topic Re: connection problems in Nest Thermostats

connection problems

drew5 — Tue, 15 Aug 2023 11:02:02 GMT

Here's the present Honeywell thermostat. The green wire is not used here but the Nest info implies that it's needed. Can anyone tell me how to properly connect this nest thermostat? Or is it even compatible? I tried connecting the brown wire to the OB nest but that didn't work. It said, "Low Power." Please help.

Re: connection problems

HVAC — Tue, 15 Aug 2023 16:34:01 GMT

Your white wire goes to o/b on the nest. The brown wire goes to G. You need to connect C on the nest and at your air handler control board if green wire is at connected you can use it. Upload a pic of air handler wire connection to confirm. Good luck

Re: connection problems

drew5 — Tue, 15 Aug 2023 16:43:56 GMT

The unit is on the roof. I can't get up there. Is it critical to check the control board out if it runs using your connection?

Re: connection problems

HVAC — Tue, 15 Aug 2023 16:54:41 GMT

Need to confirm what wires are connected on the unit. Normally green wire is used for fan & connects to G on thermostat & unit controls not sure why they connected the brown but it’s fine as long as it’s connected to G at unit also. If the green wire is not used that’s what you can use to connect to C on nest and unit that’s what provides constant power to nest along with the red wire which is already connected. Might need a tech to do it for you if you can’t get to unit on roof. Good luck

Re: connection problems

zoeuvre — Fri, 18 Aug 2023 21:29:04 GMT

Hi folks,

@drew5, thanks for posting here in the Community forum and for showing interest in our Nest Thermostats.

I want to take a closer look at your system. Please send us a photo of the HVAC control board where the other end of the thermostat wires are connected. This will help us determine what went wrong after you installed the Nest thermostat you have.

I appreciate your help, @HVAC.

Best,

Zoe

Re: connection problems

drew5 — Fri, 18 Aug 2023 22:52:01 GMT

I would take a photo but I just had a knee replacement today and the unit is on the roof.

Re: connection problems

drew5 — Fri, 18 Aug 2023 22:53:44 GMT

I guess Ill have to get a tech out.

Thanks.

Re: connection problems

zoeuvre — Sat, 19 Aug 2023 17:24:59 GMT

Hi drew5,

Thanks for keeping me in the loop. We want to make sure that everything will be taken care of. I’ll keep this thread open and wait for your update after you reach out to our Nest Pro technician that you can contact from here.

Thanks,

Zoe