Pairing Mysa Baseboard 3 with Amazon Alexa via Matter

Last updated: August 14, 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

This guide covers pairing your Mysa Baseboard 3 thermostat to Amazon Alexa using Matter, what you can do once it is paired, Alexa voice commands, and Alexa-specific limitations. For an overview of Matter and links to other Baseboard 3 Matter guides, see Mysa Baseboard 3: Connecting to your Smart Home using Matter.

Before You Start

Your thermostat, the phone running the Mysa app, and your Alexa hub must all be on the same Wi-Fi network. If any are on a different or guest network, pairing may fail or the thermostat may appear unresponsive.

  • Mysa Smart Thermostat for Electric Baseboard Heaters V3 / Baseboard 3 with the required Baseboard 3 firmware version, online in the Mysa app.

  • Mysa app (iOS or Android) 4.18 or later, signed in.

  • The Alexa app on an iPhone or Android phone.

  • A Matter-compatible Alexa hub — most current Echo speakers, Echo Show displays, and eero routers support Matter. Older Echo (1st/2nd gen) and Echo Dot (3rd gen and earlier) do not.

Step 1 — Make Sure Baseboard 3 Setup Is Complete

  1. Install and complete setup for your Baseboard 3 in the Mysa app.

  2. Open the Mysa app and make sure your Baseboard 3 is online and connected.

  3. Confirm the Matter QR code is available for your thermostat after setup is complete.

Important: For Baseboard 3, the Matter QR code is ready only after Mysa app setup is complete.

Step 2 — Add the Thermostat in Alexa

  1. Open the Alexa app and tap Devices.

  2. Tap the + button and choose Add Device.

  3. Scroll down and select Other, then choose Matter.

  4. Tap Yes on the “Does your device have a Matter logo?” question.

  5. Scan the Matter QR code for your Baseboard 3, or tap Enter setup code to enter the code manually if available.

  6. Tap Connect to start connecting to the device.

  7. Follow the Alexa pairing flow and set up the thermostat when prompted.

  8. Rename the thermostat and add it to a room for voice control.

What You Can Do in Alexa

Feature

Available

Notes

View current temperature

Yes

Shown on the device tile

Adjust heat setpoint

Yes

Baseboard 3 supports temperature control through Matter

Heat / Off mode

Yes

Baseboard 3 is heat-only

Cool / Auto mode

No

Cooling modes do not apply to Baseboard 3

AUX Heat / Fan Only

No

These HVAC modes do not apply to Baseboard 3

Alexa voice control

Yes

Use supported temperature and Heat/Off commands

Routines

Yes

Platform behaviour may vary

Alexa Voice Commands

  • "Alexa, set the [device name] to 22 degrees."

  • "Alexa, what is the temperature on the [device name]?"

  • "Alexa, set the [device name] to heat."

  • "Alexa, turn off the [device name]."

Alexa Limitations

These come from the Matter standard and Amazon's implementation, not from a defect in your thermostat.

Baseboard 3 Is Heat-Only

Baseboard 3 supports Heat and Off through Matter. If Alexa displays other modes, do not use them; unsupported mode commands should not be used.

Voice Command to Turn Off Heat May Vary

If Alexa does not support a “turn off heat” command for your device, use “Alexa, turn off the [device name]” or change the mode to Off in the Alexa app instead.

May Show Unresponsive Before Mysa App Shows Offline

After a Wi-Fi drop, Alexa may flag the thermostat as unresponsive before the Mysa app shows it offline. This is normal.

Setpoint Increments

In the Alexa app, setpoints may be limited to whole-degree increments. If you need a more precise setpoint, set it in the Mysa app.

Re-Pairing After a Reset

Remove the thermostat from Alexa before re-pairing. Then pair again using the Matter setup flow for Baseboard 3.