I was looking around at my furnace wiring to see if my C-wire was connected on the furnace side and noticed that the C-wire from the thermostat goes to the R-terminal on the furnace. This doesn't seem correct to me, but are there any issues with such a configuration?
Currently the C-terminal on the furnace is connected to A/C and a humidistat, so there are currently 2 wires going to the C-terminal.
So if the current configuration is ok, then just wanting to double check. If the current configuration is not correct, what are the possible issues of this setup? Is the thermostat only receiving power when the heat is on? (the thermostat also uses batteries)
Is it safe to re-wire the black C-wire from R-terminal to the C-terminal instead? That would then make 3 wires attached to the C-terminal. At that point, should I pigtail them all together so that only one wire goes to the terminal?
Overall, I'm wondering why the furnace is wired the way it is.