Managing Devices That Change IDs

Many battery-powered sensors pick a new random transmitter ID every time their batteries are changed. rtl_433 identifies a device by that ID, so the sensor comes back as a brand-new device with new entities and no history, while the original stops updating and eventually goes unavailable.

rtl_433 can't tell the difference between a new device and one that changed its ID. To re-link the device, go to the Add or replace device page.

Find the new device's card and click Replace, then pick the device it replaces. Devices of the same model are listed first, since a battery swap does not change the model. The button only appears once there is at least one added device the candidate could stand in for.

The device is updated to take over the new ID. Entity IDs do not change even if they contain the old ID. Automations, history, dashboards, and so on will all keep working as they did before.

To confirm you are picking the right device, check the Serial number on the device info card: it is the ID rtl_433 decoded for that device, plus its channel and subtype when it has them. Unlike the device name, the serial number is not affected by renaming the device, so it always shows the transmitter the device is currently tracking — the old ID before a replace, the new one after.