Nest is blowing cold air when on heat

[Shearfaith206]

Hi! We have had the nest during the summer and it worked fine but now when I switched to heat, it will only blow cold air. I have read through and tried the advice given to others like switch the blue wire but it received no power when I did that. Help!

[luciaaa]

Hi, @Shearfaith206!

Thank you for posting in the community. I apologize that your thermostat is cooling instead of heating. I understand the importance of maintaining the correct temperature, especially as winter approaches. I’m happy to help!

To troubleshoot effectively, please provide the following information: 

• What type of thermostat do you have? 
• Is your HVAC system a conventional or a heat pump system? 
• Would you mind sharing a picture of your wiring configuration?
• When was the last maintenance check for your HVAC system?
• Have there been any recent changes or upgrades to your HVAC system?
• Does the issue happen with heating only, cooling only, or both?
• Are there any error messages?
• Is this the first time you're activating heating since the season changed?

In the meantime, ensure wires are fully inserted: The wires may not be making a proper connection with the terminals. Make sure at least ¼ to ½ inch of the copper wire is exposed, straightened, and fully inserted into each of the required connectors. If necessary, strip and reinsert the wires.

Please let me know how it goes.

Best regards,

Ana