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Can you change the fan speed switch to a dial switch?

Discussion in 'Electrical & Audio' started by AuroraGirl, Oct 3, 2019.

  1. AuroraGirl

    AuroraGirl Full Access Member

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    I have a 1980 no AC. It has the factory 4 or 5 settings in a rectangle switch, meant to go on the original unit. My lines that control the blend doors are rusted in defrost mode and it broke my sliding unit. So I want to put a piece of PVC plastic and drill 2 holes in it. 1 for an on-off switch for the heat (its stuck on) and one for the fan control. Its a lot easier to drill a circle and use a switch from a store than to try to fit the factory fan speed switch in. Can I use one of those dial switched(much like the dimmer for the headlights) to control the fan speed? Because an on-off switch I already have, but keeping the fan speed control where I want it will be difficult.
     
  2. 75gmck25

    75gmck25 Full Access Member

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    The fan speeds are controlled by a resistor pack mounted in the plenum under the hood (or maybe inside the truck if if does not have A/C), and the fan switch connects various combinations of resistors to get the speeds. It does not use a simpler rheostat (or dimmer) switch.

    If you are good at reading wiring diagrams you could probably just figure out how to mount multiple toggle switches to switch between resistors and control fan speeds. It wouldn't be elegant, but it sounds like you already have some major issues with the controls.

    Bruce
     
  3. yevgenievich

    yevgenievich Full Access Member

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    Actual 5 position dial switch rated for the current should be same as a factory switch
     
    Last edited: Oct 3, 2019
  4. RetroC10Sport

    RetroC10Sport Super Moderator Staff Member

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    I was going to attempt to adapt a digital climate control unit from a Buick Roadmaster, they are very similar in size. That's a LOT of work though.
     
  5. AuroraGirl

    AuroraGirl Full Access Member

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    What do you mean? Do you have a link for this?
     
  6. Dmack

    Dmack Full Access Member

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    Mine has a stripped out A.C. factory system. I just pulled a factory non- AC control panel, cables, and inside plenum as a full unit. Actually easy to swap out . And you can use all of the original wiring.
     
  7. yevgenievich

    yevgenievich Full Access Member

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  8. AuroraGirl

    AuroraGirl Full Access Member

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    Well I just figured a simple on-off switch would work. What I think im gonna do is figure out a way to keep the original fan switch and mount it in the panel. Ill find a way ahha. Thanks for the info so I didnt break anything
     
  9. AuroraGirl

    AuroraGirl Full Access Member

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    So it turns out I have a 3 speed fan. 1 up, 1 center, 1 down. Is there a switch that could do that?
     
  10. TubeTruck

    TubeTruck Full Access Member

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    a 3 position switch will be ON-OFF-ON, so you could use 2 speeds, high and low with center off. Don't think they make switches that will be ON in all 3 positions, at least I haven't seen them.
     
  11. yevgenievich

    yevgenievich Full Access Member

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