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Argh! Inside of the windshield is foggy

Discussion in 'Gen 2 Prius Main Forum' started by daveleeprius, Jan 4, 2007.

  1. daveleeprius

    daveleeprius Heh heh heh you think so?

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    This has to be my number one gripe about the Prius. Brand new car off the dealers lot, 28 miles on the odometer. Even on our test drive on a sunny afternoon we're hitting the defrost!

    Anyone have any good way to de-fog the inside of the window? Fog-X a good product?

    This is very annoying on an otherwise very pleasing car!

    Dave
     
  2. john1701a

    john1701a Prius Guru

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    Sounds like you have the RECIRCULATE on... which traps moisture inside. Turn it off.

    Allowing outside air to come in through the system helps to prevent fogging. Turning on the A/C really helps, since the condenser has a dehumidifying effect.
     
  3. priusenvy

    priusenvy Senior Member

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    Human respiration increases the relative humidity of the air inside your car.

    My suggestion for you to solve your windshield fogging problem is to stop breathing.
     
  4. daveleeprius

    daveleeprius Heh heh heh you think so?

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    <div class='quotetop'>QUOTE(john1701a @ Jan 4 2007, 06:27 PM) [snapback]371000[/snapback]</div>
    No recirc, but I don't want to use A/C as this will lower milage somewhat, right?

    Dave
     
  5. hyo silver

    hyo silver Awaaaaay

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    Using AC will lower your mileage, but it's a reasonable price to pay for being able to see where you're going. It's not a bad idea to use it once in awhile, anyway, just to keep it functioning well. Using the touch screen, you can also set the system to blow warm air on the windshield without using AC, and toggle the defrost button on the steering wheel as you need it.
     
  6. john1701a

    john1701a Prius Guru

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    <div class='quotetop'>QUOTE(DaveLeePrius @ Jan 4 2007, 05:58 PM) [snapback]371017[/snapback]</div>
    You have no choice. If the standard blower on the windshield isn't enough, pushing that defrost button (which triggers the A/C) is a must. The extremes of winter are like the extremes of summer... both cause lower MPG.

    Fortunately, the A/C is electric. So even using it is still more efficient than the traditional belt-driven type.
     
  7. donee

    donee New Member

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    Hi DaveLeePrius,

    The HVAC controls take some getting used to. Here is what I have learned in the recent really moist weather here.

    Go to the climate screen. Turn Auto off if its on, and make sure receirculate is off. Hit the vent control icon all the way to the right (the one with the window in the icon). Now hit the fan control icon two steps from the left. Above 35 F you wont need any heat, but it wont hurt either.

    You wont feel any breeze from the vent, unless you put your hand down there. This is how I became confused on this initially. I am used to feeling the breeze to know its working. But, the air will travel up along the inside of the front window, along the roof, then down the rear window, and out through the battery vents in the wheel wells of the car. Voil'a after a few minutes, no fog. And no need to run defrost or the heater.

    First thing in a below freezing morning, you will need to get the windows clear, like in any other car with the heated defrosting. Which takes the same time as in any other car I have had. But then switch to this mode, and the windows should stay clear.

    I figured this out when I saw a diagram of a computational fluid dynamics simulation in an advertisement for the Prius. I figured somebody must have figured this out (like most things on the Prius - most engineered car of its time) , I just gotta learn to use it.
     
  8. seasalsa

    seasalsa Active Member

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    <div class='quotetop'>QUOTE(DaveLeePrius @ Jan 4 2007, 03:58 PM) [snapback]371017[/snapback]</div>
    Dave,
    Take it from a fellow Washingtonian, use AUTO A/C and set it to the desired temp. This will keep the windows clear. A/C does not mean Air Conditioner, it just shows the the Climate Control System is operational. As you are only in the early stages of break-in with 28 miles you will not noticably affect mileage.
     
  9. member

    member New Member

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    <div class='quotetop'>QUOTE(DaveLeePrius @ Jan 4 2007, 04:17 PM) [snapback]370997[/snapback]</div>
    VOCs from new plastics will accumulate on glass (and everything else) and provide nucleation sites for rapid fogging. This is peculiar to brand new cars. You can reduce that by simply cleaning your glass frequently while the car is still outgassing VOCs.
     
  10. donee

    donee New Member

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    Hi All,

    DaveLeePrius, if you are having unclear windows. That is, they are kinda hazy even in warm weather. Then you need to clean off that new-plastic scum that gets on the window like Display Name said. I would be suprized its that bad at 28 miles. It will get worse as the plastics out-gas. Took my car about 4 months to get real scumy windows. What worked was to use a micro-fiber cloth with Stoner brand "Invisible Glass". Do not use anything with amonia in it (windex?). Just makes the scum more hazy. This was suggested in another thread in the "Care and Maintenance" section of Prius Chat originally (not by me).
     
  11. curtissac

    curtissac New Member

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    <div class='quotetop'>QUOTE(DaveLeePrius @ Jan 4 2007, 06:58 PM) [snapback]371017[/snapback]</div>
    I used my Auto A/C around the clock during the summer and got better mileage than I getting now. The effect of the air conditioner running is really negliable most of time. It dries the air and makes the defog more effective. As mentioned earlier - a small price to pay in order to be able to see.

    My Auto A/C is on most of the time now as well.