incorrect temperature reading on Gen 3

[Jarpino]

My Nest Gen 3 thermostat has begun to display the incorrect temperature. This becan after an electrician switch the common (C ) to the Fan (G)  terminal and then back to the (C) after trying the fan only option.

I have restarted & factory reset the device but the problem is persisting. You can see in the photo that actual indoor temp is 69 while the nest reads 63.

Any suggestion are welcome.

[laurentbourg]

It can take time for the temperature sensor to adjust to the room in some situations, for example if you moved it to another room and moved it back. Also I assume you have the sunblock setting enabled?

[Jarpino]

Thanks for the reply.

Yes, sunblock is enabled. That said it has been in this location for a couple of years with no issue until now.

[laurentbourg]

This seems to be a hardware issue, you could try to lobby a replacement to Google support or alternatively buy a cheap Nest temperature sensor on Ebay. 

[JG5]

My thermostat is consistently off by 2 degrees. I have a home weather station that also provides the temp inside. It sits right next to my Nest so I can see the temp variation.  It seems as if restarting the thermostat temporarily solves the problem but it returns after a while. Is there a fix for this? I really like the product but it is giving my doubts and I am seriously considering going back to my original T6 thermostat.