# Serin Controller Matter setup

> Connect a Mitsubishi mini-split to Google Home, Alexa or SmartThings with Serin Controller and Matter-compatible firmware. Pair the thermostat in your app.

Source: https://serin-labs.com/matter/setup.html
Last updated: 2026-10-27

Add your controller to Google Home, Alexa or SmartThings using **Matter-compatible firmware**. The app supplies Wi-Fi credentials during pairing; a fresh installation has no separate setup-hotspot step.

Different firmware? [Choose your guide](https://serin-labs.com/controller/firmware.html).

**Continue an existing setup**

- **Not installed in the indoor unit yet?** Install it in the indoor unit.
- **Ready to add it to your app?** Add your controller to your app.
- **Already paired and installed?** Check that the unit responds.

## Before you start

- A compatible indoor unit and controller with **this guide's firmware installed**. If you have not flashed it yet, use the [flash tool](https://serin-labs.com/flash.html?platform=direct) on a computer with a USB-C data cable.
- A 2.4 GHz home Wi-Fi network and its password.
- Your smart-home app and a compatible hub. Check the requirements in your app's section below.
- IPv6 enabled on your home network, and your phone near the controller for pairing over Bluetooth.

Note

**Uncertified accessory.** This firmware is not Matter-certified. Your app may require confirmation when pairing.

## 1 Install the controller

Warning

**Power off at the breaker.** Leave it off while the unit is open. Disconnect USB before connecting CN105.

Follow the [installation guide](https://serin-labs.com/controller/install.html) to connect the CN105 cable, position the controller, and replace the cover before restoring power.

## 2 Add the Matter thermostat

**Already paired in your app?** Check control.

1. Stand near the controller with your phone. Begin adding a device in your app.
2. Scan the Matter QR code or enter its 11-digit pairing code. The flash tool displays it after installation and saves it in the same browser. The controller also prints it to the serial console at startup.
3. Follow the app's prompts to supply your 2.4 GHz Wi-Fi network. The credentials transfer over Bluetooth. Confirm any uncertified-accessory notice.
4. Assign the thermostat to its room. Once added, the hub controls the controller over the local network.

Tip

**Missing your pairing code?** If this browser has no saved code, return to the [flash tool](https://serin-labs.com/flash.html) on the computer used to install the firmware, or read the code from the controller [over USB](https://serin-labs.com/controller/recovery.html#reset). A missing saved record does not mean you must erase or reflash the controller.

### Google Home

Requires the Google Home app and a [compatible Google or Nest hub](https://support.google.com/googlehome/answer/12391458?hl=en).

### Amazon Alexa

Requires the Alexa app and a [supported Echo or eero device](https://developer.amazon.com/en-US/docs/alexa/smarthome/matter-support.html). No custom Alexa skill is required.

### SmartThings

Requires the SmartThings app and a [compatible Matter hub](https://support.smartthings.com/hc/en-us/articles/11219700390804-SmartThings-x-Matter-Integration).

Apple Home and Home Assistant can also add this firmware through Matter. Use its Matter code, not a HomeKit setup code. To add another app to an already paired controller, follow [Matter multi-admin pairing](https://serin-labs.com/controller/pairing.html#pairing).

For pairing timeouts, a missing code, or an unavailable thermostat, see [Matter troubleshooting](https://serin-labs.com/troubleshooting.html#matter).

## 3 Check that the unit responds

1. Check that the app reports the room temperature.
2. Change the mode or target temperature and confirm the indoor unit responds.

If the app connects but commands have no effect, use [the CN105 checks](https://serin-labs.com/troubleshooting.html#hvac-no-response). App pairing does not verify the cable's data connection.

For another indoor unit, repeat setup with its own controller and a unique name. Continue with [use and configuration](https://serin-labs.com/controller/manual.html#use).