Comparison Karcher WD 3 Premium vs Karcher WD 4 Premium

The type of dust collector provided in the design of the vacuum cleaner.

Nowadays, there are three main types of dust collectors — a regular bag, a cyclone system and an aquafilter. Also, in some vacuum cleaners (in particular, industrial and fireplace models — see "Product type") dust collectors in the form of rigid containers (tanks) can be used without additional equipment. For such models, the type of dust collector in our catalogue is not specified. As for the three main types, here are their features:

— Bag. A dust collector in the form of a soft bag, simultaneously plays the role of one of the filters: air passes through the walls of the bag, and most of the contaminants are retained. Such containers are simple and inexpensive, while they can be made quite roomy. In addition, the vacuum cleaner with a bag remains operational in any position of the body. On the other hand, as the bag fills up, suction efficiency drops noticeably; and the cleaning procedure is usually quite troublesome — in particular, a lot of dust is raised into the air. Disposable bags, which are available for many models as an additional accessory, are deprived of such a drawback. However, on the other hand, the purchase of such bags is associated with additional expenses. As a result, this type of dust collector, although very popular in modern vacuum cleaners, is much les...s common than the "cyclones" described below.

— Cyclone system (bagless). Dust collector based on a cyclone type air cleaner; usually has the form of a plastic bowl of a special shape. The principle of operation of such systems is that the air flow entering the dust collector is twisted into a spiral. In this case, the centrifugal force throws debris and dust out of the formed vortex, and the collected pollution sinks to the bottom of the dust collector. One of the main advantages of "cyclones" is the ease of cleaning: just turn the container over and the contents pour out of it without additional effort, and if desired, the dust collector can be easily washed. In addition, the suction force is practically independent of the degree of filling of the bowl. However, cyclones are somewhat inferior in capacity to bags, but because of the foregoing, this point is usually not fundamental. But the unequivocal disadvantages of this option are the higher cost of the same bags; a lower suction force for the same engine power; as well as a somewhat lower efficiency of catching fine dust. In light of the latter, "cyclones" have to be equipped with additional filters, which also periodically require cleaning. It is also worth bearing in mind that such systems are most effective with a regular, strictly defined position in space. If you deviate from this standard operational position, the efficiency of the dust collector may noticeably decrease, which leads to rapid clogging of the filters.

— Aquafilter. This type of dust collector looks like a container with water: the air drawn in by the vacuum cleaner passes through the liquid, which traps most of the contaminants. Such systems are highly efficient and hygienic: they capture various contaminants well, including even fine dust, without additional filters. In addition, the air released by the vacuum cleaner is additionally humidified which is especially useful in the cold season, when heating dries the air in the room. At the same time, the procedure for cleaning the dust collector itself is very simple and convenient: after cleaning, its contents can simply be poured into the sewer, while no dust rises into the air (unlike the process of cleaning cyclones and especially bags). On the other hand, it is desirable to wash and dry aquafilters after each use, which somewhat complicates maintenance. In addition, most of these vacuum cleaners are quite expensive, the passage of air through the water creates additional noise, and the water itself significantly increases the weight of the unit.
Separately, it is worth emphasizing that the presence of an aquafilter does not mean that the vacuum cleaner is washing (see above) or at least can wet cleaning (see "Cleaning type"). Quite a few models with an aquafilter work only in a dry format — and vice versa, units with a wet cleaning function may well be equipped with other types of dust collectors.

— Aquafilter + bag. This option means that the vacuum cleaner is equipped with two types of dust collectors at once — an aquafilter and a traditional bag. The features of both are described in detail above. Here we note that such models necessarily have a wet cleaning mode (see above) and/or a water suction function — an aquafilter is used for these purposes. But the bag, anyway, is intended for traditional dry cleaning. In general, this is the most common combination of the two types of dust collectors. The other variants described below are much less common.

— Aquafilter + cyclone. A combination similar to the aquafilter with a bag described above. The delivery set of such a vacuum cleaner includes two types of containers: an aquafilter for wet cleaning and/or water suction (this function can also be provided in vacuum cleaners with purely dry cleaning), as well as a cyclone system (see above) for sry cleaning .

— Cyclone system + bag. A combination found exclusively in dry cleaning models. Similar to the combinations described above, most often we are talking about the presence of two replaceable dust collectors of different types in the kit. The specific type is chosen depending on the situation. So, the cyclone system is convenient for collecting relatively large and heavy contaminants, and the bag handles better with fine dust.

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 — ...f="/en/list/90/pr-37619/">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 this 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.

Ability of operation of the vacuum cleaner in the air blowing mode.

As the name suggests, it is the opposite of the standard suction mode. The air is not drawn into the hose but is forced out of it. This function significantly expands the functionality of the vacuum cleaner. In particular, it allows you to use the unit as a leaf blower for cleaning fallen leaves from the porch or paths in the yard, or for sweeping large debris into one pile. At the same time, blowing is especially useful where suction cannot be applied — like on paths covered with rubble. In addition, this mode can be useful for cleaning some hard-to-reach places — for example, radiators and other slots in the “hardware” of a computer: for several reasons, blowing out such places often turns out to be more effective than drawing in dirt.

Usually, to use this mode, it is enough to rearrange the hose from the main working port to the "purge" one.

The presence of a cartridge filter in the design of the vacuum cleaner.

Such a filter has the form of a ribbed (corrugated) cylinder made of special porous paper. One of its key advantages is the ease of cleaning: in relatively simple models, it is enough to remove the filter element from the vacuum cleaner and shake it out well. In more advanced units, self-cleaning may be provided at all (see below). In addition, such equipment allows you to do without a special bag (see "Dust collector") and use a simple container to collect dirt. On the other hand, cartridge filters are quite bulky and, due to their design features, are poorly suited for general purpose vacuum cleaners. So you can find such equipment mainly in specialized professional units — industrial, workshop, for fireplaces (see "Product type").

Models of replacement bags and/or other containers for waste (see "Dust collector") with which the vacuum cleaner is compatible.

This moment does not affect the functionality of the vacuum cleaner itself. However, knowing the model of the dust collector makes it much easier to find a spare or replacement dust collector. At the same time, we note that compatible models of such containers may differ markedly in specifications from the ones in the box. For example, many fabric bag vacuum cleaners also accept disposable paper bags; and some units are initially equipped with a dust collector of one type. However, if desired, they allow you to buy and install a dust collector of another type (for example, replace the bag with an aquafilter).

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 leve...l of a loud scream; 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.

The presence in the vacuum cleaner of a special device for storing nozzles and sometimes other accessories.

Such a device can be either a compartment in the case or a set of external fasteners; the latter, in particular, is quite common in industrial vacuum cleaners (see "Type"). Anyway, the attachment compartment makes it much easier to store and transport various accessories: they are not scattered or lost, and you do not need to look for a separate package for them. However, such a compartment is often not intended for all nozzles and accessories but only for the smallest ones. However, even in such cases, it makes life much easier for the user. The disadvantages of such equipment include the fact that it inevitably affects the dimensions of the case. However, in full-size vacuum cleaners — conventional, industrial, for workshop (see "Type") — this disadvantage is often not important.

The length of the power cord that is equipped with a vacuum cleaner powered by an outlet.

Here we note that manufacturers select the specific length of the cord depending on the general purpose of the unit. In general, the length of 4 – 5 m and less can be called small, 5 – 6 m — medium, 6 – 7 m and 7 – 8 m — more than average, and in some models this figure is more than 8 m. However, a lot depends on the specifics of the vacuum cleaner. For example, among conventional units there are many models with a 4-5 m wire (this is enough for cleaning on the scale of an apartment, a private house or a small office space), but for industrial solutions this is a very limited indicator.

Keep in mind that a longer power cord is not always more convenient. On the one hand, it provides more freedom when working. On the other hand, it can create inconvenience at a short distance from the outlet as well as during storage/transportation. In addition, you can use an extension cord to work away from the outlet. So when choosing, you need to take into account the specific needs of the use of a vacuum cleaner. Detailed recommendations for different situations can be found in special sources.