Hi paulvolz,
Thanks for reaching out to our community.
I appreciate you letting us know that you have a Honeywell thermostat that you’re replacing with a Nest thermostat. I understand that you need to know how to connect the black wire, since you have identified the wires connected in this order: Y, which is yellow; C, which is blue; G, which is green; R, which is red; and the black one is connected to the W. No worries, help is here.
Usually, the Nest thermostat is installed in the same way that the prior thermostat was installed, but if you have made any additional changes to the installation, I would require the following information:
- Could you please let me know the model of your Nest thermostat?
- Could you please take a picture of the Honeywell thermostat wires before you remove it from the wall and post it here?
- What is the model of your HVAC system?
If it is possible, I will also appreciate you posting a picture of the wires that are in the control board.
Thanks for your kind attention; I will be looking forward to your answer.
Best regards,
Virna
