Using Matter with Multiple Smart Home Platforms for Baseboard 3

Last updated: October 5, 2026

Product: Mysa Smart Thermostat for Electric Baseboard Heaters V3 / Baseboard 3 | Firmware: 5.1.4 or later | App: Mysa app 4.18 or later

Matter supports multi-admin — the ability to connect your Baseboard 3 thermostat to Apple Home, Google Home, and Alexa at the same time. You can control the heat setpoint and switch between Heat and Off from whichever app or voice assistant you prefer, and changes sync with the Mysa app.

For pairing your first platform, see Mysa Baseboard 3: Connecting to your Smart Home using Matter and the Baseboard 3 platform-specific guides.

The Most Important Thing to Understand

The Matter QR code or setup code used for initial setup can only be used to pair to one platform. Once used, that code is consumed. To add your thermostat to a second or third platform, generate a new sharing code from the platform you already paired to.

Example:

You paired Baseboard 3 to Apple Home first. To also add it to Google Home, open Apple Home, find your thermostat's settings, and turn on pairing mode to generate a new one-time sharing code. Use that code in Google Home.

Note: Sharing codes from multi-admin support expire after 15 minutes. Have your second platform app open and ready before you generate the code. If it expires, generate another from the first platform.

How to Generate a Sharing Code from Each Platform

From Apple Home

  • Open the Home app and tap your thermostat tile.

  • Tap the gear icon (Settings).

  • Scroll down and tap Turn On Pairing Mode.

  • When “Accessory Ready to Connect” appears, tap Copy Code.

  • Switch to your second platform app and enter the code when prompted.

From Google Home

  • Open Google Home and tap and hold your thermostat tile.

  • Tap the gear icon (Settings).

  • Tap Linked Matter apps & services.

  • Tap Link apps & services → Use pairing code.

  • Tap Copy pairing code.

  • Switch to your second platform app and enter the code when prompted.

From Amazon Alexa

  • Open the Alexa app and go to Devices.

  • Open your Baseboard 3 thermostat device and tap Settings.

  • Look for the Matter sharing or “other assistants and apps” option.

  • Generate and copy the setup code.

  • Switch to your second platform app and enter the code when prompted.

Recommended Pairing Order

There is no strict requirement, but pairing to Apple Home first is a common approach because Apple Home's pairing-mode flow is well documented and generates sharing codes reliably. From there, use a sharing code to add to Google Home, then use Google Home's linked Matter apps flow to add to Alexa.

Note: Scenes, routines, and automations are per-platform. Adding your thermostat to a second platform does not copy your existing scenes — you will set those up separately in each app.

Supported Controls Across Platforms

Baseboard 3 is heat-only. Through Matter, supported controls are temperature control and Heat / Off modes.