Yesterday, an electrical contractor provided by Duke Energy replaced my outdoor electrical panel. It was a part of one of their programs to replace the older panels in our neighborhood. Before they started working - everything in the house (ac and heat included) - worked. No issues, no problems, ever.
I came home after they finished and noticed my thermostat said, "Systems detected." It displayed an image of the wiring behind the thermostat (Y1 cool, G fan, Rc power, W1 heat). I clicked continue, and it gave me an error message "E23. Wiring Report. No power to Rc wire detected. Learn more at nest.com/e23," and then I could scroll to a few other options.
Here's the summary from the "Equipment" option -
Equipment sensed on. No HVAC Connected. Wires inserted W1 - Y1 - Rc - G.
Here's the display summary -
Battery = 3.795 V. Voc = 0.02 V. Vin = 0.02 V. lin = 8 mA (o).
Here is what I've confirmed so far -
The breakers in the main panel are on and have not tripped. I've reset them multiple times and have confirmed that 240v is leaving the panel headed to the HVAC system. There are no other circuit breakers involved. I am receiving power at my HVAC unit (outside cool/heat unit). The circuit board fuse has not blown - it's good.
I am not receiving any power at the red thermostat wire inside the unit's control box. This unit is entirely outside, so there is no drain pan or float switch (at least none I know of).
Any suggestions of what to try trouble-shooting first? I know Duke Energy will say, "sorry, can't help."
