Google Nest first generation showing intermittent Error code E298.

[Rmr882]

Hi, Google Nest thermostat has been “intermittently” showing  No Power with error code E298.  I connected extra wire to Common on both furnace and Thermostat hoping to resolve this issue.  Query of wiring diagram shows all wires are working, however, I still get the above error code.  Went through the trouble shooting guide, nothing out of the ordinary.  Any ideas?

[CoolingWizard]

E errors a typically a wiring problem.  You saying that the Nest recognizes all the connected wires and all wedges are Green?

Ac Cooling Wizard

[Rmr882]

YCWGR are all blue.  I have a first generation Nest.

[CoolingWizard]

If I remember correctly, on the first generation, it shows you wires with checkmarks in boxes, I think

AC Cooling Wizard 

[Rmr882]

I have version 1.1-11. 

[Rmr882]

[Rmr882]

I noticed that I had to constantly replace the batteries.  After researching, I added the COM (lavender wire) at both ends.  Still indicates intermittent “No Power E298.”

[CoolingWizard]

Do you have a Volt Ohm Multimeter? If so, at the thermostat check AC power between R and C wires.  

AC Cooling Wizard

[Rmr882]

Shows 27.7 volts.

[CoolingWizard]

Well, then allis good. Make sure the wires, the bare copper ends, are straight and fully inserted.  Other than that, there is not a reason for this E type error.  My Nest Pro manual does not show me an E error with that high of a value.  

The AC Cooling Wizard

[Rmr882]

Appreciate your quick response.  I’m a novice when it comes to electrical and this was a big help.

[Markjosephp]

Hello folks,

I wanted to stop by and see how I could help.

Thanks for your expertise, @CoolingWizard.

@Rmr882, I did come across a useful article that provided some troubleshooting advice for when your thermostat shows an E298 or M29 message code. Please let us know if you need more help.

Regards,
Mark

[Rmr882]

Thanks Mark, at your convenience please send the link for the article.

[Markjosephp]

Hey there,

Oops! I forgot to attach it, but here you go. Please take a look at this link and let me know if you have more questions.

Best,
Mark

[Rmr882]

Thanks Mark, I had seen that article and was also able to troubleshoot  with cooling wizards expertise. Now I’m just monitoring.

[Markjosephp]

Hello again,

Perfect! Thanks for letting me know, Rmr882. In the meantime, continue monitoring it and keep us posted on how it goes, as I would be glad to know what the result would be.

Best,
Mark

[Markjosephp]

Hi Rmr882,

I'm checking back in — how's it going? Still need our help? 

Thanks,

Mark

[Markjosephp]

Hello Rmr882,

It has been a few days since your last reply, and we're going to lock the thread within 24 hours. If you have any questions, please feel free to create a new post.

Thanks,

Mark