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Lack of a C wire

kjdiver
Community Member

So my system is simple, heat only/one zone. It has no C wire so I got the "nest power connector"  but can't find the "common" connector to plug into. In reading the manual for the boiler it says DO NOT supply 24v power to the Tstat circuit. Does that mean my system is not compatible with Nest?nest.jpg

14 REPLIES 14

Jhonleanmel
Community Specialist
Community Specialist

Hi kjdiver,

 

Thanks for posting and for the image ― let's get this sorted out.

 

It seems that you have a communicating thermostat which is not compatible with our Nest thermostats. However, we have several users who were able to successfully set up one after rewiring their system. Please contact a pro installer to discuss your options.

 

Best, 
Mel

EdwardT
Community Specialist
Community Specialist

Hi kjdiver,

 

I wanted to follow up and see if you are still in need of any help. 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.

 

Thanks,

Edward

 

kjdiver
Community Member

Hi Edward! I have a Transformer arriving today, it's 24v and plugs into a standard outlet with 2 wires heading to the tstat I know one of the wires will go to C I just don't know where the other should go ..Y, W, G, R or OB..I have a single-zone heat-only system. Any thoughts?

EdwardT
Community Specialist
Community Specialist

Hi kjdiver,

 

Thanks for the response. Could you share the the make and model of this transformer so I could take a look?

 

Thanks,

Edward

kjdiver
Community Member

24 Volt Transformer, C Wire Adapter for Nest Honeywell Ecobee and Sensi ThermostaDoorbell Transformer for Nest Hello Doorbell and Any Doorbells Require 24V Power Supply

kjdiver
Community Member

 

This is the 24v transformer

 

IMG_1386.jpg

EdwardT
Community Specialist
Community Specialist

Hi kjdiver,

 

Thanks for the response. In some cases, the wire with the black stripe would go to the C terminal and the other wire would go to the R terminal. I would suggest referring to the manual of your adapter to make sure that you're wiring it correctly.

 

Thanks,

Edward

Jeran
Community Specialist
Community Specialist

Hey there kjdiver,

Do you have any more questions or need any additional help? 

Thank you,
Jeran
 

kjdiver
Community Member

Hey Jeran, I took the week off from this "little" project lol, and now I'm back at it. So the general feeling is the transformer wires, the black and white go to the C terminal and the other solid white goes to the R terminal along with the red from the furnace with the remaining white from the furnace going to the W terminal?

EdwardT
Community Specialist
Community Specialist

Hi kjdiver,

 

Thanks for the response. That's correct. You can also check this other thread regarding this.

 

Thanks,

Edward

kjdiver
Community Member

Not looking to celebrate too soon,  but....it looks like that WORKED!!!! Thanks for all the help!!

Jhonleanmel
Community Specialist
Community Specialist

Hey there, 
 

@EdwardT, thanks for the help.

@kjdiver, awesome — glad to hear that your issue is fixed. It looks like we can consider this one complete, so I will lock the thread shortly unless I can help out with anything else. 

Best, 
Mel

kjdiver
Community Member

Yes... thanks for all the help!

Jhonleanmel
Community Specialist
Community Specialist

Hi kjdiver,

 

As we got our resolution here, I'm going to mark this thread as resolved. I'll be locking this thread now.

 

Feel free to create a new thread if you have more questions or have other concerns in the future.

 

Cheers,
Mel