Xiaomi Contactless Thermometer: Full Instructions for Setup and Calibration

Xiaomi’s contactless thermometers (such as the Mi Thermometer 2, Xiaomi Smart Thermometer or Mijia iHealth Thermometer) have become an integral part of the home medicine cabinet, especially after 2020. These devices combine the accuracy of the infrared sensor with the convenience of synchronizing with a smartphone via Mi Home or Zepp Life. However, many users face problems when first set up: the device does not connect to the phone, shows the wrong temperature or suddenly shuts down.

In this article, you will find step-by-step instructions for setting up Xiaomi’s contactless thermometer, from unpacking to fine calibration. We will learn how to properly sync the device with the application, update the firmware, reset to factory settings and fix typical errors.

If your thermometer is already lying idle because of a connection error or if it's showing false values, don't throw it away. 90 percent of the time, it's solved by simply flashing it or resetting it, and for those who are just planning to buy, we've compiled a comparison table of the models with their key features.

1.Preparation for the first setup: what to do before turning on

Before you start setting up, make sure you have everything you need. Xiaomi’s contactless thermometers require minimal preparation, but skipping even one step can cause crashes.

First, check the package. The box should have:

• 📦 Thermometer with infrared sensor
• 🔋 Two batteries like this. AAA (In some models, a built-in battery)
• 📄 Short instructions in Chinese/English
• 🔗 USB-Type-C cable (if the model supports charging)

Mi Thermometer 2

Mijia iHealth

Type-C

Xiaomi Smart Thermometer Pro

Second, install the necessary software:

• 📱 Mi Home (for most models) or Zepp Life (for iHealth thermometers)
• 🔄 Update the app to the latest version – older versions do not support new devices
• 🌐 Connect your phone to a 2.4GHz Wi-Fi network (thermometers do not work with 5GHz)

If you are using an iPhone, make sure that the privacy settings are in place. → Bluetooth is allowed for Mi Home. On Android, check location permissions and Bluetooth – without them, you can’t connect.

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Before first turning on, wipe the infrared thermometer sensor with an alcohol napkin. Dust or greasy traces can distort the readings.

2. Step-by-step instructions: how to connect the thermometer to Mi Home

The connection process takes no more than 5 minutes, if you follow the algorithm, and we'll look at two scenarios: battery thermometers and built-in battery.

For battery-powered models (Mi Thermometer 2, Mijia iHealth):

For battery models (Xiaomi Smart Thermometer Pro):

1. In Mi Home, select Add Device → Bluetooth.

If the thermometer is not present, try:

• 🔄 Reboot Bluetooth on your phone
• 📵 Shut down. VPN Proxies (they block the connection to Xiaomi servers)
• 🔋 Replace batteries (even if they are new – factory marriage is possible)

The latest update to Mi Home has been installed|Phone connected to 2.4 GHz Wi-Fi|Bluetooth is enabled and visible to other devices|Batteries are inserted correctly (plus plus)|The thermometer is within 1 meter radius of the phone-->

Calibration of the thermometer: how to check and adjust the accuracy

Even Xiaomi factory thermometers can give an error ±0.3°C. To minimize the error, calibrate. To do this, you will need a reference thermometer (e.g., mercury or electronic with proven accuracy).

Step 1: Test on a stable surface

Step 2: Set up the Mi Home Amendment

1. Open the app, find your thermometer in the list of devices.
2. Go to Settings. → Calibration of temperature.
3. Enter the value of the correction (for example, if Xiaomi shows 19.7).°C, and the standard is 20.0.°C, enter +0.3).
4. Save the settings and repeat the test.

Step 3: Human testing

• 👶 Measure the temperature of the forehead of a healthy person with a reference thermometer (for example, in the axillary cavity).
• 🔍 Point Xiaomi on the forehead from a distance of 1-3 cm, holding the button 2-3 seconds.
• ⚠️ The normal difference between armpit and frontal temperature is 0.5–1.0°C (forehead always colder).

4. Firmware Update: Why It Matters and How to Do It

Thermometer firmware is responsible for measuring accuracy, stable communication with the phone and support for new features. Mi Thermometer 2 and later require firmware updates at least 1 time every 6 months - otherwise, there may be failures when synchronizing with Mi Home.

How to check the firmware version:

1. Open your Mi Home, select your thermometer.
2. Go to Settings. → About the device.
3. Find the firmware version line (for example, 1.2.4_0018).

How to update firmware:

• 🔄 If an update is available, you will see a notification in the app. click Update.
• 📶 Make sure your phone is connected to stable Wi-Fi (non-mobile internet!).
• ⏳ Don't interrupt the process - it takes 2-5 minutes. The thermometer will flash blue during the update.
• 🔋 If the update is hanging, remove the batteries for 10 seconds and try again.

What to do if the update is not available?

• 🌍 Check out the region in Mi Home: Choose Mainland China – updates are coming sooner.
• 📱 Remove and reinstall the app – sometimes the cache blocks the search for updates.
• 🔌 Connect the thermometer to another phone (for example, on Android 10)+ iOS).

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After updating the firmware, reset the temperature calibration – new versions of the software can change the measurement algorithms.

5. Synchronization with other devices: smart home and third-party applications

Xiaomi’s contactless thermometers can be integrated not only with the Mi Home, but also with other ecosystems, allowing for automated alerts (e.g., sending out alerts). SMS at high temperature in a child) or display data on a smart watch.

Synchronization options:

How to connect to Home Assistant:

1. Make sure that the Xiaomi component is installed on the server BLE.
2. Add to configuration.yaml: sensor: - platform: mitemp_bt mac: 'XX:XX:XX:XX:XX:XX' # MAC-Thermometer address: "Xiaomi Thermometer" force_update: true median: 3
3. Reboot Home Assistant and check the log for errors.

Notification automation (example for Mi Home):

• Open Profile → Automation → Create.
• Select the condition: Temperature > 37.5°C.
• Add the action: Send a notification to your phone or turn on the smart lamp.

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For stable work with Home Assistant, turn off power saving for Bluetooth on your phone (in battery settings).

Typical errors and their elimination

Even when set up correctly, Xiaomi thermometers can produce errors, and we've collected some of the most common problems and solutions.

Error: "Device disabled" in Mi Home

• 🔋 Check the batteries – replace them with new ones (even if the indicator shows a charge).
• 📵 Reconnect the thermometer: Remove it from the app and add it again.
• 🔄 Reboot your phone and router (sometimes conflicting) IP-address).

Error: "Incorrect temperature value" (shows 0.0)°C or 99.9°C)

• 🧹 Clean the dust sensor with an alcohol tampon.
• 🔄 Reset the calibration in the application settings.
• 🔋 Remove the batteries for 1 minute, then insert back in.

Mistake: Thermometer is not synchronized with phone

⚠️ Warning: If the thermometer is plugged in but the data is not updated, check Mi Home's permissions for background activity (on Android: Settings) → Annexes → Mi Home → Battery → No restrictions).

• 📱 Remove the Mi Home app cache.
• 🔄 Switch from 5GHz Wi-Fi to 2.4GHz.
• 🔌 Try connecting from another phone (possibly a problem in your device’s Bluetooth module).

Error: After updating the firmware thermometer does not turn on

⚠️ Warning: If the thermometer does not respond to the button after a failed update, perform a hardware reset: press the power button for 15 seconds (up to a double beep). If this does not help, contact the service (possibly damaged device memory).

7. Reset to factory settings: when and how to do

Reset is required in three cases:

1. You sell or transfer the thermometer to another user.
2. The device is unstable (frequent errors, freezes).
3. You want to reconnect the thermometer to another Mi Home account.

How to reset your settings:

1. Remove the batteries (if the model is on the battery - discharge it before turning it off).
2. Press the power button for 10-15 seconds (double signal should sound).
3. Put the batteries back in, the thermometer will return to factory settings.

How to remove the thermometer from Mi Home before resetting:

1. Open the app, find the device in the list.
2. Click on three dots in the upper right corner → Remove the device.
3. Confirm the deletion (measurement data will be lost!).

What to do if the reset does not help?

• 🔌 Try connecting the thermometer to another phone with a clean Mi Home installation.
• 🔋 If the model is on the battery - connect to charging for 1 hour, then repeat the reset.
• 📧 Contact Xiaomi Support (attach video problems to speed up response).

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Once reset, the thermometer will lose its entire measurement history. If the data is important, export it to the next level. PDF via Zepp Life before resetting.

FAQ: Frequent questions about Xiaomi contactless thermometers