No heat mode

[Eclipse_lite]

Hello everyone, 

I am having trouble setting up Nest Thermostats at my condo,

I had the following wires on my old thermostat:

G,O,Y,Rc,C

On the old thermostat there is a toggle between "heat" and "cool" modes, as well as 'auto" and "on"

When i installed nest and connected the wires as per Google Home app, I am only getting cool mode. The heat mode is not available in the menu on the thermostat, or the app.

How do I enable heat mode? Do I need to  hange any wiring?

Thanks

[Patrick_Caezza]

@Eclipse_lite 

Post a picture of the original thermostat's wiring here.