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Chevyman2006's avatar
Chevyman2006
Explorer
May 20, 2017

Need help wiring Honeywell thermostat

I removed the old Dometic thermostat last night to install a Honeywell thermo and can't get it to work. Of course, I didn't pay attention to where the 3 wires went on the Dometic and can't get that one to work either.

I've attached the pictures of the old and new thermostat as well as the wires coming out of the wall.

PLEASE HELP...it's 86 degrees in GA!
Wires

New Thermostat

Back of new

Old Dometic

Old thermo terminals
  • 2oldman's avatar
    2oldman
    Explorer II
    May 20, 2017
    Other than following the wire color scheme, or looking at manuals, I wouldn't know what to do.

    Dang.. how many times do we tell you guys to take pictures before doing this stuff!! :)
  • lj2654's avatar
    lj2654
    Explorer
    May 20, 2017
    on your old thermostat same as mine:

    black wire goes to 12v-

    orange to comm

    red to 12v+



    I am not sure how to wire the Honeywell thermostat
  • time2roll's avatar
    time2roll
    Nomad
    May 20, 2017
    Honeywell will not work with the digital control board up in the ceiling.
    Above colors sound correct.

    It looks like the prior owner upgraded your thermostat. The twisted/curled ends are probably not used anymore. The three wires with straight ends that are trimmed are probably what you removed from your single zone.

    There is an updated single zone now available. Called Comfort Touch.
    Still not programmable.

    http://www.adventurerv.net/dometic-single-zone-lcd-control-thermostat-3313192000-p-29797.html
  • Chevyman2006's avatar
    Chevyman2006
    Explorer
    May 20, 2017
    lj2654 wrote:
    on your old thermostat same as mine:

    black wire goes to 12v-

    orange to comm

    red to 12v+



    I am not sure how to wire the Honeywell thermostat


    This isn't working


    Is there something else I can check? Yesterday I could get the screen to work on the old Dometic...but now nothing.
  • time2roll's avatar
    time2roll
    Nomad
    May 20, 2017
    Do you have a voltmeter? Check that you have 12v red to black.

    If you have voltage you can open up the interior ceiling access to verify the Orange wire is connected or some other color.
  • sayoung's avatar
    sayoung
    Explorer
    May 20, 2017
    If that Honeywell is a standard residential thermostat I don't think it will work with only 12voolts as we use 24 volts on residential equipment. It might work with the batteries installed.
  • Chevyman2006's avatar
    Chevyman2006
    Explorer
    May 20, 2017
    time2roll wrote:
    Do you have a voltmeter? Check that you have 12v red to black.

    If you have voltage you can open up the interior ceiling access to verify the Orange wire is connected or some other color.


    I do have one, but I'm an idiot on working one.

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