Nest compatibility

[Hangovers]

Hi Team, 

I know there is a great tool for compatibility, but it didn't help me anyway. All I know is that I have an AC unit, which can also heat. I would like to replace current thermostat with Nest thermostat. 

For some reasons I cannot upload a photo, which is in this case quite important. So I'll try to describe it as good as I can. For context, I live now in Spain, so we unfortunately don't have any labels associated to the cables. There are 4 cables connected to the current thermostat. Red/Orange/Brown and Black. 

I'll try to upload the picture in the comment section. 

[Hangovers]

Well, still cannot upload any images, that is kinda frustrating honestly. 🙂 

[Hangovers]

Okay, here is the image. 

[Hangovers]

Now I see, the EU version is "heating only", in that case it's quite useless for me. Please correct me, if I'm wrong, if not just ignore.