Are there different generations of the Nest thermostat E?

[Johncat55]

Hi, 

I have 2 Nest thermostat E’s that have been working well for many years with my two-wire Taco circulation controller.  I would like to add two more, but I’ve learned that the newer Nest  thermostats (not e), require a C connection or power adapter. I’ve tried these new Nest thermostats and consulted with Taco industries and could not make them work. I’m hoping that the E has not changed and I can use them instead.  
Any help would be appreciated. Thanks!

[Markjosephp]

Hello Johncat55,

Thank you for taking the time to let us know about your inquiry. I'd be interested in learning more.

A few questions: could you send us a picture of the wiring on your current thermostat? Do you have a zoned system? Also, the Nest Thermostat (model 2020) often requires a C wire to work, though there are cases where it might not be needed. You might also use our compatibility checker to determine if the Nest Thermostat works with the setup you currently have.

I'll look forward to your response.

Regards,

Mark

[Johncat55]

Hi Mark, 

thanks for your response.  We have had our nest e thermostats for many years now. I only have a red and white wire connected as our zone controller has no “c” wire available.  I recently purchased one of the newer thermostats (with the mirrored front) and hooked it up with the power adapter but it does not work properly. That’s why I am hoping to find older units identical to what I currently own, but I don’t know how to distinguish them from the latest models

[Johncat55]

 

[Markjosephp · Accepted solution]

Hi there,

Thanks for letting me know, @Johncat55. I understand that you already had the Nest Thermostat (2020) version installed, and I'm sorry to hear that it doesn't work as you expected. To learn more about their differences, please take a look at this article. Also, the Nest Thermostat E is available through Nest Pros only. Check out this link on how to contact the Nest Pro and let us know if you have more questions or concerns.

Regards,

Mark

[Johncat55]

Thanks Mark! That answered my question .

[Markjosephp]

Hi Johncat55,

That's great! I'm delighted you found the answer you were seeking. Therefore, this thread will be closed in 24 hours unless I can help you further.

Best Regards,

Mark