Outside temperature T wire

[a_daga]

Hello,

My wiring in Lenovo thermostat has 2 wires labeled as T. I understand T means outside temperature sensors. Not sure why 2 wires though.

Nest learning thermostat has no provision for connecting these, should I just leave these unconnected?

Regards

[Markjosephp]

Hello a_daga,

Thanks for reaching out to the Google Nest Community page. I'd love to help.

The Nest thermostat does not need the T wires. Install your Nest thermostat without these wires since it uses its LCD display instead of an indicator light and gets sensor information, like outdoor weather conditions, over Wi-Fi.

Please let us know if you have more questions in mind.

Best regards,

Mark

[Markjosephp]

Hey there,

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

Thanks,

Mark

[a_daga]

Hi Mark,

Thanks for the response and the follow up. So I understand that temperature via outside sensors is not needed as Nest will get temperature over the internet.

I have read articles that say Nest can support heat pump and how to set up balance point with auxiliary heat (some sort of electric strip inside heat pumps). But there are also articles that say for heat pump + gas furnace (which would be the most common installation type ) Nest suggest professional installation as this is considered dual fuel solution.

Con you please confirm if Nest can support a dual fuel system, basically a heat pump + gas furnace and are there instructions on balance point setting for this?

[Markjosephp]

Hello a_daga,

Nest Thermostats will work in a dual-fuel system with a heat pump and a separate heater, but Heat Pump Balance will not be available. Instead, you can set a lockout temperature manually in the Nest thermostat's Equipment menu. Also, the requirements for the dual-fuel configuration should be evaluated by an expert because choosing the wrong options for a dual-fuel system can cause damage to your system. Contact a local pro to better assist you with the installation.

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

Thanks,

Mark

[Markjosephp]

Hey there,

Checking back in — how's it going? Still need our help? Let us know so we can assist you right away.

Best,

Mark

[Markjosephp]

Hi a_daga,

I'm just 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