wire Nest Thermostat with Trane XL80 heating furnace

[1824Paul]

[Houptee]

Trane calls the C wire B.

This appears to be a 2 stage heating system since you have W1 and W2 connected.

If you have the nest learning model you just match up the wires but B will be C on the nest.

If you have the regular nest model you have to put W2 into the OB * on the nest.

[1824Paul]

This did not work. I get a "no power" and "Error: E298," and "Wi-Fi disconnected" on the Nest. It does turn on the furnace. Would a Google Power Nest Connector be the solution? 

[EdwardT]

Hi folks,

@Houptee, thanks for the help!

@1824Paul, thanks for reaching out. I'm sorry to hear that you're having an issue with the installation of your Nest Thermostat. If you haven't yet, please try the troubleshooting steps on this link to isolate the issue.

Thanks,

Edward

[EdwardT]

Hi 1824Paul,

It's me again. I wanted to check back in to see if you have other questions and concerns. Feel free to let me know if you do. 

Thanks,

Edward

[Houptee]

Go to the firnace and remove the cover.

Locate the thermostat wires connecting to the furnace control board.

Take a picture of the wires showing the screws and the labels for each screw.

See if the B wire, your brown wire, is connected to the B or C screw on the furnace, this is required to provide power to the Nest along with the R red wire.

Also can you look on the back of the cover for the wiring diagram and locate in the diagram the thermostat wiring it will show the proper way the thermostat must connect to the furnace control board.

[EdwardT]

Hi folks,

@Houptee, thanks for the help!

@1824Paul, I wanted to follow up and see if you are still in need of any help. 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.

Thanks,

Edward

[EdwardT]

Hi 1824Paul,

I'm just checking in to make sure that you've seen our response. Please let us know if you have any other questions or concerns as I will be locking this in 24 hours.

Thanks,

Edward