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Chris 17
Jun 11, 2007, 02:10 PM
I am putting in a new furnace and thermostat. The connections on the furnace are C G R W1 W2. The connections for the thermostat are B O Y G W RC RH. There is a jumper wire on RC and RH. The thermostat instructions say to run the hot wire to RH and the neutral wires to W and G. I am using 3 wire and the colors are green, red and black. How do I properly wire the set up.

hvacservicetech_07
Jun 11, 2007, 02:13 PM
Is your new system heat only?

hvacservicetech_07
Jun 11, 2007, 02:15 PM
If it is just a furnace, you need to hook red to Rh either green or black to W on the thermostat, hook the same colors at the furnace, make sure you install a jumper between W1 and W2 at the furnace.

Chris 17
Jun 11, 2007, 02:29 PM
Red to RH on the thermostat and to where on furnace? Black to W on thermostat and where on furnace?

hvacservicetech_07
Jun 11, 2007, 02:32 PM
Red to R on the furnace and Black to W on the furnace, also install a jumper wire between W1 and W2 on the furnace. Make sense?

hvacservicetech_07
Jun 11, 2007, 02:34 PM
Also if you want to be able to run the fan manually, hook the green wire to "G" on the thermostat and "G" on the furnace

Chris 17
Jun 11, 2007, 02:36 PM
Ya that makes sense. If I hook the green wire to the G on both units , will I be able too opperate the fan from thermostat?

Chris 17
Jun 11, 2007, 02:38 PM
Thanks I am a little slow on the key board

hvacservicetech_07
Jun 11, 2007, 02:39 PM
No problem, post back and let me know if it works.This is an electric furnace I assume?

Chris 17
Jun 11, 2007, 02:40 PM
You bet.

hvacservicetech_07
Jun 11, 2007, 02:45 PM
If you don't mind, rate my answer if I helped you.

Chris 17
Jun 11, 2007, 03:36 PM
When I turn on the power the heat turns on , even with the temp set below room temp and the thermostat in the off position.

hvacservicetech_07
Jun 11, 2007, 07:14 PM
Sounds like you may have something crossed, What is wired where?

Chris 17
Jun 12, 2007, 02:25 PM
I have red to RH which has a jumper to RC,black to W and green to G on thermostat.I have red to R,black to W1 which has a jumper to W2 and green to G on furnace.

hvacservicetech_07
Jun 12, 2007, 03:00 PM
Remove all of the wires off the terminals on the furnace, turn the furnace on, Does it still come on?

Chris 17
Jun 12, 2007, 05:28 PM
No it does not turn on.I'll explain a little more.I had someone who helped me install the furnace and wire it by trial and erro.It seemed to run fine,started in low and then jumped up to high, turned on & off when supposed to.He had the red to W on thermo & W2 on furnace and black on RH & W1.I wanted to be able to operate fan from thermo so I hooked up green wire to G on both.Nothing happened.

hvacservicetech_07
Jun 12, 2007, 07:54 PM
Is this a 2 stage furnace? If so you are going to need a multi stage thermostat, but the way I told you to wire it with the jumper between W1 and W2 should turn it on and off. I really don't see how it would have ever ran with the way you are saying your friend had it wired. All you need is a wire suppling power from the "R" terminal on the furnace to "RH" on the thermostat, then you need a wire from "W1 and W2" to "W" on the thermostat and green to "G" on the thermostat and furnace.

Chris 17
Jun 12, 2007, 08:51 PM
This is a single phase furnace. If I disconnect the jumper between W1 & W2 the fan switch operates the fan fine.When I turn the thermo temp above room temp the fan turns on immediately on high.If I disconnect the green wire the furnace starts in low then up to medium with a pause at beginning,when thermo is turned up.