Got me a wefe thermostat. Old thermostat used 4 wires but the blue C was stuffed in the wall. I have read many forums and nobodys setup really matches mine. enter image description here

This what I see at the furnace and what I think the functions are. I see the spot for C but it has a red and yellow wire connected to it. I figured T would be the common but when I hooked the blue wire to this I got power to my new thermostat and could make the fan come on but the A/C would not turn on. Guess my only question being is where to put the darn C wire. Any help would be greatly appreciated!

Here is the old tstat and setup in the furnace. I cannot see a model anywhere on it. Just says climatrol. It is an older one tho with a pilot I gotta light manually.

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Here is the wifi stat setup.enter image description here

I turned it back on and afew minutes later while uploading this pic it the system came on!!! Musta took 3 to 5 minutes but its working! Will make sure it does what it is suppose to do but thank you for advice on waiting and the other help you provided. I really appreciate it!!!

  • Can you post a picture of the actual wiring inside your furnace? What's the make/model of the furnace? Can you post a picture of the old t-stat? – Matt Jul 20 '19 at 16:36
  • There is the setup. Mess of wires inside the air handler but the picture i drew gives the layout and the letters on the board. Not sure why the Heat is white on the air handler and brown when it gets to the thermostat. – Eric Jul 20 '19 at 16:58
  • I think T might be common as well. You could test it with a volt meter to be sure (voltage between V and T should read 24 if V is indeed power - test between V and ground to make sure). How long did you wait for A/C to come on? Sometimes there's a significant delay from fan on to cooling. Can you post a picture of how you wired your WiFi stat? – Matt Jul 20 '19 at 17:25
  • There is 24 between V and ground as well as V and T. I waited about a minute or two. When i set the thermostat to cool and and fan to auto it clicked but nothing happened. When i set the fan to on the fan came on but not the outside unit. So i set the fan back to auto and after about a minute the fan shutoff. Will get a pic of how I wired the stat when my internet quits being dumb. I wired it the way it said to. In the manual. Only thing different from the old was the new blue common wire and i put that in thr C spot – Eric Jul 20 '19 at 17:43
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    Hello, and welcome to Home Improvement. It looks like you now have two separate accounts; you should request that they be merged. And, please take our tour so you'll know how best to contribute here. – Daniel Griscom Jul 20 '19 at 18:39

T is common, confirmed by reading 24VAC across T and V (24VAC should also exist across V and ground to confirm V as hot). A/C may need a few minutes to kick on.

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