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Electric thermostat on 12 volt DC

Post in 'DIY and General non-hearth advice' started by Dune, Feb 4, 2011.

  1. Dune

    Dune Minister of Fire

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    Short story; I am using a car radiator and electric fan (12 volt) as an air handler. The heat becomes too much after a time. Can I somehow rig a thermostat to a soleniod to start and stop the fan? Any suggestions as to a particular solenoid? This is not in a building.

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  2. semipro

    semipro Minister of Fire

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  3. Dune

    Dune Minister of Fire

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    Room temp., say 55-70F.
  4. semipro

    semipro Minister of Fire

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  5. Dune

    Dune Minister of Fire

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    That looks good. Relay is what I meant by solenoid. Can you recomend one of those also?
  6. WhitePine

    WhitePine Feeling the Heat

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    If you are not using it in a building, where are you using it, and what do you want to measure the temperature of? Air, fluid, or something else?




    If it is air temperature, you probably can just use a cheap line voltage thermostat to switch the 12 vdc directly. No need for a solenoid or relay.


    Take a look at http://www.google.com/products/cata...og_result&ct=result&resnum=2&ved=0CH4Q8wIwAQ#



    These things are normally for switching the power to high current AC resistance heaters. It won't be rated for 12 volt operation, but I can't think of any reason it wouldn't work, unless you are using some sort of monster fan motor. It should be nothing more than a set of heavy duty adjustable temperature sensitive bi-metallic contacts.

    I had a house with a similar thermostat switching the fan motor on and off on a hot water radiator in a garage. Worked fine.
  7. semipro

    semipro Minister of Fire

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    Use one from an automotive application like one for fog lights. Auto supplies should have them. You just need to make sure the amperage rating of the contacts is more than your fan consumes.
  8. semipro

    semipro Minister of Fire

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    This is better yet. You can buy at the big box stores and 22 amps is probably enough to handle your fan. I thought of these but didn't know they went that low on temp.
  9. Dune

    Dune Minister of Fire

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    Awesome. It is a workboat. No problem regulating the heat during the day, but after you fall alseep it gets way too hot if you leave it on, and too cold if you leave it off. So that is a thermostat for electric baseboard?
  10. Dune

    Dune Minister of Fire

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    Thanks to both of you for the fast great help. What a place this is!
  11. WhitePine

    WhitePine Feeling the Heat

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    Yes, it is.

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