Connect via Thread

UltimateSensor Mini v2 uses an ESP32-C6, which has a built-in Thread radio. With the dedicated Thread firmware variant the sensor joins your existing Thread network and talks to Home Assistant over IPv6 through your Thread border router, with no WiFi needed.

Local only. The Thread firmware connects to Home Assistant directly and does not include the SmartHomeShop cloud. If you use the SmartHomeShop app, keep using the WiFi or Ethernet firmware.

What You Need

Good to Know Before You Start

• No SmartHomeShop cloud over Thread. Thread devices live in an IPv6 mesh without regular internet access. Cloud, the SmartHomeShop app and online firmware manifests do not work in this variant.
• No fallback hotspot. WiFi provisioning (Improv, captive portal) does not exist in the Thread firmware. If the device cannot join your Thread network, reflash or fix the dataset over USB.
• Updates go through the ESPHome Device Builder. OTA over Thread works but is noticeably slower than WiFi, so be patient or update over USB.

Step 1: Copy Your Thread Dataset

1. In Home Assistant go to Settings → Devices & Services → Thread.
2. Click Configure (cogwheel).
3. Click the information icon next to your preferred network.
4. Copy the Active dataset TLVs string. This is what the sensor needs to join your network.

Step 2: Create the Device in the ESPHome Device Builder

1. Open the ESPHome Device Builder and choose New device.
2. Give it a name and skip the installation step for now.
3. Open Edit on the new device and replace the YAML with:

substitutions:
  thread_dataset: "PASTE_YOUR_ACTIVE_DATASET_TLVS_HERE"

packages:
  remote_package:
    url: https://github.com/smarthomeshop/ultimatesensor-mini
    ref: main
    files: [ultimatesensor-mini-v2/ultimatesensor-mini-v2-thread-basic.yaml]
    refresh: 1d

4. Paste your dataset TLVs from step 1 into thread_dataset.
5. Pick the file that matches your hardware:

Step 3: First Installation over USB

1. Connect the Mini v2 with USB-C to the computer on which you have the Device Builder open in Chrome or Edge.
2. Choose Install → Plug into this computer and wait for the build and flash to finish. If the Mini v2 is connected to the machine that runs the Device Builder, choose Plug into the computer running ESPHome Device Builder.
3. After booting, the device joins your Thread network. In the logs you should see OpenThread come up and an IPv6 address appear.

Step 4: Add It to Home Assistant

The device announces itself like any other ESPHome device. Home Assistant discovers it automatically (Settings → Devices & Services → ESPHome). All sensors work exactly like on the WiFi firmware.

Switching Back to WiFi or Ethernet

Flash the matching WiFi or Ethernet variant over USB. The web flasher returns the device to its factory settings, so note your Temperature Offset and Humidity Offset values first: they are stored on the device.

Troubleshooting