disclaimer, this is my first attempt at doing any type of electrical work, so apologies in advance for any wrong terminology :)
I attempted to install a new Honeywell programmable thermostat. When I was in the process of taking down the old one (Lux), I noticed that there was no C wire, but that there was an extra blue wire coiled around the other wires, see below:
Per the Honeywell instructions, I found that you could use the extra wire in place of a C wire, so I continued on. But then, I got to the part where I needed to switch out the wires on my HVAC unit in the basement. When I got everything apart and took a look, I was a little confused by what I saw:
Does anyone know what that wire going into the C port is? It is definitely thicker than any of the other wires, and doesn't appear to be the same red wire in the RH port that was found on the thermostat. It does look that there is that extra blue wire coiled around the other ones, but am I able to plug that into the C port upstairs at the thermostat, and also into the C port at the HVAC unit (with the existing red wire)? Or do I need to run a whole new wire?
The furnace is a Ducane CG92TB067D12BA