What is the brown wire going into the separate holder?

[FedeBongio]

I bought a Nest Learning thermostat 4th generation.

This is what my old thermostat connections look like: https://photos.app.goo.gl/cLbXnrbDxs3pUKab7

does the fact that the brown cable goes into a separate rack matter? Do the experts see any concern with mixed colors? im planning to connect following color convention.

thanks in advance!

[Patrick_Caezza · Accepted solution]

@FedeBongio 

No, it doesn't matter that it goes to a separate terminal.

I can't read the printing behind several of the wires. Can you post what they are?

[Patrick_Caezza · Accepted solution]

@FedeBongio 

Do you know if you have a heat pump or a conventional Furnace?

Give this wiring a try.

White - W to W1 if you have a conventional furnace, or W2 if you have a heat pump

Yellow - Y to Y1

Green - G to G

Red - R to Rc

Brown - C to C

Blue - O/W2* to W2 if you have a conventional furnace, or OB if you have a heat pump

[Patrick_Caezza · Accepted solution]

@FedeBongio 

No, it doesn't matter that it goes to a separate terminal.

I can't read the printing behind several of the wires. Can you post what they are?

[FedeBongio]

Thank you for your response @Patrick_Caezza ! These are the printing behind the wires:

• White wire says: W
• Yellow wire says: Y
• Green wire says: G
• Red wire says: R

Now it gets interesting

• Brown wire (on the separate holder) says: C
• Blue wire says: O / W2*

Does this help?

[FedeBongio]

@Patrick_Caezza what do you recommend? I might try to install it on the weekend! thank you!

[Patrick_Caezza · Accepted solution]

@FedeBongio 

Do you know if you have a heat pump or a conventional Furnace?

Give this wiring a try.

White - W to W1 if you have a conventional furnace, or W2 if you have a heat pump

Yellow - Y to Y1

Green - G to G

Red - R to Rc

Brown - C to C

Blue - O/W2* to W2 if you have a conventional furnace, or OB if you have a heat pump

[FedeBongio]

Thank you!

@Patrick_Caezza I have a Carrier Weathermaker 8000 ts furnace (which as I understand is used as a fan for the AC too), so I'll follow your recommendation as a conventional furnace. 

Will let you know how it goes, thank you again!

[Patrick_Caezza · Accepted solution]

@FedeBongio 

That is a correct assumption.

[FedeBongio]

Just came back here to say it worked perfectly following your guidance. Thank you so much @Patrick_Caezza !!!