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Electric Baseboard thermostat wiring

I am replacing the thermostat for my 2 electric baseboard heaters and the replacement unit I bought has 4 wires, red, white, green and black while the old uint had just red and black.

There are 3 white wires, 3 black wires and bare solid copper. I know the green wire connects to bare copper, but I am confused on how to connect the others.

How should I connect the wires?

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  • 3 more comments 
  • jsylvia Jan 27, 2008

    It is not a thermostat, it is an electronic countdown timer made by Intermatic model E12I0WC.

    The heater is 240 volts

  • jsylvia Feb 04, 2008

    I returned the timer unit since it still required a working thermostat to control before it would work. I am back to installing just a thermostat. There are 2 red wires and 2 black wires and a ground point on the unit. I don't have the brand or model number with me and I am away from home this week. However, can handle up to 16 amps and 240v. It is controlling two base board heaters. There are 6 wires come out of wall. 3 white and 3 black. what do I connect the red ones to, and what do I connect the black ones to?

  • Anonymous Feb 27, 2008

    I have to replace a two wired thermostat with a new four wire marley model m602. there is only two wires hooked to the old thermostat. where do i hook the two red and two blacks wires to. i did this in the bedroom and hooked both black wires to the wires and didn't hook the red wires to anything. will this work.

  • Anonymous Mar 09, 2008

    Top two wires are hooked up to the hot and the bottom two are hooked up to the heater and the end baseboard wires are hooked up to a second baseboard heater. Has two black wires at opposite ends that are connected to the second base board heater, red on black and black on black. The second heater on opposite end with the two black wires are connected by a wire nut, do you have to seperate these wires?

    Two red and black wires are preconnected, red on black with a crimped wire nut and a removable wire nut on red and black. the other end has two black wires with removable wire nut.

    I have a dual 15amp breaker with **.10/2 wire for 240 volts.

    The connection is black on black in the thermostat and red on white.

    the thermostat bottom wires are connected to the baseboard, red on red and black on black.

  • ellababies Nov 24, 2008

    I just purchased a Honeywell 5-2 Day Programmable Thermostat for Electric Baseboard Heat. The problem is my electrical box in the wall has 4 wires (i.e. two black wires and two white wires) or 2 wires each for 2 separate baseboard heaters and an add'l ground copper wire (1 unit in the living room and 1 unit in the bedroom) which were all connected to one manual thermostat that had 4 wires (2 blue and two black) and my new thermostat only has two black wires but the diagram that came with it says you can also connect the thermostat unit for a 4-wire installation, but the diagram is very confusing. The 4 wires in the wall are 2 sets of white/black, so it is confusing since we have tried different variations of connecting the 2 black wires from the new thermostat unit to the 4 wires in the electrical box on the wall (i.e...1 black wire w/2 white and 1 black wire w/two black, and 1 black wire w/1-black/1white x2 for each of the two units. None of these variations have worked, but it trips the main circuit breaker off when we turn the new thermostat unit on, so we figure we must be missing something in the connection that is causing this to happen. Any help would be appreciated. Thanks. from LG BMore



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What is the make of the thermostat? are the heaters 240 volts?

Posted on Jan 27, 2008

  • Anonymous Feb 02, 2008

    I went to the intermatic site and your number is not a good number.

  • Anonymous Feb 04, 2008

    attached is a diagram which can be opened in windows "paint"
    follow the diagram and you should be ok.



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