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Comparison Dreame D9 Max vs Roborock S7

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Dreame D9 Max
Roborock S7
Dreame D9 MaxRoborock S7
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Main
Memorization of up to four room maps. Laser cartography. Management with a voice assistant. Vibrating floor cleaning system. Automatic lifting of microfibre upon arrival on the carpet.
Typerobot vacuum cleanerrobot vacuum cleaner
Cleaning typedry and wetdry and wet
Dust collectorcyclone (bagless)cyclone (bagless)
Specs
Suction power40 W
Suction force4000 Pa2500 Pa
Dust collector capacity0.57 L0.47 L
Water tank capacity0.27 L0.3 L
Automatic power control
Fine filterHEPAHEPA 11
Robot vacuum cleaner
Additional operating modes
spot cleaning (Spot)
turbo mode
 
 
turbo mode
vibration mopping
Cleaning area limitappapp
Robot features
scheduled cleaning
anti-fall function
obstacle sensor
water supply control
control via Internet
scheduled cleaning
anti-fall function
obstacle sensor
water supply control
control via Internet
Mapping systemrangefinder (laser)rangefinder (laser)
multi-map memory
Voice assistantAmazon AlexaAmazon Alexa, Google Assistant, Xiaomi AI
Cleaning area250 m²200 m²
Crossing threshold20 mm20 mm
Nozzles included
Nozzle functions
side brush
turbobrush
microfibre
side brush
turbobrush
microfibre
Power source
Source of powerbatterybattery
Battery voltage14.4 V
Battery typeLi-IonLi-Ion
Battery capacity5.2 Ah5.2 Ah
Battery run time150 min180 min
Charging time2 h
Charging station++
More specs
Noise level65 dB58 dB
Dimensions (HxWxD)9.7x35x35 cm9.6x35.35.3 cm
Weight3.8 kg
Added to E-Catalogseptember 2021july 2020

Suction power

The suction power provided by the vacuum cleaner. For models with power adjustment (see below), in this case, the maximum value is taken into account. Note that "suction power" is sometimes erroneously also called the suction force, indicated in pascals; see below for more details.

Suction power is a key indicator that determines the capabilities of the unit: the higher it is, the more efficiently the vacuum cleaner can draw in various contaminants, and the better it handles with carpets, fabrics and other materials into which dust can penetrate deeply. On the other hand, high power inevitably affects the weight, power consumption, dimensions and price of the device. Therefore, it does not always make sense to chase the maximum values — you need to take into account the real working conditions and the general purpose of the vacuum cleaner.

The specific numbers found in this paragraph largely depend on the type of device. For example, in handheld household models, suction power does not exceed 100 W, and for conventional household units, an indicator of 100 – 150 W is still considered very limited. At the same time, we note that the minimum required for a full-fledged dry cleaning of smooth floors is considered to be 300 – 350 W, for carpet and other short pile coatings — 350 – 400 W, and for long pile materials and upholstered furniture higher rates are desirable. Vacuum cleaners with lower suction power values are intended not so much for periodic cleaning, but for constant (ideally daily) maintenance of cleanliness in an already tidy room.

As for the relationship between suction power and suction force, it is as follows: power is the suction force (thrust) multiplied by the airflow (performance). Without going into too much detail, we can say that the efficiency of the vacuum cleaner is determined by both of these indicators. And it is worth evaluating this efficiency by suction power (regardless of the specific relationship between traction and performance).

Suction force

The suction force provided by the vacuum cleaner. It is indicated by the maximum vacuum (negative pressure) that the unit can create at the working nozzle.

Note that this parameter is sometimes confused with the suction power described above, which is indicated in watts. Yes, suction force to some extent determines the efficiency of the unit. However, this efficiency also depends on the performance (airflow). And the suction power, indicated in watts, takes into account both of these parameters — it is determined by multiplying the suction force by the performance (see above for more details). For this reason, there is no strict relationship between this force and suction power: for example, a vacuum of 25,000 Pa can be found in models with 250 W, 200 W and even 150 W of power.

As for the practical significance of this spec, in general, a higher suction force allows you to work more efficiently with high resistance. For example, when processing carpets with a long pile. On the other hand, more pascals (with the same number of watts) means less airflow and, accordingly, less efficiency for large amounts of work at low resistance (for example, cleaning large rooms with parquet floors). Thus, it makes sense to pay attention to this indicator mainly in cases where high suction force is fundamental for you. In other cases, it is worth evaluating the capabilities of the vacuum cleaner in terms of suction power in watts.

Note that for a number of...reasons, the suction power is most often specified for robot vacuum cleaners (see “Produc type”). For such models, a value of 1500 Pa and below is considered very small, 1500 – 2000 Pa — medium, 2000 – 2500 Pa — high, more than 2500 Pa — very high.

It is also worth mentioning that the indication of suction force is often used as a publicity trick — to improve the impression of the product. For example, the suction power of 150 watts in itself is quite modest. But at the same time, the suction force of such a vacuum cleaner can be 25,000 Pa — a very impressive figure, especially for an inexperienced buyer, but having a very indirect relation to real efficiency. Especially often, such tricks are used among upright models and the already mentioned robots — these varieties initially do not differ in high power in watts. For many of these units, the characteristics only indicate the vacuum in pascals without specifying the suction power. It further enhances the impression: for example, in the specs of a modest robot, the figure "3000 Pa" looks much more impressive than "40 W". However, such figures have a very weak relation to the real capabilities of the unit and if they are not supplemented by data on suction power in watts, they should be considered solely as bait for a not particularly sophisticated buyer.

Dust collector capacity

The nominal volume of the dust collector installed in the vacuum cleaner.

This indicator largely depends on the type of unit (see above). For example, in most handheld household models, the capacity does not exceed 0.5 L. The volume of the container in upright vacuum cleaners and robots can be somewhat larger — among the first variety there are quite a few models for 1 – 2 liters or even more, and among the second — by 0.6 – 1 liter and a little more. For conventional vacuum cleaners, the minimum figure is actually about 0.8 – 1 L; dust collectors for 1 – 2 L and 2 – 4 L are very popular in such devices; the maximum capacity is actually 4 – 6 liters — units of a similar layout, but with a larger capacity, are usually referred to as household ones. In turn, relatively small containers are occasionally found among workshop models. However, in vacuum cleaners of this type, the capacity is generally quite large — it can reach 26 – 50 liters or even more ; the same applies to industrial (construction) units.

In general, a larger dust container allows you to work longer without interruptions. On the other hand, a capacious container itself takes up more space and, accordingly, affects the size, weight and price. So when choosing th...is parameter, it is worth considering the actual features of the use of a vacuum cleaner. Here we can give such an example: for a full-scale cleaning of an average city apartment, a capacity of about 1 – 1.5 litres is required. Thus, say, a 4-litre bag allows you to carry out two such cleanings with sufficient efficiency without unloading the vacuum cleaner. There are more detailed recommendations regarding the optimal volume of the dust collector, including specific cleaning options. These recommendations can be found in special sources.

Water tank capacity

A capacity of a tank for water or detergent a vacuum cleaner with a wet cleaning function is equipped with. (see "Cleaning type").

Large capacity allows you to work longer without refilling the tank. On the other hand, an increase in capacity has a corresponding effect on the size, weight and cost of the unit. Thus, manufacturers choose this parameter taking into account the general specialization and the “weight category” of a particular model. So, in robots (see "Type"), the volume of the water tank is, by definition, small. Even in the heaviest models, it does not exceed 650 mL. But other types of vacuum cleaners can differ markedly in this parameter.

In general, for non-robot units, a capacity of 1 liter or less is considered very limited, 1 – 2 liters is small, 2 – 3 liters is average, more than 3 liters is above average. However, it much depends on the type. For example, in conventional vacuum cleaners, the capacity does not exceed 2.5 liters, and "for workshop" models this is very little — in most cases, they have a tank capacity of 3 liters or more.

Fine filter

The presence of a HEPA fine filter in the vacuum cleaner; also in this paragraph, the specific class of this filter is often specified.

HEPA (High Efficiency Particulate Absorbing) filters are designed to purify the air from the smallest mechanical contaminants — up to tenths of a micron in size. It allows you to trap not only fine dust but even bacteria. For comparison: the size of most bacteria starts at 0.5 microns, and the effectiveness of HEPA filters is evaluated by the ability to retain particles with a size of 0.1 – 0.3 microns. The most advanced such filters ( class 13 and above) are able to remove more than 99.9% of these particles from the air. Here is a more detailed description of the different classes:

— HEPA 10 – traps at least 85% of particles with a size of 0.1 – 0.3 microns;
— HEPA 11 – at least 95% of such particles;
— HEPA 12 – not less than 99.5%;
— HEPA 13 – not less than 99.95%;
— HEPA 14 – not less than 99.995%;

Note that pollution with a size of 0.1 – 0.3 microns is the worst-kept by HEPA filters, so with particles of other sizes (both larger and smaller), the efficiency of such elements will be even higher.

Regarding the choice for this parameter, it is worth noting that, in fact, it does not always make sense to pursue a high filtration class. For example, during wet cleaning with a washing vacuum cleaner (see abov...e), the HEPA filter, in fact, is not needed at all (in many models, it is recommended to remove it altogether for such cases). So if you plan to use such a vacuum cleaner mainly for washing, you can ignore this parameter. Another specific case is industrial units (see "Type"): they are often used for rough cleaning of large debris, where thorough air filtration is not required.

Additional operating modes

Additional modes of operation provided by the robot cleaner (see "Product type").

First of all, let us clarify that the standard modes, in this case, include two formats of cleaning at standard power — continuous, in which the vacuum cleaner carefully cleans the entire room (or its specified area), and chaotic, in which it moves randomly within the working area. Other ways of working are considered additional; their list is given in this paragraph. Among the most common additional modes are spot cleaning (Spot), perimeter cleaning (Edge), and turbo mode. In addition, a fairly popular function is the Zigzag. Here is a detailed description of the different options:

— Spot cleaning (Spot). A mode that allows you to use the vacuum cleaner for targeted cleaning of a relatively small area of the room — for example, when spilling a small amount of debris. Most often, this programme works as follows: the robot moves to the centre of a user-defined zone, and then starts moving from this point in an expanding spiral and stops at a given distance from the starting position.

— Perimeter cleaning (Edge). A mode that allows you to start the vacuum cleaner around the perimeter of a given zone. By the name, it is mainly used for cleaning along the walls of the room: a lot of dirt accumulates in these places, which are difficul...t to remove when using standard cleaning modes.

— Turbo mode. Power mode for more suction force. Usually, the movement of the vacuum cleaner, in this case, can be carried out according to any programme available in the settings — both standard (combing, random movement) and additional (Spot, Edge, Zigzag). Anyway, the turbo mode is useful primarily for cleaning carpets and other floor coverings with pile, for which the standard power of the vacuum cleaner is not enough. However, working at increased traction increases the load on the unit and increases its wear. Therefore, most models have restrictions on the maximum time of continuous operation in turbo mode and sometimes on the minimum duration of breaks between switching on this mode.

— Zigzag. Zigzag movement is a kind of transitional variant between the orderly combing of the room and the random choice of direction. Zigzag allows you to achieve greater efficiency than chaotic movements. In addition, with such a movement, it is easier to compensate for the presence of various obstacles and ensure thorough cleaning of the entire given area.

multi-map memory

Advanced models of robotic vacuum cleaners can havemulti-map memory. Thanks to this feature, when moving the robot to another floor, it does not need to reacquaint itself with the premises and build a new map. As a result, cleaning will be done faster and better.

Voice assistant

Types of voice assistants supported by the robot vacuum cleaner.

As the name implies, this function allows you to control the robot using voice commands. However, we emphasize that in this case, we are not talking about the voice recognition system built into the vacuum cleaner but about compatibility with an external device on which the corresponding voice assistant is installed — a smartphone, tablet, smart speaker, etc. Thus, to use voice control, an additional device will inevitably be required; on the other hand, there are no problems with the search for such a device nowadays. And in itself, such a control method often turns out to be more convenient than a command from the remote control or searching for the desired option in the control application.

As for specific assistants, the most popular nowadays are (in alphabetical order) Amazon Alexa, Apple Siri, Google Assistant. And in robot vacuum cleaners, compatibility can be provided both with one of them and with several at once. The specific control functionality available through the voice assistant should be specified separately for each model. It is also worth paying attention to the supported languages: for Siri, the language must be selected in the settings, for the Google Assistant, automatic language recognition is available (some adjustment may be required), and in Alexa (as of early 2021) support for the Russian language is not provided at all.

Cleaning area

Cleaning area for which the robot vacuum cleaner is designed.

It is the maximum size of the room that the device can effectively process without the need to empty the dust container or charge the battery. It is worth choosing according to this parameter with a certain margin — this will give an additional guarantee in case of various emergencies. On the other hand, you should not take too much stock: after all, a large cleaning area requires more capacious batteries and capacious dust collectors, which significantly affects the dimensions, weight, and most importantly, the price of the vacuum cleaner.

As for specific figures, the most modest models nowadays are designed for 45 – 60 m2 — this corresponds to an average apartment with 1 – 2 rooms. And in the most advanced and heavy devices of this type, the cleaning area can be 300 m2 or even more.
Dreame D9 Max often compared
Roborock S7 often compared