2 Wire Thermostat

[Mark236]

I am having trouble trying to match the appropriate wires to the nest thermostat. I have a heat pump and A/C operated by my thermostat. But only 2 wires coming out of the wall. One is red labeled V+ and the other is white labeled Vg. 

[Patrick_Caezza · Accepted solution]

@Mark236 

It sounds like your thermostat isn't compatible with any of the Nest thermostats.

[HiOctane]

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