Just Installed Nest - Getting Inexplicable T04 Error

[Cioffi]

Hey there, I *just* installed my Nest Learning Thermostat, Gen 3.

Everything looks to be wired up right, but when testing the HEATING, it just will not turn on.

Compared the wires/pins to the old, everything looks good and similar, and the breakers are all back on.

Not sure what additional steps to take?

[AriefAnshori]

Hi Cioffi,

If your Nest Learning Thermostat Gen 3 is not turning on the heating, here are a few troubleshooting steps you can try:

1. Check your wiring
   Double-check that your wiring is correct and that the wires are securely connected to the thermostat. Make sure that the wires are connected to the correct terminals on the Nest thermostat. You can refer to the Nest thermostat installation guide for more information.

2. Check the power source
   Make sure that the power source to the thermostat is working properly. Check that the circuit breaker for your heating system is on and not tripped.

3. Check the settings
   Make sure that your Nest thermostat is set to heating mode and that the temperature is set higher than the current room temperature.

4. Check for firmware updates
   Ensure that your Nest thermostat has the latest firmware installed. You can check for updates in the Nest app or on the thermostat itself.

5. Contact Nest Support
   If none of the above steps resolve the issue, you can contact Nest Support for further assistance. They can guide you through additional troubleshooting steps or arrange for a replacement if necessary.

It's important to note that working with electrical systems can be dangerous and it's always best to consult a professional if you are unsure or uncomfortable with the installation or troubleshooting process.

[Cioffi]

Did all this stuff right away, but managed to find and fix...

Even thought it was wired correctly when attempting to test heat, it was not wired correctly for a moment, and that screw everything up.

[AriefAnshori]

Hi Cioffi,

Glad to hear that you were able to identify and fix the issue with your Nest thermostat. It's not uncommon for wiring issues to cause problems with thermostat functionality, so it's important to ensure that the wiring is correct and secure.

If you continue to experience any issues with your Nest thermostat in the future, feel free to reach out Google Nest Help for further assistance.

[Jake]

Hey there,

Thanks for the help AriefAnshori.

I am glad to hear you were able to resolve the issue, and everything is good to go from here. With that being the case, I am going to go ahead and lock the thread in 24 hours. Please let me know if you have any questions from here, as I would be happy to review.

Best regards,

Jake

[Cioffi]

So, when installing, one of the wires came loose from it's housing, THAT was the issue. I noticed quickly, but not quickly enough, and my Nest thought it didn't have that wire, and at first, when testing Heat, wouldn't know that was wire was plugged in, but I guess a reset fixed it?