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Headlight Dehumidifier

  1. Feb 20, 2009 #1
    Ok, we have all seen it.... a build up of condensation inside a car's headlight. I have been looking around and there is not a dehumidifier built specifically to remove this nuisance. I am in the business of restoring automobiles for car dealerships and i think that this would be a great add on business. I, however, lack the brain power to develope such a machine so i am looking for a few braniacs to help aid in this invention.

    Step one:

    Turn the water in the headlight in to water vapor.

    I have found that this is easily done by removing the bulb from the back of the assembly and simply placing a hair dryer on the back where a hole is left from the vacated bulb.

    Step 2:

    This is where i start running into problems.

    I would think that you would simply need to remove the air from the headlight to complete this process. Would you even need to build some sort of machine that removes the humidity
    or would you simply need to remove the air? Removing the air would be as simply as rigging a squirel cage fan on the back of the headlight assembly ipsofacto removing the air (water vapor from the headlight assembly. Would you even need to build a contraption that could be more efficient or would pumping the air out do nothing at all? I need a couple of you braniacs on this to help me figure this problem out.
  2. jcsd
  3. Feb 20, 2009 #2


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    Gold Member

    Welcome to PF, Carsmeticsga.
    If the housing is truly sealed, humidity shouldn't be a problem. Our temperatures range from -50 C to +35 C, and the only times that I've seen fogging is when there was a hole or crack in the plastic. I'd consider just introducing a dessicant such as the silica gel found in pill bottles, then sealing the unit with something like silicone.
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