topic Re: Confused my old system Wiring O and wired B in Nest Thermostats

Confused my old system Wiring O and wired B

tommycao108 — Sat, 29 Apr 2023 17:29:21 GMT

My old system have separated wire O and wire B, so how can I wire them to Nest Learning Thermostat?

Wire O and wire B issues

tommycao108 — Sat, 29 Apr 2023 17:11:26 GMT

My old system have separated wire O and wire B, so how can I wire them to Nest Learning Thermostat?

Re: Confused my old system Wiring O and wired B

Patrick_Caezza — Sun, 30 Apr 2023 01:57:01 GMT

@tommycao108

What is the manufacturer of the thermostat and HVAC?

I feel the Blue (B) wire is just a C wire.

Re: Wire O and wire B issues

Patrick_Caezza — Sun, 30 Apr 2023 06:03:29 GMT

@tommycao108

Post a picture of the current thermostat wiring.

Re: Wire O and wire B issues

tommycao108 — Sun, 30 Apr 2023 20:25:19 GMT

Re: Confused my old system Wiring O and wired B

tommycao108 — Sun, 30 Apr 2023 20:32:35 GMT

Re: Confused my old system Wiring O and wired B

Patrick_Caezza — Tue, 02 May 2023 06:18:15 GMT

@tommycao108

Give this wiring a try

White - O to OB

White - W to W2 (set as AUX heat)

Green - G to G

Red - R to Rc

Blue - B to C

Red - Y to Y1

Re: Wire O and wire B issues

Patrick_Caezza — Tue, 02 May 2023 06:19:03 GMT

@tommycao108

I answered your question in your other thread

Re: Wire O and wire B issues

Markjosephp — Fri, 05 May 2023 20:27:12 GMT

Hi everyone,

I've duplicated your thread in the main one here. You’ll receive all updates on this issue on the main thread, and we recommend updating and checking this thread when needed.

Best,

Mark

Re: Confused my old system Wiring O and wired B

Markjosephp — Fri, 05 May 2023 20:30:42 GMT

Hello folks,

I wanted to ensure that everything was covered here.

Thanks for looking into this, @Patrick_Caezza.

@tommycao108, a wiring guide was shared with you above. 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.

Best,

Mark

Re: Confused my old system Wiring O and wired B

tommycao108 — Fri, 05 May 2023 20:35:14 GMT

thanks for all of your help! But still didn’t display any signs. Shall I charge the nest’s battery first?

Re: Confused my old system Wiring O and wired B

Markjosephp — Tue, 09 May 2023 20:51:19 GMT

Hello tommycao108,

Uh oh! Could you share with us a picture of how you installed your Nest Thermostat? Also, please try charging the thermostat display for an hour and waiting until it turns on.

Keep me posted.

Regards,
Mark

Re: Confused my old system Wiring O and wired B

Markjosephp — Fri, 12 May 2023 20:58:17 GMT

Hi tommycao108,

I'm checking back in — how's it going? Still need our help?

Regards,

Mark

Re: Confused my old system Wiring O and wired B

Markjosephp — Sat, 13 May 2023 21:04:04 GMT

Hello tommycao108,

It has been a few days since your last reply, and we're going to lock the thread within 24 hours. If you have any questions, please feel free to create a new post.

Thanks,

Mark