Temperature Fields on Matter Devices do not convert to User Preferences

[Omnipius]

For any Matter device that shows a temperature (sensor, thermostat, etc), the Google Home app and Assistant/Gemini only displays, reads out, and accepts values in Celsius, regardless of the user's temperature unit preferences. While it is true that all communication (Matter or otherwise) should be done in Celsius, the units displayed in the app, read out by Assistant/Gemini, or used in commands and/or automations should be assumed to match the user's temperature unit preference unless the user specifies otherwise** for a given device or command. This appears to have been an oversight in the development of Matter support or a bug in temperature unit implementation

** This means that all Matter device application clusters that represent physical temperature should have an in-app setting for temperature unit [C, F, or Auto (default)]

[Suc_dpe · Accepted solution]

Hello,

Thanks for reporting this temperature unit conversion issue with Matter devices. You're right that Google Home should respect user temperature preferences when displaying and interpreting values from Matter devices.

This is a valuable insight. Please file a bug in Google's Issue Tracker  and post the bug ID back here so I can escalate it to the appropriate team.

[Omnipius]

Issue created: https://issuetracker.google.com/451750204 

[WhatstheMatter2]

Same issue! Same devices (Thermostat and ESPHome) now connected via Matter to SmartHome Hub instead of Google's Cloud API are now displaying all temperature measurements exclusively in Celsius in the Google Home app. Gemini is configured with Fahrenheit preference, but continues to read these devices as Celsius. Matter bridge logs show unit-less measurements in values associated with Fahrenheit (i.e. current_temp 67, temperature 100, temp_min 50, temp_max 100). Hub and thermostat are both configured in Fahrenheit. The end result is Gemini/Google Assistant set the thermostat temperature to the thermostat max (100) instead of the requested 70 degrees. My assumption is that Google attempted to set the thermostat to 70 C (which is 158 F). Please fix this bug!

[WhatMatters]

Also experiencing the same issue with multiple temperature sensors both matter and Wi-Fi. The home app simply does not recognize the user preference displays all temperature settings in Celsius. 

[WhatstheMatter2]

Considering adding your voice or +1 to the original 2023 Issue Tracker here and a new Issue Tracker here to communicate shared support! Let's get this bug fixed.