I use a 2nd generation Nest software 5.9.4-5 that in the past several months has been consistently over reading ambient room temp by 15-20 degrees F. it seems like a shifted baseline. For example this morning an independent thermometer read room temperature as 60 degrees while the Nest was showing 76. Then I forced Nest to start the furnace by changing the heat setting to 80 and let the furnace run until the independent thermometer read 65 degrees, a 5 degree change. The Nest at that point was showing 80 degrees, also a 5 degree increment and still the 15 degree differential. I understand there is no user calibration for the Nest. The Nest is on the same wall where it was originally installed, interior wall, no sun no nearby furnace vents no bright direct light and the wass is not warm to the touch. Also when I place the independent thermometer against the wall immediately adjacent to the Nest the 15 degree differential persists. What gives Nest? Can I trust that a new one will not do the same thing?
