Nest not compatible

[Mtnroads]

Carved out time, tools, all set to install Nest Thermostat on heat pump system. After going through setup .... Nest not compatible with system. 

My wires to heat pump contacts:

R (red),Y (yellow),C (blue),O/B (orange),G (green),AUX/E(brn&wht)

Any ideas?

[heysylvester]

From what you've said about your current wiring setup, the Nest Thermostat should be compatible with your system. Have you verified the colors match the wiring inside of the heat pump? Additionally, the Nest Thermostat will detect incompatibilities based on your answers in the app while setting it up. Take a moment to go back to the app and check what system information you input, then try again. If you need further help, please post a picture of the wiring inside the heat pump, and a photo showing how it's connected to the Nest Thermostat.

[Mtnroads]

Thank you heysylvester. I'll try the app setup again. But tracing wires in the heat pump intimidates me. 

[Mtnroads]

The app gave me the same result. Also, cannot figure out how to attach a photo. 

[Mtnroads · Accepted solution]

Here are my existing wires.

 

[zoeuvre]

Hi folks,

@Mtnroads, thanks for posting here in the Community forum and for showing interest in our Nest Thermostats. In your case, the presence of the "AUX/E" wire suggests that you have a heat pump system with auxiliary or emergency heat. However, your current thermostat has two wires connected to the AUX/E terminal, while Nest Thermostat requires them to be separately connected to its base.

What is the make and model of your HVAC system? And could you check on your HVAC control board and see to what terminals these brown and white wires are connected? I'll look forward to your response. 

I appreciate your help, @heysylvester. 

Best,

Zoe

[Mtnroads]

Thank you Zoe.

My heat pump is a Trane XL1400. Removing the side cover shows orange, brown, blue, yellow and red coupled to same color inputs. But, WHITE goes to Trane BLACK. 

I hope this tells you something because I don't know how to find the Trane circuit board. 

Don 

[jb76]

Hi - you should be able to match the wiring you have currently:
Keeping in mind the following for a heat pump
https://www.googlenestcommunity.com/t5/Nest-Thermostats/O-B-heat-pump-settings-reset-can-t-see-equip...

Here is a pic. of the wiring hookup to the Nest backplate for a heatpump system:
https://images.app.goo.gl/KZGqF7pnskmgVNXV8

J