Nest wiring common question

[Deludwig]

So I have a hydronic radiant heat only system. T stats wire is 4 wire (r,w,o,b) but only r & w used with current dumb stats. I tried using the orange as a common by wiring it to the “c” connector on stat and the Com screw terminal on the taco relay system end. Still getting the no power error?

[Jake]

Hey there,

Sorry to hear about the trouble. I wanted to follow up and see if I could be of any help. I found an article with some troubleshooting steps if you are getting no power. Please let me know if you are still having any trouble from here, as I would be happy to take a closer look and assist you further. 

Best regards,
Jake

[Jhonleanmel]

Hi folks,

Chiming in to see if you still need assistance with this. Let us know if you have additional questions ― we'd love to help.

Best,
Mel

[Deludwig]

Still have not solved this

[Jhonleanmel]

Hi Deludwig,

Thanks for getting back to us. Could you confirm which country are you posting from?

Thanks,

Mel

[Deludwig]

US. I am in MA

[EdwardT]

Hi Deludwig,

Thanks for the response. I'd love to know more about this. Could you check the control board of your HVAC system so we could see where the other end of the wiring are connected to? Also, please share a photo of the wiring of your current thermostat.

Thanks,

Edward

[EdwardT]

Hi Deludwig,

It's me again. I wanted to check back in to see if you have other questions and concerns. Feel free to let me know if you do.

Thanks,

Edward

[Jake]

Hey there,

I wanted to check in, and let you know that I will be locking the thread in 24 hours.

Best regards,

Jake