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  • Dec 15, 2009, 05:31 PM
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    How do I hook up a programmable thermostat?

    I am attempting to install a programmable thermostat. My existing thermostat is a little dated (its one of the old mercury based ones) and the manual for the new one isn't much help. What I can tell is that it seems to be 4 wire, but the wires are blue, yellow, beige and white. They are currently hooked up where the blue, yellow and beige are hooked up to the mercury (from top to bottom, in that order) and the white one appears to be some kind of jumper. The yellow wire is connected at the other end to a dial that would indicate what the temp is.

    My existing HVAC system is a hydro-heat based system with an AC unit, so a 4 wire hookup makes sense. I'm just having trouble translating these colors into what the manual says they should be. The new one is a Rite Temp model 6025.

    I have attached a photo of what I am looking at.

    Any help would be greatly appreciated. Thank you very much!
  • Dec 15, 2009, 06:20 PM
    1 Attachment(s)
    You're doin' fine so far, but you haven't gotten to the actual control wiring yet. Loosen the screws at the corners and lift the thermostat off the switch base. There you go.
  • Dec 15, 2009, 06:36 PM

    Kc hit it. You are looking at the front of the stat, which is wired from the factory. You need to remove the stat and look to see what color wires you have on the back side of the stat. please let us know what you see.
  • Dec 16, 2009, 11:22 AM
    1 Attachment(s)

    I didn't quite realize that I wasn't quite far enough. After removing the base, I am looking at the following picture.

    I assume green goes to green; white goes to white, yellow goes to yellow. Where is get thrown off is that there are two reds, an RH and an RC. RH looks to be connected from RC and RC is connected from the wall. Also, there looks to be two yellows, one from the wall and one to the controls. This is making more sense to me than it did last night, but I still require a little help getting through this. Thank you so much for your help.
  • Dec 16, 2009, 05:00 PM

    Once you disconnect the wires, you will find that there are 4 or more coming out of the wall, the others are just part of the old thermostat. If the new t-stat has separate "Rc" & "Rh" terminals, be sure to put the jumper in. If additional conductors are present within the wall, one could be used to connect the "C" circuit between the furnace & t-stat, if necessary.
  • Dec 16, 2009, 05:01 PM

    One more step. Take the stat off the wall. Im sure you will find only the four wires, red white green and yellow coming out of the wall. The other yellow is most likely just hooked to the back of the stat from the factory.
    Now tell us what letters you have on the new stat. Should be as simple as hooking r or rh to red, w to white, g to green and y to yellow. There is most likely a jumper between rc and rh on the new stat, just leave it in
  • Dec 16, 2009, 08:29 PM
    The two of you guys are saving me big time. Thank you so much. I took the stat off the wall and there are just red, white, green and yellow. There might have been a blue in there, but if there was, there wasn't enough lead to be able to do anything with.

    The new stat is a universal type, Rite Temp 6025. It has terminals for 'C', 'B', 'O', 'W2', 'W', 'Y', 'Y2', 'RH', 'RC', 'G', 'A'.

    I assume at this points its Y = Yellow, W = White, G = Green, R = RC. There is currently no jumper wire between RC and RH on the new stat, but there are also 6 little jumpers off to the side of the new stat, should one of those act as the jumper between RH and RC? The terminals (easy connect type?) on the new stat are pretty thin, I'd be shocked to be able to fit both wires into it.
  • Dec 16, 2009, 08:32 PM
    1 Attachment(s)
    I meant to attach a photo of the new stat. Here it is:

    Thank you!
  • Dec 16, 2009, 08:56 PM

    Rc gets Jumped to Rh

    For the new stat, you don't have to wind the wire around the screw.

    Just strip a short STRAIGHT length, the length of the square washer. Just insert the straight length under the washer and tighten. You can use either side.

    Note, the jumper will be easy too. You'll have a wire on one side and the jumper on the other (for one screw). And a length for the other terminal.
  • Dec 17, 2009, 04:10 AM

    Originally Posted by bp84 View Post
    there are also 6 little jumpers off to the side of the new stat, should one of those act as the jumper between RH and RC?

    These are setup jumpers. There should be shorting clips in the package. The instructions should describe how to configure them for your system.

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