Xiaomi Air Parifier 4 Pro Review

Product specifications

• Model: Xiaomi Smart Air Purifier 4 Pro;
• Main color: white;
• Recommended maintenance area: 60 m²;
• Power consumption: 50 W;
• Power supply voltage: 100-240V / 50Hz;
• Maximum air exchange: 500 m³/h;
• Charcoal filter: yes;
• Prefilter: yes;
• HEPA – filter: yes;
• Ionization: yes;
• Ozonation: no;
• Fragrance: none;
• Control: manual;
• Remote control: no;
• Air purity control: yes;
• Smartphone control: Wi-Fi;
• Control application: Mi Home;
• Voice Assistant: Google, Alexa;
• Display: yes;
• Power on/work indicator: yes;
• Filter pollution indicator: yes;
• Maximum noise level: 64 dB;
• Width: 275 mm;
• Height: 680 mm;
• Depth: 275 mm;
• Weight: 6.8 kg.

Package and appearance of the device

• The body of the air purifier is made of matte white plastic.
• Functionally, the case is divided into two parts: lower and upper. The lower (perforated) part is used to take in and filter the incoming air. In the upper part there is an electric motor and all the electronic filling of the cleaner.
• The front panel has a window for the information display, as well as the purifier controls.
• On the back of the case are temperature and humidity sensors, a button to turn the display on and off, and a laser air quality sensor hidden behind a small grille.
• On the back of the case, in the lower part, there is a filter compartment covered with a plastic perforated cover.
• There are four magnets around the edges of the lid to keep the lid securely in place. At the top end of the lid there is another, small, magnet. This magnet is used to control the closing of the filter compartment.
• At the upper end of the case there is a ventilation duct covered with a decorative plastic grille. To clean the fan and air duct, this cover can be removed by loosening the fixing screw.

Structure:

• Inside the ventilation duct, there are two small contacts used to ionize the air.
• There are four rubberized feet and a connector for connecting the power cable at the bottom of the case.
• A filter is supplied with the purifier, power cable and user manual.

More interesting:

• The filter consists of three parts: outer fine metal mesh (prefilter), central HEPA filter (Xiaomi high-efficiency filter), inner activated carbon filter.
• An RFID tag with information about the filter is pasted on the bottom end of the filter.
• The power cable is one and a half meters long.
• The User's Guide consists of six sheets.

Controls and indications

Information about the operation of the cleaner is displayed on a small display. Below the display are two touch control buttons: a power button and a button for switching operating modes.

While the purifier is running, the display shows the following information:

• The PM2.5 value is the level of fine (PM2.5) particles in the air.
• Temperature – room temperature in degrees Celsius.
• Humidity – relative humidity in %.
• Negative ion indicator – The purifier may generate negative ions during operation. If the indicator is on, the ionization function is on.
• Wi-Fi network indicator – displays the status of the Wi-Fi network (the indicator is on – the network is connected).
• Operating mode – displaying the current operating mode of the purifier. The purifier can operate in one of six modes: automatic (the rate of clean air is adjusted according to the current air quality in the room). Sleep (ultra-low noise for a comfortable acoustic environment for sleeping), low speed, medium speed, high speed, manual, clean airflow rate adjusted by user (via Mi Home app).
• Large Particle Indicator – The level of large (PM2.5-PM10) particles in the air. Depending on the number of particles in the air, the indicator displays one of four values: the scale is a quarter full (minimum pollution), the scale is half full (light pollution), the scale is 75% full (medium pollution), the scale is full (heavy pollution).

Software

• To control and configure the purifier, you need to install the Mi Home app on your smartphone. The application is available for download in the App Store and Google Play.
• After installing the application and registering, the device tab opens in it, which displays all added devices.
• Adding a device is done through a series of simple and intuitive steps. In order for your device to be automatically detected by your smartphone, Bluetooth, Wi-Fi, and location must be enabled on your smartphone.
• After adding a device to the application, it will display information about the operation, and the user will be able to remotely control: turn the device on and off, change the operating mode, turn on air ionization, control the display brightness and notification sound, enable control button lock (child lock).
• In the application, you can set the schedule for the device.
• It is possible to create smart scripts (control scripts). The script specifies an input condition (if) and a reaction to it (then).
• The input condition can be time, a device sensor, a separate sensor, or a sensor in another device. The response to the input condition can be turning the device on or off, changing its mode of operation.
• Moreover, the application allows you to update the device software version.
• In the application, you can assemble several devices by synchronizing their joint work (smart home system).

In addition to being controlled by a smartphone, devices can also be launched by voice commands using Google Assistant or Amazon Alexa.

Testing

The air purifier was tested in two stages:

• Launch in various modes with the measurement of the clean air supply rate and the measurement of the noise level during operation.
• Test the performance of the purifier by running it indoors and measuring it with an air quality monitor.
• The flow rate of purified air was measured using a CEM DT-618 hot-wire anemometer.
• To measure the noise level during operation, a CEM DT-805 sound level meter was used.
• Air quality readings were taken using an Espada M3 air quality monitor.

Sleep Mode

1. In sleep mode, the air purifier operates at minimum power and makes little noise.
2. The speed of air movement supplied by the purifier in this mode is 0.5 m/s.
3. The cross-sectional area of ​​the ventilation grill through which purified air is supplied is 0.0342 m².
4. To calculate the air supply rate, we apply the formula: Q = VCP × F × 3600 [m³/h], where VCP [m/s] – average flow velocity, F [m²] – cross-sectional area in the measured area.
5. After substituting the obtained values ​​into the formula, we obtain the purified air supply rate equal to 61.56 m³ / h.
6. The noise level from the operation of the air purifier was 41 dB.

Mode low speed

1. In this mode, air is supplied at a low speed.
2. The air velocity supplied by the purifier in this mode is 1.6 m/s.
3. After substituting the obtained values ​​into the formula given earlier, we obtain the purified air supply rate equal to 196.99 m³/h.
4. The noise level from the operation of the air purifier was 47 dB.

Medium speed mode

1. In this mode, clean air is supplied at medium speed.
2. The air velocity supplied by the purifier in this mode is 2.1 m/s.
3. After substituting the obtained values ​​into the formula given earlier, we obtain the purified air supply rate equal to 258.55 m³ / h.
4. The noise level from the operation of the air purifier was 53.6 dB.

High-speed mode

1. In this mode, clean air is supplied at a high speed.
2. The speed of air movement supplied by the purifier in this mode is 3 m/s.
3. After substituting the obtained values ​​into the formula given earlier, we get the purified air supply rate equal to 369.36 m³/h.
4. The noise level from the operation of the air purifier was 61.1 dB.

Manual mode

1. In this mode, the clean airflow rate is set in the application, by setting the area of ​​the room to be cleaned.
2. Measurements were made for rooms with an area of ​​​​20-34 m² and 35-60 m² (maximum performance).
3. In the first case, the air velocity supplied by the purifier was 1.7 m/s. Purified air supply rate – 209.3 m³/h. The noise level from the operation of the air purifier is 48 dB.
4. In the second case, the air velocity supplied by the purifier was 3.8 m/s. Purified air supply rate – 467.86 m³/h. The noise level from the operation of the air purifier is 67.4 dB.
5. Evaluate the performance of the purifier in real conditions.
6. To evaluate the performance of the purifier in real conditions, it was installed in the center of a 16.78 m² room with a ceiling height of 2.43 m. An Espada M3 air quality monitor was installed at the farthest point (on the window) from the purifier.
7. The purifier worked in manual mode with room area settings of 35-60 m² (maximum performance).
8. Indoor air quality was assessed using the Xiaomi Smart Air Purifier 4 Pro air quality measurement sensor and the Espada M3 air quality monitor.
9. Initial dаta: PM2.5 – 52, PM10 – 63.

Child Lock

Press and hold the mode button for 7 seconds to enable the child lock function. Thereafter, the purifier will emit a beep and display the “lock” icon on the display. The control buttons on the front panel will stop working. You can also activate this feature in the Mi Home app.

Set display brightness: By pressing the display on/off button, you can change the brightness of the display between three levels: bright, dim, off.

Protection against working with an open filter compartment: If the filter compartment cover is open, the air purifier will not work. And the corresponding icon will be displayed on the display.

Summary

The Xiaomi Smart Air Purifier 4 Pro does an excellent job of cleaning the air of pet hair, dust, and odors in a 61 m² apartment. Breathing in the apartment has become much easier, and the quality of sleep has improved. Summary:

Dignity

• Stylish appearance;
• Multi-stage air filter;
• The presence of an air ionization function;
• The ability to work as part of a smart home system;
• Remote control via smartphone;
• High capacity (500 m³/h);
• Six operating modes.

Disadvantages

• High cost of the device and consumables (filter).