Neat compatibility

[ABC123]

Would the nest be compatible with these wires ?

 

 

[Patrick_Caezza]

Your current thermostat is only compatible with the Nest 3rd GEN Learning Thermostat.

I would suggest wiring it like this.

White - C to C

Orange - B/O to OB

Brown - G to G

Blue - A to ? (possibly an Accessory of some sort.)

Red - E to * (set as emergency heat)

Yellow - Y1 to Y1

Black - RH to Rc

Without knowing more about the make and model of this thermostat, I can't give you a suggestion on where to connect the Blue "A" wire.

[ABC123]

• Hi here’s a picture of the thermostat model 

   

[ABC123]

Hi Patrick,

this is a copy of the manual can it help you further confirm all wiring ?

 

[sporfrog]

Thanks for posting the thermostat info! It looks like with that thermostat A and E are different fans speeds (med and low). It's a bit rare to have those wires.

Since all the other connections seem standard it is possible (I don't know for sure) that you could use a Nest, but may have to settle for a single fan speed control from the thermostat. However, Google recommends pro installation for systems with multiple fan wires.

From Fan compatibility with Nest thermostats

If your system has more than one fan wire, you should contact a nest pro to have your Nest thermostat installed. Incorrect installation settings can damage your system, your Nest thermostat or both. Some systems that need to be installed by a Nest Pro include systems with G2, G3, GM, or GH wires.

Maybe @Patrick_Caezza has some ideas?

[Patrick_Caezza · Accepted solution]

Ya, my original wiring suggestion won't work with your setup.

Try this wiring.

White - C to C

Orange - B/O to OB

Brown - G to G

Blue - A to Y2 (2nd-speed fan relay)

Red - E to * (3rd-speed fan relay)

Yellow - Y1 to Y1

Black - RH to Rc

You might have to swap the Brown and Red wires in case the thermostat thinks the brown wire is for low speed

[MelbaDT]

Hey folks, 

Thanks again for taking care of this, Patrick_Caezza and sporfrog. 

ABC123, I'm dropping by to check if everything is good here. Let us know if you still need some help. 

Best, 

Melba

[MelbaDT]

Hey ABC123, 

I haven't heard from you in a while so I'll be locking this thread if there is no update within the day. Should you have any new issues, updates or just a discussion topic, feel free to start a new thread in the community.

Best, 

Melba