Turns on the electric backup heat to soon causing sky high electric bills. My electric heating bill went up by 30% after switching to a nest thermostat. I installed a 16seer heat pump and started saving about $20 a month on average, more in the winter. When the nest 2 came out I thought I could save more but my electric bill has gone up over $30 a month on average because it won't wait for the heat pump to heat the house and starts the 10000 watt electric backup when there is more than by 1⁰ dif