Author Topic: Windows steaming up every time it rains  (Read 8065 times)

Offline Exonian

  • Serious forum addict
  • *
  • Posts: 9,292
Re: Windows steaming up every time it rains
« Reply #30 on: 28 June 2015, 13:41 »
I'm with snooze on this. I just feel it causes more problems than it cures. The odd time i have used it it seems to have taken 2 or 3 runs to get rid of the dry air.

Its definitely changed days in the A/C world as I remember with one of my first few cars that when I put the aircon on, I could actually feel a drop in the cars accelerating. Not to mention the fuel guage dropping like a ton of bricks.

On a small capacity normally aspirated car you can't half tell the air con is on, the thing loses about 50bhp when the compressor kicks in!  :laugh:

My first car with air-con was an Ibiza TDI. The climate control on that was a bit primitive to say the least, it was obviously designed for Mediterranean heat rather than English "can't make up its mind" weather. I remember getting in that car when it was about minus four outside and flicking the 'ignition' on to be greeted with a hurricane of freezing air in my face! That woke me up!
‘25 8.5R, ‘23 8R, ‘20 8CS, ‘19 135iX, ‘19 TCR, ‘17 Ed40, ‘17 GTD, ‘15 7R, ‘13 GTI PP, ‘11 GTI, ‘09 GTI, ‘98 Ibiza Cupra, ‘05 GTI, ‘06 Polo GTI, ‘04 GT TDI, ‘05 Fabia vRS, ‘02 GTI T, ‘03 Ibiza TDI 130, ‘01 Leon 180, ‘89 mk2 16v, ‘99 Ibiza TDI, ‘96 VR6, ‘98 Ibiza TDI, ‘92 VR6, ‘88 mk2 8v, ‘92 Polo G40, ‘91 mk2 8v, ‘89 mk2 8v, 205 GTI 1.9, ‘83 mk1 GTI, ‘80 Scirocco GTI, plus some others I’ve forgotten 

Offline monkeyhanger

  • Serious forum addict
  • *
  • Posts: 6,663
Re: Windows steaming up every time it rains
« Reply #31 on: 28 June 2015, 18:04 »
Air con off, heaters on full wack. Having the air con on just draws moist air in to the car compounding the problem.

On several occasions I've got in to my car on a cold damp morning with air con on and what was a nice clear windscreen then mists up instantly.

Aircon always helps in demisting my windscreen in the winter. The aircon dehumidifies the air coming into the cabin so that it doesn't have any moisture to condense when the air hits the cold windscreen. Humidity hitting cold surfaces is what causes condensation.

In the winter you have two options to avoid condensation - warm up the windscreen enough so the moisture in the drawn in ambient air isn't condensed on it, or dry the air hitting the windscreen with the aircon - albeit the aircon won't be massively effective drying the air while sat idling after you have just started the car - it will draw in wet ambient air for a very short while.

Whey ya bugger! It's finally arrived after an 8 month wait....
MK7 R 5 door, manual, Lapiz Blue, Prets.

Offline Mark V GTD

  • I live here
  • *****
  • Posts: 1,292
Re: Windows steaming up every time it rains
« Reply #32 on: 28 June 2015, 19:36 »
The main source of nice warm moist (ready to condense) air in to a car on a winter morning is the driver entering the vehicle! Small wonder the ice cold glass surface a few feet from his/her face mists up.....