@Josser 

Thanks for reaching out. I understand that after setting up your Deco Mesh system, your Carrier thermostats are intermittently losing their Internet connection, even though the initial setup went smoothly.

Here are some steps you can follow to troubleshoot this issue:

1. Check the Deco's LED light status:
• If the main Deco unit's light is solid red, there may be a connection issue between your Internet Service Provider (ISP) and the main Deco. In this case, please refer to troubleshooting for 'main Deco solid red'.
• If any satellite Deco units are flashing red, please refer to troubleshooting for 'satellite flashing red'.
• If all Deco units have green or white lights, proceed to the next steps.

2. Verify device access in the Deco app:
• Open the Deco app and go to MORE > Wi-Fi Access Control or Block List. Make sure your thermostats (and other affected devices) are not being blocked or managed by access control.

3. Check Parental Controls:
• Go to the Parental Control page in the Deco app. Ensure your thermostats are not included in any parental control profile that might restrict their Internet access.

4. Review DNS Server settings:
• Go to MORE > DHCP Server. Make sure both the primary and secondary DNS server fields are empty, unless you have a specific reason to set custom DNS servers.

5. Check VPN Client settings:
• Go to MORE > VPN > VPN Client. Confirm that your thermostats are not listed as VPN clients, as this could prevent them from accessing the Internet.

If you follow these steps and the issue persists, please let us know any additional details, such as whether other devices are also affected or if the problem only occurs with your thermostats. This will help us provide more targeted assistance.