Comparison Roidmi F8E vs Dreame V9

Rated power consumed by the vacuum cleaner. In models with power adjustment (see below), the maximum value is taken into account in this case. We are talking about the characteristics of the installed motor, which is the main, and in most vacuum cleaners, the only consumer of energy.

Higher power increases suction force and improves overall cleaning efficiency. In addition, a more powerful unit is easier to equip with a capacious dust collector. On the other hand, only vacuum cleaners of the same type with the same types of dust collectors can be directly compared by this parameter (see above for both). And even in such cases, the actual suction force (see below) may be different — and it is it that determines the real efficiency. However, the total power also allows you to generally evaluate the capabilities of the vacuum cleaner, including in comparison: a 1500 W model will significantly outperform its 800 W counterpart in efficiency (although it is impossible to say exactly by how much). But what definitely depends on this indicator is energy consumption.

As for specific power values, they are largely related to the type of device. For example, handheld models, robots and uproght units have low power — less than 1500 W(and often noticeably less). Such values are quite popular among other types of vacuum cleaners (conventional, industrial, workshop, etc.), but among them there are already more solid indicators — ...f="/list/90/pr-1067/">1500 – 1750 W, 1750 – 2000 W and even more than 2000 W.

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).

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.

The rated voltage of the battery used in the vacuum cleaner with the corresponding type of power supply (see above).

Initially, manufacturers select the characteristics of the battery (including voltage) in such a way that the vacuum cleaner can be guaranteed to deliver the power claimed in the specifications. Therefore, when choosing this indicator often does not play a decisive role. However, it can also be useful in such cases — for the most reliable comparison between models with different battery capacities in ampere-hours. See "Battery capacity" for details.

In addition, voltage data can be useful during operation — for example, to find a spare/replacement battery or a third-party charger.

The capacity of the battery installed in the vacuum cleaner.

Recall that batteries are used in all robots, as well as other types of vacuum cleaners for which mobility is important; see "Power supply" for details. As for battery capacity, theoretically, a larger battery allows you to work longer without recharging. However, there are nuances. Firstly, the actual battery life of the unit will also depend on its type, power and some features of the functionality. Secondly, the actual battery capacity is determined not only by this indicator but also by the voltage in volts. So if these batteries differ in voltage, you need to convert their capacity into watt-hours and use this data when comparing. These calculations are described in more detail in special sources.

In light of all this, only vacuum cleaners with similar specifications can be directly compared in terms of battery capacity. And it is best to evaluate the actual battery life by the directly claimed operating time.

The operating time of a battery-powered vacuum cleaner (see "Power supply") on a single battery charge.

Usually, the average operating time in normal mode is indicated here. Accordingly, in fact, the battery life of the vacuum cleaner may differ slightly from the claimed one, depending on the chosen application format. Nevertheless, the operating time indicated in the specifications is a fairly reliable indicator; it can be used both for a general assessment of battery life and for comparing the selected vacuum cleaner with other models.

Separately, we note that increasing battery life requires either the use of more capacious (and therefore more expensive and heavier) batteries or a decrease in engine power (and the efficiency of the unit as a whole). So it is worth looking specifically for a long working vacuum cleaner if these moments are outweighed by a long operating time.

The time required to charge the cordless vacuum cleaner fully (see "Power supply").

Larger batteries tend to take longer to charge. On the other hand, modern batteries can use various solutions that speed up the process, so there is no strict dependence here.

Separately, we note that the speed of charging batteries is usually uneven: at first, the process is fast, then it gradually slows down. So if, for example, the specifications indicate a charging time of 2 hours, then charging from 0 to 50% will take a little less than an hour, and from 50% to 100% the remaining time.

The presence of an indicator in the vacuum cleaner that displays the current battery charge level. The design and functionality of such an indicator may be different. Often the simplest LED indicators are used, allowing only an approximate estimate of the remaining energy. Also, note that the charge level indicator may not be placed on the body of the vacuum cleaner but on the battery itself. Nevertheless, this feature anyway provides additional convenience, makes it easier to monitor the state of the battery and reduces the risk of being left with a dead battery at the wrong time.

The noise level produced by the vacuum cleaner during operation. Usually, the value for normal operation at maximum engine power is indicated here. With less power, the loudness of the unit may be lower, but the key is precisely the maximum indicator.

Regarding specific numbers, keep in mind that the decibel used to measure the noise level is a non-linear quantity. Therefore, it is worth evaluating specific indicators using special comparative tables. In general, vacuum cleaners are quite noisy appliances; so in this case, models are considered quiet if this indicator does not exceed 65 dB — this is the level of a loud conversation between 2 – 3 people at a distance of 1 m. The quietest of these models give out only 40 dB — this is the average volume of a person’s speech in normal tones (and the minimum volume allowed for constant noise sources in living quarters during the day). For louder units, the comparison table looks like this:

— 66 – 70 dB — loud conversations between several groups of people at a distance of about 1 m;
— 71 – 75 dB — the volume of a cry or laughter in full voice at a distance of about 1 m;
— 76 – 80 dB — the volume of a mechanical alarm clock or the engine of an old truck;
— more than 80 dB — a very high noise level, exceeding the level of a loud scr...eam; when working with a vacuum cleaner having such specifications for a long time, it is highly desirable to use hearing protection.

Also note that the noise level largely depends on the engine power, as well as some other features (for example, it is strongly affected by the presence of an aquafilter — see "Dust collector"). At the same time, there is no hard connection here, and units with a similar set of specifications can differ markedly in actual loudness. In such cases, when choosing here, it is worth proceeding from the fact that a quieter vacuum cleaner will be more comfortable to use. However, it will most likely cost noticeably more.