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Windshield, driver's window interior fogging

Discussion in 'Model S' started by ualdriver, Feb 27, 2015.

  1. ualdriver

    ualdriver Member

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    It's cold up here in the Midwest, with temps getting close to 0F at night and the low teens during the day. I'm noticing that my driver's side interior window and the driver's side (only) windshield tend to fog up. I'm assuming it is doing that due to the driver's (me!) exhaled breath condensing on the very cold interior window surfaces closest to the driver.

    The problem is that I've never had a problem like this in any other car before. None of my Prius have this problem. My Volt didn't. Usually having the heater on sends warm air to the side windows, so those wouldn't fog. The windshield.......not sure why that's fogging. Yes, I realize that I can turn the windshield defogger on, but even then it takes quite a while to un-fog. Again, in my other cars just having the heater on seems to prevent all the windows from fogging up.

    I'm wondering if I have an airflow problem to the driver's side of my car? Hard to quantify, I guess, but even the little vent by the side window doesn't put out much air with everything in auto.

    Anyone else noticing this problem?
     
  2. markb1

    markb1 Active Member

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    Does your car have vents up by the windshield? If not, Telsa will retrofit vents for free upon request, and that should improve things. I think the newer cars should already have this, though.
     
  3. ualdriver

    ualdriver Member

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    I don't know. What do you mean by vents up by the windshield? I think there is a mesh(?) covering of some sort along the entire bottom of the windshield, but that's it. Do you happen to have a picture? My car was built in mid-2013 I think.
     
  4. markb1

    markb1 Active Member

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    There's a picture here:

    Side window defrosters | Forums | Tesla Motors

    The mesh does act as a vent, but the retrofit creates larger vent holes for more air flow. It sounds like you don't have the newer design. Your car is just a few months newer than mine, and mine does not have the vents, either.
     
  5. ualdriver

    ualdriver Member

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    Excellent. Thanks very much for that.
     
  6. scaesare

    scaesare Active Member

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    I believe that the vent pictured in that link above on;y comes standard with the cold weather package. For some time you could also request it as a retrofit to a standard car if you had window fogging issues, but I'm not sure if that's the case any longer.

    When I first got my car I had tendency to over-ride the HVAC controls and enable recirculating air in the winter, with the idea that it will take less energy to keep the interior air warm than to allow the car to draw in cold winter air and have to heat it up to cabin temp. As a result, I'd get window fogging pretty easily.

    I've since just left the HVAC controls on Auto and allowed the car to mix in fresh air as needed, and I don't really have an issue with it any more. If it uses more energy to do so, it's pretty negligible...
     
  7. stevezzzz

    stevezzzz R;SigS;P85D;SigX

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    The mesh-only windshield vents were a feature of the earlier cars. I had Tesla retrofit the newer vents on my Sig last winter, no charge, and the problem got lots better. Still not perfect when the weather turns really cold: but it's manageable with fan speed and/or the 'blue' defrost setting, as needed.

    The one downside is that the new vents reflect more glare off the windshield, but that is a minor nit compared to having condensation-free windows.
     
  8. mknox

    mknox Well-Known Member

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    I have found (at least on earlier versions of firmware) that Tesla runs Recirculate way too much in the cold. I over-ride that setting and manually select outside air all winter and haven't had the slightest hint of fogging, even without running the defrosters. Recirculate in the cold is a big no-no and a safety concern in my mind.
     
  9. ualdriver

    ualdriver Member

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    Yeah, I wondered about that. Also, I think in my Volt, the air conditioner was almost always "ON" with the cabin air conditioning system in AUTO, whether it was summer or winter. I assume that was to dehumidify the air. I'm not sure if the air conditioner runs ON or OFF in the Tesla while in AUTO during the winter.
     
  10. CHG-ON

    CHG-ON Still in love after all these miles

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    Get the new defroster vents. Should solve most of your problem, along with using fresh air rather than recirc. No cost for the retrofit. Also try preconditioning the car if you can through the mobile app.
     
  11. Vitaman

    Vitaman Member

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    Although not in the frigid Midwest, my windows fog up way more than any other car I've had.
    Since it's a D I assume it has all the vents it needs. I have to use the Defrost setting considerably more often than in previous cars.
    It works well in the front, less well on the rear window and barely at all on the side windows.
    At times it borders on a safety concern. Still not used to turning on climate control 5 minutes before driving. Have a feeling that would help.
     
  12. wycolo

    wycolo Active Member

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    If you exercise then jump in the car this will tend to happen regardless. An inexpensive portable fan/heater unit that plugs in the cig lighter socket can help keep the glass clear.

    Lacking the improved venting I usually alternate between fresh air and recirculate as needed, but this in a dry climate.
    --
     
  13. Zapped

    Zapped Model S - PURE EV

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    Personally I don't like the look of the vents and requested they not be installed. I was in a MS that had the vents and found them too visible and distracting.

    Luckily I have a heated garage but I also find that to keep the humidity down, I need to remove the melted snow from winter floor liner from time to time.
    Also need to manipulate the heater controls. Automatic does not always work.

    Even opening a rear window a crack will help a lot ( I'm no expert but I used to own an older VW beetle at one time )
     
  14. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    I like the clean look too, and the Model S doesn't hold a candle in terms of fogging compared to the Land-Rover Series III. If the wind was coming from the passenger's side, it would stop the fan.
     
  15. markb1

    markb1 Active Member

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    Since you have a new car, be sure to clean the interior of your windows often. Off-gassing from the new materials can coat the windows and make fogging worse. As the car ages and off-gassing decreases, you won't need to clean insides of the windows as often.
     
  16. mknox

    mknox Well-Known Member

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    I do as well, but there was no way I was going to survive the Canadian winters without the defroster retrofit and had it done on my car. There is a reflection at the bottom of the glass, but just like the 1" or so of glass distortion along the bottom, you get used to it. (BTW, do newer cars still have the distortion along the bottom? Haven't heard it discussed much lately).
     
  17. tezco

    tezco Sig P85

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    I had the retrofit done last year as well , and the fogging issues are much improved. Initially I didn't like the reflection of the new louvers on the lower windshield, but now I hardly notice it. For me, the optical distortion of the glass at the bottom of my windshield is more of a distraction.
     
  18. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    Totally agree. I don't have to deal with fogging for more than a few weeks a year, and not every day during those few weeks.

    I don't even notice the distortion on the bottom anymore, and I can't recall if it was present on the last loaner I had.
     

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