Need help in connecting humidifer to Nest 3rd Gen Thermostat

[WisconsinBill]

I was told the Nest Learning Thermostat can control an all-house humidifier which is connected to my furnace.

My current GLAS (by Johnson Controls) thermostat has the following wires:

BLUE - C Terminal

RED - RC terminal

WHITE - W1 terminal

ORANGE - AUX terminal

GREEN - G terminal

YELLOW - Y1 terminal

The Orange wire currently controls my humidifier.   The GLAS thermostat controls the humidifier and this is the wire that is used.

Connecting these Wires to the Nest Learning Thermostat:

Blue, White, Red, Green, Yellow are obvious, they connect to the terminals with the same name on the Nest.

It's the Orange wire that controls my humidifier that I am unsure about.

Referring to the Nest Wiring Diagram here:    Nest-Pro-Installer-Guide.pdf

Does my Orange wire just connect to the Nest "*" (star) terminal?  

The diagram on Page 18 of the Installer Guide has me confused since I only have 1 wire to control the humidifier, not two.   No Wire connected to the RH terminal on my current thermostat.

Please don't just advise me to get a Pro to install this thermostat.  I will be installing it, I am pretty sure the orange wire which controls the humidifier is connected to the Nest "*" terminal but I am just looking for someone to confirm this.

Thanks for your help!!

Bill

[Markjosephp]

Hello WisconsinBill,

Thank you for reaching out. I understand the wiring setup can be confusing, but I'd be happy to take a look into this for you.

If you don't have a heat pump system, heat pump systems sometimes have auxiliary heat to help heat your home more quickly or to help your home when it's too cold outside for your heat pump to run. To ensure the orange wire function, could you please check or take a photo of your system's control board? Once you've verified that it was for your humidifier, connect it to the * (star) terminal in the Nest Thermostat.

Please be advised that we strongly suggest a professional installation for this system because incorrect setup, either due to miswiring or wrong software settings, can cause weird HVAC behavior and even damage it.

Let me know how it goes.

Regards,

Mark

[Markjosephp]

Hey there,

I wanted to see if you still needed help. Please let us know if you have any other questions or concerns.

Thanks,

Mark

[Markjosephp]

Hi WisconsinBill,

I'm checking in to make sure that you've seen my response. Please let us know if you have any additional questions or concerns before I lock this thread in 24 hours. 

Thanks,

Mark

[WisconsinBill]

Mark, I will take a picture of my control board and send it to you.  I can confirm that the Orange wire DID control the humidifier with my old thermostat.   I just am trying to confirm that the Nest has the same functionality in controlling the humidifier with this wire.

Thanks,

Bill

[WisconsinBill]

OK, Here is a picture but I really don't see the orange wire or what it connects to.  But as I said in the last message, this wire definitely controls the humidifier. 

[Markjosephp]

Hey there,

Thanks for letting me know, WisconsinBill. It appears you have a standalone humidifier that is separate from your HVAC control board. If the orange wire is specifically for your humidifier, connect it to the */Star terminal for configuration.

If there’s anything else I can help you with, please let me know.

Regards,

Mark

[Jake]

Hey there,

I wanted to check in and see if you managed to see Mark's post. Please let me know if you have any questions from here. I would be happy to assist, and make sure you are good to go.

Best regards,
Jake

[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