Thermostat compatability

[Khreshi]

I have these wiring on my existing thermostat. Is the nest compatible and if so what do I do with the connection that has 1 number and leg connection back to Y?

[zoeuvre]

Hi Khreshi, 

Thanks for posting here in the Community forum and for showing interest in our Nest Thermostats. Are you located in North America or Europe? What is the make and model of your HVAC system? And could you send us a photo of your current thermostat wiring configuration so we can take a closer look? You may check on our Compatibility Checker to determine if a Nest Thermostat is compatible with your heating and cooling system.
 

I'll look forward to your response. 

Best,

Zoe