Matter Thermostat not showing Fan Entity

Hardware
1

Howdy, not sure if anyone has seen this, but I just installed my new Matter Thermostat (Meross MTS300) and there seems to be no fan entity?

Is this a limitation of Home Assistant or the device?

2

Anyone have a clue or know if there’s a way to check if the device exposes a fan entity?

3

I’m not sure about your Matter thermostat because I don’t have one, but I do have a Z-Wave thermostat with the exact same situation. Generally speaking, this is a limitation of the device, as it does not “publish” a fan endpoint that HA can discover.

If you go to Developer Tools and then States, expand the “Set State” dropdown and find your climate.matter_thermostat entity. If (like mine) you have attributes for fan_mode and fan_modes then you can try creating a template fan entity to control the fan by setting the mode to one of the options in the “modes” list; if you do not have these attributes you may be out of luck. Mine looks like this:

fan:
  - platform: template
    fans:
      # make an on/off fan using thermostat fan control
      hvac_blower_fan:
        friendly_name: "HVAC Blower Fan"
        value_template: "{{ is_state_attr('climate.zwave_thermostat', 'fan_mode', 'Low') }}"
        turn_on:
          service: climate.set_fan_mode
          data:
            fan_mode: 'Low'
            entity_id: climate.zwave_thermostat
        turn_off:
          service: climate.set_fan_mode
          data:
            fan_mode: 'Auto low' 
            entity_id: climate.zwave_thermostat
4

It’s probably some artifical limitation from the device (software). :-1:

The real problem actually seems to be the matter specification which does not mandate to make all actors/sensors/etc. available via matter. :put_litter_in_its_place:

Vendors are allowed to build walled gardens around their matter certified products that may even require hubs or cloud (other people computers) accounts for full control :person_facepalming:

5

I appreciate the additional insight, unfortunately no such luck seeing a fan :cry:

6

I can also confirm that there are only basic controls available in HomeAssistant for the MTS300. I need to be able to control the Fan and Aux modes, and currently the firmware does not support this. Also, be aware that if you do not have Google Home, HomeKit, or SmartThings, that it does not seem possible to get the App to work. I had to do the initial install with the Meross app, and then switch over to HA for the matter pairing. after which the app didn’t see the thermostat (and HA could only control basic settings). This would probably be easier fi you already have a matter ecosystem.