Wired Nest G3 to replace Ruud 7 wire - doesn't heat

[Han10]

I installed a Nest 3rd Gen to replace my Ruud 7 cable system (G, R, B, Y, W2, X, E). The thermostat says is heating but it does not.

R to R
G to G
B to OB 
Y to Y1
X to C
W2 to W2/Aux*
E to ?* I ended up combining E & W2 and placed them in the W2/Aux terminal

I already switched the heat pump orientation to B. The fans blow, when I test Aux heat, there is a bit of warmth but when I use the thermostat and try to heat, the air blows but s not hot (or warm).

Can someone please help me? Thank you.

[kcruzgonzalez]

Hello, Han10 

Thanks for reaching out to our Nest Community. We are so happy to assist you with your questions about the Nest Thermostat 3rd Gen.

To assist you in the best possible way, I would like to know if you can send us a photograph of the wiring you had before installing the Google Thermostat so we can identify and provide you with the best assistance for your questions.

Please keep me posted. I'll look forward to your response.

Regards,

Kevin

[Han10]

Happy to, how do I upload my photos?

[kcruzgonzalez]

Hi Han10,

Thank you for your response. Let's work together for a solution.

If on your cell phone the camera icon is not appearing to attach photos, please try on a computer or any other device to be able to help you with this problem.

Please keep me posted. I'll look forward to your response.

Regards,

Kevin

[Han10]

Thank you for your response Kevin. I've attached the photos below. Initially I capped off the E wire since there was no terminal on the Nest for that. I live in GA, don't need emergency heat anyway. Seeing that it didn't work and after some additional research, I combined E and W2 and placed them into the W2/Aux terminal (that's what you see in the photo). The system didn't heat at all. I have family in town and need heat so I put the old thermostat on and voilà it starts heating again. Please help.

Old systemNest-

[kcruzgonzalez]

Hi Han10,

Thank you for your response. I'm sorry to hear that you're going through that situation right now. Let's work together for a solution.

Let me assure you that it's not necessary to connect all the wires in your system. Let's try placing the wires as follows. Please follow the image.

Let me know how it goes and keep me posted.

Regards,

Kevin

[Han10]

Hey Kevin, 

Thanks for the quick response. I am color blind so the photo doesn't help me much and also the colors don't really match. i.e. I don't have a blue C but some sort of green or brown X.  Would don't mind would you kindly direct me from the first photo using the letters i.e.

Y cable on old thermostat to Y1 on nest

G to G

W2 to W1?

X to C?

R to Rh?

B to ?? (capped off?) My system is a heat pump, does this not need to be connected?

E to ?? (capped off?)

My HVAC unit is a Ruud model number UBHC-17J11NFD serial no T M2103 02413

The box on the bottom says Model RCBA-3765G17 serial M2103 

Again, thank you very much Kevin.

[kcruzgonzalez]

Hi Han10,

Thank you for your response. Let's work together for a solution.

Please connect the wires in this order: 

• G to G 
• W2 to W1
• X is not compatible with our system.
• R to Rh
• B to C 
• E is not compatible with our system.

If the issue persists, please contact a local technician to make it compatible because you have different wires that are not compatible with our Nest Thermostats.

Let me know how it goes and keep me posted.

Regards,

Kevin

[Han10]

Thank you for your response. Yes, let's work together:

Would you kindly explain to me how B would work with C? I was under the impression B wire was for the heat pump.

Also, I measured the X cable with a voltmeter and it was at 28 volts so I thought that would go in to the C. Is that not the case?

Thank you.

[kcruzgonzalez]

Hi Han10,

Thank you for your response.

To avoid damaging your Google Thermostat, I would like to recommend you contact a pro installer since you have some wires that are not compatible with our system and let you know the article where we describe what wires are compatible with our devices. Please read how to identify a thermostat wire, and also a trained professional can quickly tell what kind of system you have and identify the wires. They can also install and set up your Nest thermostat for you and answer any questions you have. Contact a local professional in your area to service your system. 

Let me know if you have any further questions.

Regards,

Kevin

[Han10]

Kevin, I feel like you gave up on us. I thought we were going to work on this together. No need to involve outside professionals. We can get this done. I have done a lot of research, don't need to pay someone on the outside $160.

With a little bit of focus I am certain you can come up with the correct wiring.

What is the next move?

[kcruzgonzalez]

Hi Han10,

Thank you for your response. in regards to the last questions about the B wire.

• Check the B wire color.
  The colors of thermostat wires often don’t adhere to industry standards, but they can sometimes provide a clue in certain situations. If your thermostat doesn’t have a separate connector labeled C and you’re not sure what type of system you have:
• A brown wire is most likely a heat pump wire and should be connected to the O/B connector on the Nest thermostat. 
• If the B wire is blue, it should most likely be connected to the C connector.
  Note: In the first picture, the B wire is blue, and the X wire looks brown, but we are not sure if the X wire is compatible with our system since in our resources we don't have instructions related to any X wire.

Please connect the wires in this order: 

• G to G 
• W2 to W1
• X is not compatible with our system.
• R to Rh
• B to C 
• E is not compatible with our system.

Let me know if you have any further questions.

Regards,

Kevin

[Han10]

So you just repeated what you had two answers ago. 
Not compatible with our system is not a valid answer. Just because it has a different letter to identify it you can’t just decide it’s not compatible. 
You have not provided an ounce of value. I am not any better off than I was before we started this incredible exercise of wasting time. 
Is there someone that I can chat with that may know what they are doing?

[kcruzgonzalez]

Hi Han10,

Thank you for your response. 

What I tried to say is that it is not necessary to connect those wires to your thermostat because, as I mentioned and shared the article with you so you could identify if your current system was compatible, it indicates that we should not connect those wires since we do not know their function, they have colors that do not match, and you also made a valid point: you have different letters. Please connect the thermostat as I sent it to you last time and let me know if it works. If it doesn't work, we can look for another solution. I really am trying to help you with this problem.

Feel free to reply to this post when you complete it. We are happy to help you.

Regards,

Kevin