Connecting Xiaomi thermometer to Mi Home: full instruction with error solutions

Why Xiaomi Thermometers Need a Special Connection Approach

Xiaomi thermometers and hygrometers have long been an integral part of the smart home ecosystem, but their connection often raises questions even among experienced users. Unlike most of the brand’s gadgets, thermometers (for example, MiJia Bluetooth Thermometer 2 or ClearGrass) TG31) They use unique communication protocols, from classic Bluetooth to proprietary MiBeacon, which requires a precise sequence of actions.

The main problem is the lack of a universal algorithm: 2023 models (like Xiaomi Smart Temperature and Humidity Sensor 2) connect via Mi Home differently than their predecessors in 2020. Besides, after the application update in 2026, the configuration interface has changed, and the old manuals are outdated. This article is relevant to the latest versions of the software and takes into account all the nuances from choosing a region in Mi Home to solving the error "Device not found".

Before you start, check three key points: 1 – your thermometer supports connecting to Mi Home (the list of compatible models below), 2 – Bluetooth 5.0 is enabled on your smartphone.+ (mandatory for stable operation), 3 - Mi Home app updated to version 6.5.400 or later (check in Settings → About the programme).

List of compatible Xiaomi thermometer models (2020–2026)

Not all the brand thermometers work with Mi Home – some (e.g. Yeelight Thermometer) require a separate Yeelight app. Below is a table of current models that can be connected through the main software ecosystem.

If your model is not listed, check its device code (indicated on the box or under the battery compartment). MHO-C401 They are Mijia series and connect according to the standard scheme, and devices with the prefix Aqara require an additional hub.

⚠️ Xiaomi Mi Temperature and Humidity Sensor 1 (LYWSDCGQ) Mi Homes are not officially supported since 2022, and will require third-party software like Home Assistant or Custom Firmware to connect them.

Step-by-step: connecting thermometer to Mi Home

The synchronization process takes no more than 5 minutes if you follow the exact sequence, below is a universal algorithm for Bluetooth models (for Zigbee devices, you need a separate instruction with a gateway).

Install the latest version of Mi Home (App) Store/Google Play)

Enable Bluetooth and geolocation on your smartphone

Remove the protective film from the thermometer battery

Locate the device at a distance of no more than 1 meter from the phone-->

1. Step 1. Launch Mi Home and select region. Open the app and click Profile → Settings → Region. Select China (even if you're in Europe!) to increase your chances of connecting successfully. ClearGrass models can leave Russia, but then you'll have to manually update your firmware.
2. Step 2. Add a new device. Press + → Add the device → Permissions (geolocation and Bluetooth required!) Type the model name (e.g., "MiJia Thermometer") or select the category "Sensors" in the search box. → Temperature and humidity".
3. Step 3: Sync. When the app finds the thermometer, press "Plug" and wait for the beep from the device. If there's no sound, remove and insert the battery again, then repeat the search.
4. Step 4: Set up location: After connecting, specify a room (e.g., "Children's") and activate the option "Notifications for exceeding thresholds." Recommended values: temperature 18-25°C, humidity 40-60%.

If you have a “failed to connect” error at the synchronization stage, try:

• 🔄 Reboot your smartphone (especially relevant for Android 12 devices)+).
• 📱 Shut down. VPN — It can also block Xiaomi servers.
• 🔋 Replace the battery – even new cells are sometimes discharged.
• 📡 Change the region in the Mi Home settings (from "Europe" to "China" or vice versa).

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If the thermometer is not detected, try connecting it through the Mi Fit app (previously it supported some models of thermometers). Once synchronized, the device will automatically appear in the Mi Home.

Solving common connection errors

Even with the correct following of the instructions, users face problems, and here are some of the most common errors and non-obvious solutions that are not found in the official documentation.

Error 1: "Device not found" (device not found)

Reasons:

• 📵 Bluetooth conflict: the phone turned on the power saving mode, which turns off scanning.
• 🔄 Incompatible firmware: thermometers LYWSD03MMC version 1.2.0_0036 There's a detection bug.
• 📍 Geolocation: Android requires precise location for Bluetooth scanning.

Decisions:

1. Open Android Settings → Annexes → Mi Home → Permits and enable "Exact location".
2. Install alternative firmware, for example ATC MiThermometer (available on GitHub).
3. Try connecting from another phone (preferably on iOS – there are fewer Bluetooth issues).

Error 2: Connection failed (unable to connect)

This error occurs when:

• 🔋 Battery discharged below. 2.8V (even if the thermometer shows a charge).
• 📱 The phone activated "Flight mode" or "Energy saving".
• 🌐 Xiaomi servers are overloaded (check status at status.mi.com).

Critical detail: if the thermometer was previously linked to another Mi Account, it should be reset. for this, 5 times quickly press the button on the side (if any) or remove the battery for 10 minutes.

⚠️ Warning: After 3 failed attempts to connect, Mi Home can lock the device for 24 hours, in which case only changing the account or waiting will help.

Error 3: Data not updated

If the thermometer is connected, but the readings are frozen:

• 📶 Check the distance to the phone/gateway – maximum radius for Bluetooth models is 10 meters (no obstacles).
• ⚙️ In Mi Home, go to Device Settings → Update frequency and select "Every 5 minutes".
• 🔄 Reboot the thermometer: Remove the battery for 30 seconds, then insert back.

Set up notifications and automation

Once successfully connected, the thermometer can be integrated into smart home scenarios, such as setting up the automatic humidifier switch on when humidity drops below 40% or alerting if the nursery temperature rises above 24.°C.

How to set up notifications:

1. Open the device in Mi Home and click "Notifications".
2. Activate the "Attend Excess" switch.
3. Set thresholds (e.g. temperature) >25°C or humidity <30%).
4. Select the notification method: Push notification, SMS (requires a number binding) or a sound signal.

To create automation:

1. Go to Profile. → Automation → Create → If....
2. Select the condition: "Temperature [device] > 24°C".
3. Add the action: "Include [humidifier/air conditioner]".
4. Save the script and activate it.

An example of useful automation for a greenhouse:

• 🌡️ If the temperature > 30°C → fan.
• 💧 If humidity < 50% → irrigate.
• ❄️ If the temperature < 10°C → send out SMS warning.

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For stable operation of automation, the thermometer must always be in the range of a Bluetooth gateway (for example, Xiaomi Gateway) or a smartphone with Mi Home enabled in the background.

How to transfer thermometer to another Mi Account

If you're selling a device or want to transfer it to another user, you need to untie it from your current account, and unlike light bulbs or sockets, thermometers don't have a physical reset button, so it's software-based.

Instructions:

1. Open Mi Home and find your thermometer in the list of devices.
2. Press on "..." → Settings → Untie the device".
3. Confirm the action by entering a password from the Mi Account.
4. Remove the battery for 1 minute – this will reset the cache of the device.

If the "Out" option is inactive:

• 📱 Check that you are logged into the same account to which the thermometer is linked.
• 🔄 Try untie the device via the web version of Mi Home on PC (home.mi.com).
• 📧 Write in support of Xiaomi with the indication Device ID (You can find it in the device settings).

⚠️ Warning: After detachment, all data from the thermometer (history of readings, notification settings) will be deleted without the possibility of recovery.

Xiaomi Thermometer Comparison: Which to Choose in 2026

Xiaomi’s range of thermometers and its sub-brands (Aqara, ClearGrass) includes more than 10 models, and below is a comparison of the most popular options by key parameters.

Selection recommendations:

• 🏠 For the home: ClearGrass TG31 — Optimal due to the display and high accuracy.
• 🌿 For the greenhouse: Aqara + gateway – stable communication over long distances.
• 💰 Budget option: MiJia Bluetooth Thermometer 2 – cheap and reliable.

If you need a thermometer for street use (for example, to control the temperature in the garage), pay attention to models with a high temperature. IP67 (For example, Xiaomi Mijia Outdoor Thermometer. -20°C +60°C.

FAQ: Frequent questions about Xiaomi thermometers