Hi guys I bought a new touch screen thermostat and after installing it, it's not powering up. I have a wire going to c in furnace electrical panel but does not come up to the thermostat. The thermostat I have is a honeywell rth9580. I have r going to r w (white) going to w y (black) going to y. And g going to c. Any help is well appreciated.
You can sacrifice the fan control and use G, but you have to remove it from the G terminal in the furnace and connect it to C. It sounds like you are connected from the furnace G to the thermostat C.
Buy the Honeywell THP9045 Wiring Module in order to keep the G fan control,
http://www.pexuniverse.com/docs/pdf/hw-69-2065-installation.pdf
Hi thanks for the reply. Is there anything else I can do at the thermostat instead of changing wires at the furnace control? As I have a wire coming from g and c it's confusing as to why the c wire did not make it up to the thermostat.
do you have 5 wires at the furnace and only 4 wires at the thermostat? you need 5 wires at the thermostat to the furnace to make it work. otherwise like admin said you need the add-a-wire kit.
If what you're saying is that you see one single wire coming from C, then odds are this wire is not going to your thermostat. Your Air Conditioner also has a wire going from Y and C to the contactor on your outside unit. So if you have an air conditioner right now and see only one wire at your C terminal, then you do not have a C wire going to your thermostat. Logic dictates, that if you have a C wire going to your thermostat and have an air conditioner at the time, you should have 'at least' two wires to your C terminal. Three, if you also have a humidifier.
Hey really appreciate the clarification, as this is new to me but have already started running new c wire. Thanks guys!