No COOL Mode

[CarlesEscude]

Hello everyone,

I'm new to this forum. I'm here because I have a question about my Nest Thermostats. I have a house with two zones controlled by two thermostats and a central aerothermia unit (Hitachi RAS-3WHVRP) that independently controls the radiant floors. They work correctly in heating mode.

The problem comes when I want to set them to cooling mode. This mode doesn’t appear on the thermostat—only HEAT and OFF. What could be the issue?

Many Thanks

[CoolingWizard · Accepted solution]

@CarlesEscude, if the nest does not see a wire attached to the Y, Y1 or Y2, It will not configure cooling. 
if you recall in the installation instructions, it suggested you take a picture of your old thermostat wiring, and if you have a moment do a favor and upload that picture of the old wiring and in include a picture of your current nest backplate showing the wires that are attached

AC COOLING WIZARD

[CarlesEscude]

Hello,

Thanks for your response.

And what if the thermostat isn't connected to the wires? It is on the mobile base.

Thanks

[CarlesEscude]

And another question: what needs the heat link work with cool mode?

[CoolingWizard]

Hello, I didn’t know that you were actually over in Europe. It looks like you’re at someplace in Europe and those are systems. I’m not really familiar with.

AC Cooling Wizard