Nest 3rd Gen thermostat

[ritu1]

My old thermostat had a black wire and red wire - which of these wires go in which slot on  nest thermostat?

[AxelD]

Hi ritu1,

Thanks for posting in the community! For sure, I can help you to determine the compatibility with the Nest Thermostat. I'd like to ask you a few questions about it:

1. Do you have a Conventional HVAC system or Heat Pump?
2. What is the make and model of your HVAC system?
3. Have you used the online compatibility widget before you purchased the device?
4. Where are you located?

Keep me posted.

Regards,

Axel.