Failure with Nest thermostst

[rgaila]

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Original Poster: Trevor Neal 

To Google Support  re Nest thermostat malfunction

We have a 2nd generation Nest Learning Thermostat, mounted on a base, that has suddenly failed, after a number of years of faultless service.

I have tried the usual HeatLink reconnection, including inputting the six digit code to the thermostat but there is still no connection.  Neither the HeatLink nor the thermostat were moved from their usual positions.

Initially the thermostat showed a W5 error, but this was not resolved after moving it closer to the wireless router. I might point out that other wi-fi devices work, and mobile phones and laptops all connect to the router. The router has not been changed and the wi-fi signal by the HeatLink is strong. I have checked the info on the thermostat, in particular the battery voltage, which shows 3.963V. Restart, presumably with any software update (it is 5.9.4-5), has not resolved the failure. Clearly nothing will change without a wi-fi network connection.

The thermostat now shows an H1 error code and the HeatLink status light remains yellow.

I have moved the thermostat close to the HeatLink but there is still no resolution of the failure.

I have read through threads posted by other users and have tried some suggestions, but all to no avail. It therefore seems that there is an irreparable failure in the thermostat, and I therefore ask you to replace the unit.

I look forward to your reply,

Trevor Neal

[rgaila]

Hi Trevor,

Thanks for reaching out. Unfortunately since this is a 2nd Generation Thermostat and we don't produce them anymore, a replacement would not be possible. Please check if it's not a 3rd Generation instead, by checking the back of the display and seeing if there's a long number starting with 09 (the serial number). As for the H1 issue, here are some steps you could try: 

1. Restart the Heat Link

• Hold down the Heat Link’s button until its light turns off. It should take about ten seconds.
• Release the button and wait for your Heat Link to restart.
• The status light will turn green if it re-connects to your thermostat. If the status light is yellow, continue to step 2.

2. Move your thermostat and test the connection

Your thermostat may be a bit too far away from the Heat Link or there may be something interfering with the wireless connection. Check that there isn’t anything physically between your Heat Link and thermostat, like a large mirror or refrigerator. Large objects made of metal or other dense materials can block wireless signals.

3. Reset the Heat Link to defaults

• Press and hold Heat Link's button for about 20 seconds. The Heat Link's status light will turn off, then it will start quickly blinking yellow. Release the button.
• When the factory reset is complete, the Heat Link's status light will pulse yellow and green.
• Normally, a Heat Link should automatically reconnect to your Nest thermostat after you reset it to factory defaults. Wait a few moments and then check your thermostat to confirm.
• If your thermostat asks for a pairing code, look on the bottom of Heat Link for the 6-digit code.
• If your thermostat is showing a code, go back to the beginning of this troubleshooter to troubleshoot that code.

Let me know how it goes.

-From Andreea, Community Specialist.