Difficulty de-misting

[patomlin76]

This evening was surprisingly much colder than the last few, and so when I got into my car after a short walk, I started the engine and turned the fans on. However whether it was due to my breathing or the sudden rush of fan air, the whole car pretty much misted up, heavily, in seconds. It took best part of 10 minutes for the ventilation system to start clearing parts of the windows.

Is this a sign that the pollen filter needs replacing, or my air conditioning needs servicing? There is no water or moisture in the car - checked in all the usual places (i think), but it was certainly clear before I entered the car.

Thanks for any help!

[rapport25]

This evening was surprisingly much colder than the last few, and so when I got into my car after a short walk, I started the engine and turned the fans on. However whether it was due to my breathing or the sudden rush of fan air, the whole car pretty much misted up, heavily, in seconds. It took best part of 10 minutes for the ventilation system to start clearing parts of the windows.

Is this a sign that the pollen filter needs replacing, or my air conditioning needs servicing? There is no water or moisture in the car - checked in all the usual places (i think), but it was certainly clear before I entered the car.

Thanks for any help!

I have found if I get in the car and Mrs Rappy has damp hair the car will tend to steam up pretty quick. Not sure if its to do with dual climate as my previous car had climate control but never seemed to steam up like the passat does.

Also If you cars heating is set to recirculate this will steam up the car. On my previous car it was steaming up all the time and the recirculate flap had jammed shut. But as you stated it cleared it. So its not that.

When was the pollen filter changed last? I would suggest every 20k

When was the a/c regassed last? I would suggest every 3 to 4 yrs

Hth's

Rappy.

[PeteK]

I don't think the A/C actually works below a certain temperature, I think it's about 5C from memory?

[Quatrelle]

The other thing is to make sure the glass is clean (on the inside!). By clean I mean get rid of what seems to be an invisible film, especially for the rear window. The screen gets the usual 'plastic' degeneration that afflicts all modern cars.

[rapport25]

The other thing is to make sure the glass is clean (on the inside!). By clean I mean get rid of what seems to be an invisible film, especially for the rear window. The screen gets the usual 'plastic' degeneration that afflicts all modern cars.

X2 ;):Blush:

[Quatrelle]

x2 ;):blush:

Stop it, people will start talking:Blush2:

[patomlin76]

Thanks for the help...

The air conditioning has never been regassed and the car is 6 years old. Probably wouldn't explain the quick misting up, but is something I will look at in the summer when its easier to tell how cold it can get..

Pollen filter is really easy to change and has been nearly 20k since it was last changed.

And finally I will look at cleaning all the interior windows - something I have rarely done!

[Teflon]

Run the aircon.

Cars nowadays are very well sealed. In this weather the carpets and upholstery hold moisture, especially after you have entered the car with a wet coat or shoes. It doesn't get the chance to be removed from the cabin. The carpets don't need to feel wet, it takes very little moisture. As you drive you are releasing lots more moisture as you breathe.

You drive - the car warms up and the cabin air holds increasing amounts of moisture. When you get out it all cools down. In the right condition, the cabin air is cold and close to the dew point of the moist air. Next time you get in, you either bring more moisture (Mrs Rappy's hair, or just from your breath) or else you let a slug of even colder, damper air into the car.

Result - instant condensation on the coldest part of the interior, which is invariably the windows. You need to run the aircon all the time, and it will dry out the cabin air, pulling moisure from the carpets in the process. The alternative is either a big bag of dessicant on the rear parcel shelf or else stop breathing and drive naked. It also helps if you can teleport into the car Star-Trek style to avoid moist external air rushing inside on very muggy days.

Another option is to throw a big lump of dry ice into the car and the moisture will condense close to it. This is only safe if you can survive by breathing carbon dioxide.

[patomlin76]

To be fair, the air con could probably do with a service and re-gas which I may get done this summer, however I'm getting a pollen filter this lunchtime as I believe this can really degrade performance of the aircon/venting system.

Thanks

[bigstuff]

Undoubtedly moisture related.

Could just be wet feet but worth looking in wheel well to ensure theres no water in there.

[PeteK]

My B5.5 Passat also steams up if there are a few people in the car and particularly if it is damp or wet outside. When the aircon is switched on, it always clears within a minute or so. However as I mentioned above, the air con compressor will not engage in temperatures below 4C (have a look on Google, this applies to all cars not just the Passat) rendering the air con inoperative. As soon as the temperature starts to rise again, i'm sure you won't have any issues.

[patomlin76]

Very helpful post PeteK...

I have ordered the pollen filter which will have needed replacing anyway, and will also double check the spare wheel well, just to make sure there's nothing in there. However I'm sure standing water like that would also make the car steam up even when empty, and this isn't happening to me...

Thanks