Ambi Climate will automatically update to the latest firmware as long as it is plugged in and has access to stable WiFi connection.
You may notice that your Ambi Climate's LED sometimes dim and become unresponsive. This is likely due to a firmware update. Let the device sit for a couple hours, the firmware update should be completed within this time frame. You can check your firmware version under Device Settings>Device Check>Firmware. (Firmware v340 will accept special characters during setup).
See here for the latest firmware versions.