I have just installed EcoBee tstats on two identical systems. They are both Carrier 58MVP, 2 stage heat/cool. I started with one system, and noticed that the stat would reset itself randomly. I called my supplier and received little help, as the tech guy was slightly arrogant and didn;t know what he was talking about. I then decided to call Ecobee, received some direction from them, but am still having issues. They felt that I am having power issues which is causing the stat to reset. I have seen the stat reset even while the heat is running, and the heat continues to run. I ruled out wiring and all hardware by swapping parts and setting up test rigs. At this point, I am out of ideas. The last thing that I did was to feed the Ecobee control unit with its own dedicated 50 va transformer. I am still tapping off of the 120 circuit to the furnace. I do not know where else to look. If anyone is familiar with these units or have any ideas, I am open to suggestions. I bought three of these and have literally spent the better part of 2 days trying to get them to work right. I installed the second setup just to see what would happen and of course, I am having the same exact issue with the second setup too. So, I am convinced that this is not the Ecobee equipment, but something with either my power or noise??? Any ideas?