A/C system...

I can resort to perhaps dehumidifyer crystals but just wondering if there's something else I should be looking at? Any ideas lads?

Mine does it too, seems to do it less on LO than on HI. I think the evaporator is still wet from the day before and then it makes the incoming air damp.

Yes mine's often like that even when drain are clear, though it is a D2. I think there's plenty of residual humidity in the cabin materials as well as lurking in the HVAC system.
I do recall as and when I've used dehumidifier bags it pretty much disappears.

I've had the same thing with this car and also in my two S4s, doesnt happen in the summer mind, so I guess its moisture thats been brought into the car from wet shoes and stuff

...or a leaking rear windscreen seal :mad::mad:

Where you say 'clean out the drains ' ...... so engine bulk head drains , sunroof and air con evaporator drains ?

Thanks Lee, no i just had the sunroof drains cleaned...not the air con drains...this might indeed be the problem...i'll go inspecting this evening....