Sorry for the newbie question, but I would like to hook up a C wire so that I can get a Nest, Ecobee, etc. My current thermostat is just a regular battery operated Honeywell and looking at the current thermostat wire, I have the extra blue/brown wires available, but they aren't being used and not connected to anything. I looked at the control board at the handler and there already is a wire on the C terminal going to the air conditioner condenser outside.
In the picture below - the top red (R), white (W), green (G), yellow (Y) and the unconnected brown/blue wires are going back to the thermostat . The middle white (C) and red (YR) wires go to the condenser.
I assume I need to connect the blue wire from the thermostat to the C, but what do I do with the existing white wire that is already connected? Can both of the wires go on that terminal?
I also attached the wiring diagram for my air handler