Very strange air-con problem...

[Brad89]

Hi all,

The following problem is very intermittent (occurs once every few weeks) But im afraid it might get worse towards the winter!
Sometimes when i switch the air-con onto auto its starts up as normal but within 5-10 seconds the WHOLE of the windscreen and drivers windows completely mist up!
This one has left me completely stumped because i can think of no logical reason behind it.
Anyone else had this problem or knows whats going on?

 

[Staz]

This is pretty normal. It's just because of different temperatures reacting. All you need to do is press the window clear button and wait a bit.

What time of day is this happening and where is you car parked?

 

[Brad89]

Sorry about my impatience!

Tends to happen at night when its fairly chilly outside & i stick it on 22, 23 auto. I kno that the quick difference in temps is an obvious answer but i was just surprised how it can mist up so quickly. Usually when the cars warm too. I think ive just answered my own question haha

 

[Staz]

Yeah in that case there's not a problem. It happened to me last Saturday when I got back into my car at night.

 

[pluves1]

Best advice I can give is try and leave your air con on auto all the time. Misting rarely seems to happen in all the cars I've had when I do this. However, if its particularly damp and or humid you're always going to get some kind of misting.

 

[Englishguy]

Hi all, This happened to my A3 a few times. After removing the pollen filter and replacing/cleaning I havn't had any more probs. Obviously make sure resurc is off initially. Ensure that drain tubes are clear and draining effieciently. Hope this may help.....

 

[Staz]

I have brand new pollen filters and mine did this friday evening.

 

[PW-Motorsport]

This is normal as suggested above.

The evaporator (cooling bit) in the air box will trap/freeze moisture on the evaporator as the air passes though it. When the car engine is shut down this frozen water moisture will thaw and drain out through the air box drain. When the car is restarted the some moisture in the air box will be blown up on to the screen. Hence the steam.

Hope this helps....