e24 error message

[wstew]

My Nest has worked fine for 5 years. Today I am getting an E24 error message that there is no power in the Rh wire. Power works everyplace else in the house. The Nest required recharging which I did using the USB port. I plugged it bak in and am getting the same error message. Do Nests go bad? Or do I need an electrician to tell me the Nest is bad?

[Markjosephp]

Hello wstew,

Thanks for reaching out to us! I'm sorry to hear about the issue you're facing with your Nest Thermostat. I understand that it works fine for five years and then suddenly encounters a power issue. The E24 report typically indicates a problem with the Rh (heating) wire, suggesting a power-related issue.

Let's consider a few troubleshooting steps:

• Ensure that the USB rechargeable battery is holding a charge, and try reseating the Rh wire securely.
• Gather the power-readouts in the Technical Info settings. This would help us identify a possible wiring issue.
• If your thermostat has a C-wire, remove it and leave it disconnected. Then, attempt to inspect the thermostat power.
• Check for any loose connections or corrosion on the thermostat wires. It's also a good idea to inspect the HVAC system to rule out any issues with the heating system.

Let us know how it goes.

Regards,
Mark