topic Re: Nest compatibility in Nest Thermostats

Nest compatibility

Lp4 — Mon, 21 Nov 2022 19:22:07 GMT

I’m having difficulty figuring out the wiring. Can someone help

Re: Nest compatibility

CoolingWizard — Mon, 21 Nov 2022 20:10:13 GMT

I see know wire on that, and that is not a Nest Thermostat.

Ken, The AC Cooling Wizard

Re: Nest compatibility

Lp4 — Mon, 21 Nov 2022 21:48:03 GMT

No that is the old one I have 2 green wires GL and GH I sent that pic to show what wires I had. My husband did not take a pic before un-doing

Re: Nest compatibility

Lp4 — Mon, 21 Nov 2022 21:59:42 GMT

Got my old hooked back up right now. Just can’t figure out the wiring for the nest

Re: Nest compatibility

Lp4 — Mon, 21 Nov 2022 22:01:58 GMT

Re: Nest compatibility

CoolingWizard — Mon, 21 Nov 2022 22:38:54 GMT

Ok, the Nest Learning Thermostat 3rd generation can handle two fan speeds. The way you have them in your old thermostat has a White wire in GH and a green wire in GL. The second green wire is in W. The B wire is your Common. If you are confident of the wires and where you put them in your old thermostat base, here is what your input to the Google Nest Configurator.
R-Red Wire

C-Blue Wire (the wire on B)

GL-Green Wire

GH-White Wire

Y-Yellow Wire

W-Green Wire

Again, you need to upgrade to a Nest Learning Thermostat 3rd Generation in order to have support for two fan speeds. The Nest thermostat you showed a picture of will not support dual fan speeds. Now the configuration of your fan speed will be as follows, GH is for cooling with the air conditioner, and the GL is when you’re running the heater for heating the house. If it is not too much trouble, would like to get a picture of your furnace manufacturers label, which shows the model number, and a copy of the outdoor unit manufacture label that shows again the model number. It is not often that you find a thermostat that is controlling the blower speeds for heating and cooling separately. Generally the air handler with the heater in it, has a control board and that control board looks at the signaling wires coming in, specifically, W and G, and select the appropriate speed for the blower fan.

Ask any additional questions you have.

Ken, The AC Cooling Wizard

Re: Nest compatibility

Lp4 — Tue, 22 Nov 2022 12:53:38 GMT

Thank you very much for your answer I really appreciate it.

Re: Nest compatibility

Markjosephp — Fri, 25 Nov 2022 16:51:16 GMT

Hello everyone,

I appreciate your help here, Ken.

@Lp4, I wanted to ensure that everything was covered here. I did find a useful article about fan compatibility with Nest Thermostats; let us know if you have more questions.

Best regards,

Mark

Re: Nest compatibility

Markjosephp — Mon, 28 Nov 2022 17:28:58 GMT

Hi Lp4,

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

Thanks,

Mark

Re: Nest compatibility

Markjosephp — Tue, 29 Nov 2022 17:56:57 GMT

Hello Lp4,

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 close this in 24 hours.

Best,

Mark