Two-Wire Thermostat Configuration with Red & Black wires

[HiOctane]

I have a two-wire configuration with a Red Wire = V+ and a Black Wire = Vg.

I have a Gen 3 Learning Thermostat and all indicators, videos and specs said this was Compatible with 2-Wire Configurations. The two wire installation instructions are looking for a Red (RH) and a White (W1) wire connection. 

Please help! It's too late to return the Thermostat, and I checked compatibility before we purchased! Thanks. 

@Patrick_Caezza 

[AxelD]

Hi HiOctane,

Thanks for posting in the Community! Sorry to hear that your Nest Thermostat isn’t working with your system. No worries, help is here! To assist you better please provide me with the following information:

1. Does the thermostat screen indicate that it’s actively calling for heating?
2. Is it actually heating?
3. What type of furnace do you have? (gas, electric, etc.)
4. Is the display showing an error code?

Keep me posted.

Regards,

Axel.