3rd gen Nest Thermostat has been working fine for the last couple years. Now get message low battery, can't connect to WiFi. Charged on USB and device got very warm. Still shows low battery/can't connect when put back on base.
Had wiring, power checked by electrician. Moved the thermostat from upstairs to downstairs and still the same issue. Low battery, charged on USB, unit says to put back on base, unit gets hot from charging then when back on base thinks the room is HOT and turns on the AC. And still get the same low battery message.
Thanks for the response. Could you share how your Nest Thermostat is wired? Also, please check the power readings of your Nest Thermostat. You can find this information by going to Settings > Technical Info > Power.