Nest power connector on learning thermostat gen 3

[shuoryang]

I have my learning thermostat gen 3 installed and it’s working as expected on the base. However I’m constantly getting wifi offline and could not remote control from my phone(the unit itself is still working). I checked the voltage and it’s showing around 3.6V. As there’s no C wire in my existing wires, so I added the power connector, but nothing seems changed, the voltage reading is still 3.6v and wifi is still not connected. I checked the voltage between the Y and R port from the connector and it’s showing 25V which seems correct. Could anyone advise what else can I check or change to make the powering work?

[Derickf]

Hi @shuoryang,

Thank you for posting in the community. I’m sorry to hear that your Nest Learning Thermostat (3rd Gen) is constantly offline, preventing remote control. I appreciate you confirming you've already checked the voltage, battery levels and installed the Nest Power Connector. I'm happy to assist.

To gather the necessary information, please answer the following questions:

• When did the issue first occur?
• Have you already charged the thermostat using a USB cable? If not, please plug your Nest Learning Thermostat (3rd Gen) into a USB port for one hour.

I'll be waiting for your reply.

Best regards,

Derick.

[shuoryang]

Hi @Derickf , thanks for your reply! This actually happened for quite a long time, I recently got to know the solution of the power connector and give it a try. I have tried charge the thermostat with usb cable and all function works after charging. However the app control and wifi connection will fail after sometime when the battery drained out. I can still use the unit itself directly to control my hvac system but couldn’t connect from the apps.

looking forward for your reply, thank you very much.

[Derickf]

Hey there!

Thanks for your reply. I appreciate you confirming that you already tried charging the Nest Learning Thermostat (3rd gen) using a USB wire and the battery is still draining even after you installed a Nest Power Connector.

Please follow the steps below:

1. Charge the Nest Learning Thermostat (3rd gen) with a USB wire again until the battery gets 3.9 volts.
2. Attach the Nest Learning Thermostat (3rd gen) to its base.
3. Disconnect the Nest Learning Thermostat (3rd gen) from the WiFi network for 24 hours, then check again the battery level and confirm if it is still draining.

Let me know how it goes.

Best regards,

Derick.

[shuoryang]

Hi @Derickf ,

I charged the nest thermostat using usb cable for 24 hours and put it back to base, with the wifi disconnected. Its voltage is now maintaining at around 3.8v.

thanks