Hi Figo,
Thanks for posting in the Google Nest Community forum. I'm sorry for the delay. It looks like you have a conventional system. Your system is compatible with the Nest Thermostats such as Nest Learning Thermostat and Nest Thermostat E. However, if you prefer to have a Nest Thermostat 2020, you might be needing to install an additional wire for common (C) or a Nest Power Connector.
You can follow the wiring guide below:
For Nest Learning Thermostat:
- Y1 - Blue (Cooling)
- W1 - White (Heating)
- G - Green (Fan)
- RC/RH - Red (Power)
For Nest Thermostat E:
- Y1 - Blue (Cooling)
- W1 - White (Heating)
- G - Green (Fan)
- R - Red (Power)
For Nest Thermostat 2020:
- Y - Blue (Cooling)
- W - White (Heating)
- G - Green (Fan)
- R - Red (Power)
Note: Nest Thermostats don't use jumper wires. Therefore, don't use the orange wire connected to the R and RH terminal.
Best,
Jenelyn
