Last Friday I upgraded my Ecobee thermostat from a 4 to their new one. I removed it from the Ecobee app and it shows up no where in there. I have also reloaded several times but the old thermostat will not disappear.and there is no option to manually delete it. All I can do is disable it. All the room sensors are associated to the new thermostat, so that cannot be a factor.
Thanks to Gemini for the technique. Worked perfectly. Back up the file just to be safe.
Open your File Editor (VS Code Server or the standard File Editor add-on).
Note: If you use the standard File Editor, you may need to go to the add-on configuration and turn off “Enforce Basepath” or ensure it allows you to navigate up to the hidden .storage folder.
Navigate to the folder /config/.storage/.
Open the file named core.device_registry. (You should probably back up the file first.)
Ctrl+F (Find) and search for the name of the old thermostat (e.g., “Old House Downstairs”).
You will see a lines of JSON code that look roughly like this:{ "area_id": null, "configuration_url": null, "config_entries": [ "some_long_random_string" ], "connections": [], "disabled_by": null, "entry_type": null, "hw_version": null, "id": "another_long_random_string", "identifiers": [ [ "ecobee", "123456789101" ] ], "manufacturer": "ecobee", "model": "ecobee3 lite", "name_by_user": null, "name": "Old Thermostat Name", "sw_version": "4.6.33.128", "via_device_id": null },
Delete that entire line.
Watch out: If it is the last item in the list, there won’t be a comma after the closing brace. If it is in the middle, there will be. Maintain valid JSON syntax (commas between items, no comma after the last item).
Repeat for any other old thermostats in that file.
I have mine running on a Raspberry PI and I cannot seem to find the /config/ folder at the / root or within /homeassistant/ and U di gave “Enforce Basepath” disabled.