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Building a 12v heater for my car

  1. Dec 23, 2011 #1
    I am trying to upgrade my antique car while still keeping the factory look

    The rear defroster is a blower motor that sucks in cabin air and blows it onto the back window. The air in the cabin has to get warm before the windows will defog.

    I am thinking of helping that a little by installing a 1 to 2ohm resistor rated at 200 watts. It will run around 7 amps and will use 12 gauge wire. The blower will blow air over the resistor and heat the air.

    Will this work?.....the only thing i don't like is how big the resistor is.....its 7x3 inches

    i really would like something to do the same job at 4x1 inches as space is limited or really as small as i can get and still have some good heat......im replacing the hose that goes from that blower motor to the duct work with metal pipe....so all of it needs to fit into that space

    is there any other more compact way to do this that i haven't thought of?

    i did find something like this
    http://sunelectricheater.com/ that was 1/8 inch wire that got red hot to 1400°F need something like that that gets to 150°F

    Attached Files:

  2. jcsd
  3. Dec 23, 2011 #2

    jim hardy

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    Science Advisor
    Gold Member

    you might try a little Halogen 12V 100 watt lamp, or a couple 50's. they're easily replaced and you can get sockets for them... look in lighting dept at hardware or auto parts store... they sell them for closets and off-road lights.

    but put in some precaution against fire if your air intake gets blocked. fusible link?
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