Hi Mark, Couple of things have transpired since the issue. I had a family friend who retired working for Johnson Controls. He came out and said that the only thing that could be wrong is the motherboard on the contoller unit went out. the cost of the controller unit for my HVAC was approximately $2000, and a new Unit was $4500. I had an older unit, so i replaced the entire set up. I dont blame Google/Nest for "everything". It was a 19 year old unit, but it was working fine. I would caution Google/Nest to put a warning not to install on HVAC systems older than x amount of years. Also do not install on any unit that does not have a Common Wire. I learned the hard way.
Out of an abundance of caution after this issue: I returned the Nest Thermometer to Lowe's for a full refund and chose another brand.
to answer your other Questions: Other steps, over and above calling a retired technician. I tried to reset the Nest, removed it, placed it back on. Then i returned the unit to Lowe's. I think i got a message that there was a general wiring failure that power was lost to the Unit. I installed it Saturday the 3rd of February. I am in Tennessee, United States.
