Nest 4th Generation Learning thermostat not starting.

[skk960]

Trying to replace my Emerson thermostat with a Nest 4th generation learning thermostat. Emerson has a jumper connecting RH and RC.

Here is my connection configuration and Nest didn't turn on, blank display. Emerson works just fine.

Red Wire -> Rh
Yellow -> Y1
Green. -> G
White. -> W1
Blue. -> C

I tried connecting Red Wire --> Rc also and no luck.

What is the W/E ? I don't see any equivalent in Nest for W/E. Thought it was only for Emergency power for a second source and I believe I don't have a one.

Any one replaced the Emerson with Nest 4th Generation successfully ?

Thanks & Best Regards
Kamal

Base PlateRh-Rc Jumper

[Patrick_Caezza]

@skk960 

It should just be straightforward.

Red - RC to Rc

Yellow - Y to Y1

Green - G to G

White - W/e to W1

Blue - C to C

Try removing the thermostat from the Home app, do a factory reset, and set it up again.

[skk960]

Still nest gen4 didn't like the setup. Old thermostat works fine. 

Thanks 

Kamal 

[moralesvicente]

Hello skk960, 

Thanks for reaching out to the Google Community Forum. I’m sorry to know that you’re experiencing wiring or system troubles with the Nest Learning Thermostat (4th generation). No worries; I’m here to assist you. 

Here are some recommendations that you can follow: 

• Check the system power: Ensure the power to the system is on. The power switch is usually in the breaker box, but in some homes, it’s like a light switch near the HVAC equipment. There may be one or two switches, one for heat and another for cool. Make sure the power is on for both, then check the thermostat. 
• Inspect the thermostat wiring:

1. Remove the thermostat display.
2. Ensure that the wires are in the correct terminals.
3. Ensure that each wire has ⅜ inch (9.5 mm) of exposed wire.
4. Ensure that each wire is properly seated.
5. Turn on the power to the system, then check if the thermostat works.

Then try to setup the device again; remember to delete the thermostat from the Google Home app. 

I'll look forward to your response.

Best regards,

Daniel