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What is the 5th wire on the old thermostat?
That does not sound right. Do you have the brand & model number of the old thermostat?
Sure it is not a "C"?
Ok, thanks....standby while I look it up.
Ok, the red wire labeled 4 is actually RH. You have a 2 transformer system, so on the new thermostat, remove the jumper between RC and RH. Then connect the red wire on terminal 4 from the old thermostat to RH on the new thermostat. Make sure you remove the jumper though between RC and RH.
Does your new thermostat have RC and RH with a jumper between them, or just R? I was just assuming it does.
Ok, you will need a different thermostat then that has RC, RH, G, Y, and W. Any more questions? My goal is to provide you with excellent service - if you feel you have received anything less, please reply back as I am happy to address follow - up questions. Kindly rate me when you are done.
Yea, the new thermostat will not work for your application. The H terminals are for a humidifier. RH is for the furnace and RC is for the air conditioner. If you do that then your A/C won't kick on.
Any other questions?
No problem. Have a good day!
http://www.upm-marketing.com/tutorial/301/index.html This is the link to the tutorial to replace your thermostat, which states if your original thermostat has 5 or more wires you will need a different model of their thermostat.