serin labsFollow these steps for a new controller. If you have already installed firmware or joined Wi-Fi at the bench, continue from the first unfinished step.
1 Check compatibility and gather what you need
Check your indoor-unit model and confirm its CN105 port is available.
- Hardware: one controller and CN105 cable per indoor unit, plus a USB-C data cable for flashing.
- Computer: Chrome, Edge or Brave for the browser flash tool.
- Smart home: your app and any required hub or Home Assistant installation. Check the platform guide for requirements.
The Serin Controller is assembled and ready for you to flash. Building your own? Use the supported boards and parts list.
2 Choose and install firmware
Choose the firmware for your smart-home app, then use the browser flash tool. Flash with the controller disconnected from CN105 and powered only by USB. The tool can also help with Wi-Fi and show pairing codes.
Already flashed? Keep the firmware you want and continue to installation. Routine updates do not require repeating first-time setup.
3 Install the controller in the indoor unit
Follow the installation guide to connect CN105, position the controller, replace the cover, and restore power.
4 Finish setup in your app
Choose the guide for the firmware you installed. These instructions also work on your phone. Skip Wi-Fi or pairing steps you already completed in the flash tool.
5 Check that control works
Send a mode or target-temperature change from the app and confirm the indoor unit responds. Check that a current temperature is reported. If the app connects but the indoor unit does not respond, use the CN105 troubleshooting steps.
Setup is complete when the app reports the room temperature and your indoor unit responds to a command.
For multiple indoor units, repeat setup for each controller and give each a distinct room name. Then explore web controls, room sensors, and maintenance.