Looking for advice/how-to take an existing thermostat that is wired to AC unit and use Arduino to make that a wireless connection.
Simple Example: One Arduino would have 8 wires coming out of it and going to the AC unit and another Arduino would have 8 wires coming out of it and going into the thermostat.
What I want to do summary: Use the existing thermostat wires that are ran to power both Arduinos and thermostat(1 on the AC unit and the other on the Thermostat). All other wires(2 Stage Heating & Cooling, Dehumid, etc) that can be used want to use Arduino to send those wireless between AC unit and Thermostat.
Problem I am trying to solve: Existing Thermostat wire that is ran is only a 5 wire run. I am needing an 8 wire run including Common/Power. Instead of running new wire, want to use existing wires to send power to Arduinos and thermostat so I don't have to use batteries. Then use Arduinos to send wireless communication for the other wires I need.
I am hoping I explained what I am trying to do in a nutshell above. Have a little programming experience and know how to wire the AC unit.
Any help would be greatly appreciated!!