Extract volume. How to calculate the exhaust power for high-quality air purification? Power is an important device selection parameter

Which company is better to buy a hood?

Below we present a small list of manufacturers.

These firms have long earned trust in their products. BOSH, Siemens, Miele, Gaggenau, Kuppersbusch

These firms are a good alternative to famous brands, because. hoods are their main focus. And the price / quality ratio is pretty good. Cata, Krona, Jet Air, Elica, Elikor, Faber, Fox, Fagor MAAN, Turbo, Fabriano

What hood size to choose?

The size when choosing a hood plays an important role. It should be either the same as the size of the gas stove or hob, or slightly larger. This will provide the most complete collection of contaminants.
Standard hood sizes are 50, 60, 70, 90, 100 and 120 cm wide.

How to place the hood?

It is better to place the hood above the hob at a height of 65-70 cm. If it is lower, it will interfere with you while cooking, and you may touch it with your head. If you hang it higher, it may not cope with its tasks and all the smell you have will remain in the kitchen.

What power to choose for the hood?

Selecting the power of the hood motor requires some calculations.

To do this, you need to know the parameters of the room and use a simple formula:
Q = (A (kitchen length) x B (kitchen width) x C (ceiling height) x 12 + 15% = m3/h
That is, by multiplying all the parameters of the kitchen, we find out its volume. We multiply the resulting figure by 12 (the SES norm for updating the air in kitchens is 12 times per hour). We add 15% (resistance of the ventilation outlet). For example, if the length of your kitchen is 3 m, width 4 m, ceiling height 2.5 m, then we calculate the optimal hood power as follows:

(3 x 4 x 2.5) x 12 + 15% = 414 m3/h

For this kitchen, an extractor hood with a capacity of 414 m3 / h will be optimal.

Please note that each turn of the corrugated pipe reduces its performance by
10% . Therefore, for each rotation, we add 10% to the formula.

If the hood will be operated in recirculation mode (an alternative to connecting to an exhaust shaft) by installing carbon filters, then 30% should be added to the calculated power.

If you have your own house, then 600 cubic meters per hour will not hurt you.

The suction power is also affected by the ventilation system. Namely, how and what (diameter of the ventilation duct) ventilation pipes are laid. If you have a lot of climbs and turns, then you can safely add 10% to the power for each turn or climb. The diameter of the ventilation duct should be the same as at the outlet of the hood. When buying, you should pay attention to this in order to buy adapters for your channel size in advance.

It is also impossible to miss the modern layouts, when the living room is combined with the kitchen. Here you can safely add 30%.
And we must not forget that the hood is needed to purify dirty air, and not to remove tobacco smoke. But it certainly helps a lot with this. To remove the smell of tobacco, there are special anti-smoking fresheners.
In terms of power, you can also add that it also makes no sense to install hoods of 1000 cubic meters / hour, because. your performance of the ventilation ducts will not pull. If you live in a high-rise building, then we will install a powerful hood, you can provoke a scandal with your neighbors. It is they who will push through the dirty air taken from you.

I myself would personally take 600 cubic meters / hour to the kitchen of 8 m2 (I have one). Because I am not going to work at constant power, thereby leaving a margin of reliability for the hood.

How many speeds does the extractor have?

The standard set for the hood is 3 speeds. Models are different and sometimes it reaches 5. At the minimum speed, the hood will allow you to keep the kitchen air clean. At maximum speed, you can get rid of odors that are unpleasant to you in the shortest possible time.

What design to buy a hood?

Corner hoods. The most important feature of these hoods is the ability to install it in a corner. They come in retro, Hi-Tech and classic (dome) styles.

Island hoods. These hoods are expensive. And have the ability to connect to the ceiling. As a basis, they have very high power and are designed for large country kitchens.

Decorative hoods. This class is the most numerous of those offered, both in price and design. There is also a wide variety of manufacturers. Both domestic and foreign. By capacity there are from 150 to 1000 cubic meters / hour. At a price of 3,000 rubles. up to 90,000 rubles depends again on the style of execution.

Built-in hoods. Interest in this type of hood is due to the fact that the entire body is hidden in a furniture drawer. The price due to this factor is of course cheaper. The more functionality, the more expensive.
In such hoods, either one or two motors are installed. Management as a basis slider. In some models, it is possible to extend the bottom panel, due to this, the capture area increases.

Classic (flat) hoods. For options when the hood is needed, but there is nowhere to hang it. At prices, they are the cheapest from 1,500 to 7,000 rubles. In terms of power, they are certainly inferior to the rest. As a basis there is one motor, but there are also twin-engine ones. Of course, this affects the noise level.

What kind of lighting does the hood have?
The lighting of the hood is usually carried out with incandescent lamps of 20-40 W. But in more expensive models put neon or halogen lamps. So by the way, of course, the more power, the better the illumination of the working area. We would recommend paying attention to the power of lamps from 20 watts. There are also different lamp arrangements. Lighting devices are installed either closer to the wall, or closer to

What is the exhaust control?

The hood control is push-button and touch. In addition, they are also equipped with many additional functions, such as a filter contamination indicator, an operating mode number, a timer. Some manufacturers have auto-on/off features. For example, KRONA hoods turn off automatically after 5, 10, 15 or 20 minutes, Cata after 15 minutes, and Faber after 15, 30 or 60 minutes.

What modes are there in hoods?

The hoods have air extraction and recirculation modes. In extraction mode, polluted air is taken from the kitchen and discharged into the ventilation system or through a hole in the wall. In recirculation mode, air is sucked in from the kitchen, cleaned through filters and thrown back into the kitchen. In the exhaust mode, it is necessary to close the windows in the kitchen and open the door, thereby ensuring the exhaust of air from other rooms and preventing the opposite effect.

What are the filters in the hood and their purpose?

Coarse filters. They are designed to trap grease and soot. They are made from metal or synthetic materials in the form of a mesh. They are reusable: removed, washed and installed. Carbon filters. They are designed to purify the air, clean from small particles of fat, soot, smell.

What is the noise level of the hoods?

Typically, the noise level in the hoods ranges from 32 to 62 dB, this is with a capacity of 200 to 800 m3 / h. The higher the performance, the higher the noise level. The diameter and length of the ventilation ducts, the size of the kitchen and other parameters also have a great influence. When buying, you need to look in the passport for the noise level at maximum performance. The normal noise level is 60 dB.

Musty stale air in the living room, fumes and rich smells of food in the kitchen, exhausts and amber of fuels and lubricants in the garage - such conditions suggest that how to calculate draw power.

Hood power calculator

Somewhat earlier, such a factor influencing the choice as the noise emitted by the exhaust system was mentioned. We should not forget about this property of turbines built into kitchen ventilation, because it directly depends on the power, that is, the number of revolutions per minute, as well as on the diameter of the channel and the number of elbows in it, the distance to the ventilation shaft, the density of filters and other trifles. Therefore, you always need to find a compromise between the desire to buy more powerful equipment and the desire to spend evenings in the kitchen in a cozy environment.

According to the facts, the comfortable noise threshold in the room is no more than 30 decibels (db), this is the so-called background noise - the distant roar of motors of cars passing along the street, birds chirping outside the window, the murmur of water in the pipes. At the lowest speed, a truly quiet hood emits no more than 35 dB, at the second speed - within 45, at the third - about 50 dB. When compared to household noise, this is equivalent to a whisper at 5 meters from you, a conversation at 10 meters and a quiet conversation at 3 meters, respectively. Accordingly, a noise threshold of 55 dB can be considered uncomfortable, given that there is always enough work in the kitchen.

If you do not pay attention to decibels, then the calculation of the hood is very simple. You have a certain volume of the room, the so-called cubic capacity, within these limits the air must be constantly updated, preferably at least 12 times per hour. So we first calculate the volume of the room, multiplying its length, width (this will give us the area) and height V=S. H, and then we multiply the result by the same 12 complete air purifications. However, this number of ventilations is usually calculated on the maximum load of the hood, that is, it will mean prohibitive noise in the kitchen during the same hour. Therefore, be sure to add at least 15% to the result of multiplications (ideally 30%) and get V. 12 . 15=P, that is, the power determined by cubic meters per hour (m 3 / h).

The choice of hood is largely influenced by the type of hob, due to the different amounts of combustion products emitted into the air. So, for an electric panel, they are completely absent, as well as for an induction panel, and for a gas one, along with soot. Therefore, for the first two in a 3x4 meter kitchen, a minimum capacity of 486 cubic meters per hour is sufficient, and for the third, at least 650 cubic meters of air for the same time. Accordingly, the coefficient of air renewal in the room for electric hobs is taken as 15, and for gas hobs 20 times per hour. It is logical that if the doorway is devoid of a closing sash and has turned into an arch, the power should be increased due to the spread of odors and combustion products, and for the same surfaces it will already be within 600 and 800 m 3 / h, respectively.

Unlike the kitchen, the room reserved for the car should be much better ventilated. And this is logical, since it is difficult to compare a gas stove and an internal combustion engine in terms of the amount of combustion products released. Therefore, before you calculate the hood, you need to decide which vehicles and in what quantity you will put there. The emissions of a car and a truck vary greatly in volume and content of harmful substances, especially if the former requires high-octane gasoline, and the latter quietly consumes diesel fuel. According to the air exchange standards established by ABOK, it is necessary to provide air flow in the amount of 180 cubic meters per hour for one passenger car.

It is not recommended to make many bends, because the more there are, the stronger the noise of the exhaust system. In addition, each knee reduces ventilation efficiency by approximately 10%. In order for the air drawn out by the turbine to be replenished at the same speed, several inlet openings can be made by supplying them with retraction fans. The entrance channels are located closer to the floor, at a distance of 40 centimeters from it, and are covered with a fine mesh to prevent the penetration of rodents.

Choosing a hood for the kitchen should begin with determining the technical characteristics of the device you like. Many users do not study this issue well enough, paying attention only to the dimensions and design of the device. As a result, they acquire a device that is too weak, which cannot cope with the air masses in the room, or, on the contrary, is too powerful, creating noise and consuming a lot of electricity. To avoid these problems, you need to know how to calculate the hood in accordance with the dimensions and features of the kitchen.

Among the technical characteristics, special attention should be paid to the power and performance of the device. These indicators reflect the volume of air masses that the hood passes through itself for a certain time, as well as the energy spent on this process. If you correctly calculate the volume of air in the room and take into account additional factors, you can accurately determine how long it takes the appliance to fully ventilate the kitchen. This will allow you not to make a mistake with the choice of an exhaust device and subsequently use it as efficiently and economically as possible.
In this article, we will tell you how to calculate the power of the hood for the kitchen so that it successfully copes with the ventilation of the room.

Types of hoods for the kitchen

Exhaust devices are divided into several types according to the method of operation, design and mounting option. The type of device often determines the degree of its performance, therefore, at the first stage of selection, it is worth remembering this pattern.

1. Flow hoods are models equipped with a dome that remove polluted air into the general ventilation system through the chimney. Such hoods can have a fairly high power.
2. Recirculation - compact hoods, the principle of operation of which is to conduct air masses through a system of cleaning filters. These models, as a rule, have less power than flow models, they pass a limited amount of air through themselves.

The rules for calculating performance for different types of hoods are somewhat different. In a recirculation system, the main factor is the power of the motor, and in a flow system, the efficiency of air output to the ventilation shaft.

The formula for calculating the performance of a recirculating hood

The standard calculation of the required performance of the hood for the kitchen is carried out according to the following formula:

where: N is the design capacity, m³/h;
S - kitchen area, m²;
h - ceiling height, m;
12 - adopted by the SES;
1.3 is the minimum stock factor.

Hood performance calculator

• when using an electric stove;
• kitchen with closed doors and windows, separated from other rooms;
• the shape of the room is rectangular.

It is important to note that the calculation formula allows you to find out what volumes of air the device will process at maximum power and speed. Of course, in real conditions, the device cannot constantly operate in the most energy-consuming mode. To get a more accurate result, it is recommended to add 15–20% to the final figure, so you will calculate the performance of the kitchen hood for efficient operation in medium mode.

If a gas stove is used for cooking, then the coefficient 12 should be changed to 20 without hesitation. In this case, in addition to fumes, ventilation will also have to remove gas combustion products from the kitchen. If the design has a carbon filter, it is worth adding 20 to 30%, as it creates additional resistance to the incoming air.

Calculation of the performance of a flow-through exhaust system

The calculation of the exhaust power with an air duct is also carried out by calculating the volume of air masses in the room. However, the performance of such a system is greatly influenced by the throughput of the duct. If the air exhaust duct is not designed correctly, a high power appliance will not work efficiently and may even fail. Frequent problems that arise in this case are a high level of noise and overheating of the electrical parts of the device.

In almost all apartment buildings, air ducts do not exceed 12–13 cm in diameter. Up to 400 m³ of air can be removed through them per hour. This figure should be guided by when choosing a hood for the kitchen - if you buy a device with a higher performance, the power consumption will increase with a slight increase in performance.

An important factor is the length and shape of the chimney pipe. If the exit to the ventilation shaft is too far from the installation site of the hood, and the channel itself has irregularities and corners, the air will pass through it at a lower speed. In this case, the installation of a powerful exhaust device is also unjustified.

Influence of the shape of the hood on the power level

In addition to differences in the way they work, cooker hoods also differ in the type of construction.

1. Dome or fireplace. This design is made in the form of a trapezoid or a cone. Thanks to this device, it creates additional natural draft of air. It can have different power, up to the highest rates.
2. T-shaped. A simplified version of the hood with a chimney, instead of a dome, rectangular panels are used. In a compact form, it can be built into furniture. With a wide pulling surface, it often has a high performance.
3. Inclined. A device with a chimney, the lower part of which is located at an angle with respect to the wall. This shape provides good air draft and saves space. Possesses high and average indicators of efficiency.
4. Wall. A device with filters that purify the air and bring it back into the room. Has no outlet to ventilation. Has an average power level.
5. Hanging or sliding. Convenient and inconspicuous, but inefficient models of recirculation hoods. As a rule, they have low power. Used in small kitchens or when providing an additional ventilation system.

Thus, we can conclude that the best option for spacious rooms is the classic fireplace or T-shaped ventilation, as well as some of the inclined models. They can provide enough power to ventilate the kitchen. In small rooms, you can also install a wall-mounted recirculation model, however, in this case, you need to carefully calculate the performance of the hood and the volume of air masses.

Hood dimensions as a performance indicator

When calculating the extractor hood power for a kitchen, it is logical to assume that the larger the extracting surface of the appliance, the more air it can pass during operation. Accordingly, small (built-in or folding) models of hoods have low performance indicators, and large dome models have the highest ones.

This is the only external factor by which you can "determine" the power of the device by eye. However, today this approach cannot be called correct. Modern hoods can be highly efficient even with a compact design. An example of this is the T-shaped and inclined hoods, which, in the absence of an impressive dome, do an excellent job of ventilating even spacious rooms.

Noise level at different device performance

noise level

When a large volume of air passes through the exhaust ducts, a sound naturally arises, which grows when the motor operates with high power. In residential areas, noise can interfere with a comfortable stay in the kitchen and even penetrate into other rooms. Therefore, it is very important to choose a hood of such power that the noise level during its operation does not exceed the permissible limits.

Small hoods with low power have the lowest noise level - their performance does not exceed 40–45 decibels. This is a fairly comfortable level for the constant operation of the device in automatic mode. However, when choosing such a model, you will have to sacrifice the efficiency of its work.

Kitchen hoods with high power have high noise levels and can create discomfort when working in small rooms. Experts recommend turning on these devices “to the fullest” only in emergency cases, but for daily use, set the settings to average. Then the hood will not make loud sounds during operation.

Features of calculating the power of a kitchen hood

Let's sum up to answer the question of how to choose a hood for the kitchen in terms of power? To do this, you should take into account a number of factors that we have already noted above:

• Calculate the volume of air in the room.
• Knowing the diameter of the duct and its length.
• Having made amendments in accordance with the presence of filtration systems, pipe bends.
• Noting the type of stove and the frequency of its use.
• Determining a comfortable noise level.

In the complex, the calculation of the performance of the hood for the kitchen according to these parameters will provide you with efficient and economical operation of the device. You can read about other features of the choice of ventilation systems in special sections of our website.

In recent days, the range of kitchen hoods has been increasing more and more. To the delight of the consumer, there is an increasing variety of shapes, materials and sizes. But you need to stop only on the outside. After all, the main task that the hood should perform is to remove unpleasant odors, grease, burning, soot and fumes. To maximize the efficiency of this device, you need to learn how to calculate the power of the hood for the kitchen. You should be aware of how much air your hood passes in a certain unit of time.

Varieties of kitchen hoods

A kitchen hood is a household appliance, the design of which includes an electric motor with filters and fans. First, it is worth mentioning what designs of hoods are.

They are integrated (embedded), they are installed inside a hanging cabinet above the stove. With this design, only the grate of the filter trapping grease will be visible. But this hood has one drawback. Due to the fact that it is built into the cabinet, it resonates during operation and the noise increases.

There are also wall models. They are mounted on the wall above the stove or under the kitchen hanging cabinet. There is also such an option as replacing the hood with the hanging cabinet itself.

Not so long ago, island hoods became popular. They are used in kitchens with a non-standard layout and are attached to the ceiling. The corner model is suitable when you need to install it in the corner of the kitchen.
The width of the hood should not be less than the width of the plate, or preferably more than the width.

We list the operating modes of different hoods:

1. Extract mode. In this case, the air is cleaned of grease particles by passing through a grease filter. There are two types of filters, reusable and disposable. Then the air is removed from the room through a special ventilation duct. But this type of hood needs a constant supply of fresh air, and therefore, during its operation, you need to keep the window open. Also, this mode requires mandatory installation of an air duct.
2. recirculation mode. In this case, the air is cleaned of both fat and odor. The air passes not only through the grease filter, but also through the carbon filter. After which the air is returned back to the kitchen. But carbon filters require annual replacement. But not all hoods have this mode of operation.

This equipment will purify the air and save the budget for redecorating the kitchen or furniture in the bathroom (due to high humidity).

Suction power calculation

Extraction power is a representation of the number of cubic meters of air sucked in during an hour by the hood in extraction mode. During cooking, depending on the intensity of evaporation, the air in the room is updated about 10 - 15 times per hour.

This parameter can be calculated using the formula:

Extraction power = S * h * K, where:

S is the area of ​​the room; h is the height of the room; K - room type coefficient: kitchen - 12; bathroom - 7; toilet - 5.

Kitchen area: 15 sq.m, ceiling height 2.7m

15 X 2.7 X 12 = 486

Each meter from the mine to the equipment 10%
+ each pipe bend 10%
+ we take into account the reserve power of 10-20% (in case the food burns)

If your kitchen or bathroom is 15m2 with a ceiling height of 2.7m, the ventilation shaft has a normal air draft, the distance to it does not exceed 0.5m, there are no bends in the pipe, and the hood will work in the air outlet mode, then we recommend buying an hood with a capacity of: 580 m.cub./hour.

Also, to calculate the power of a kitchen hood, you can use our online calculator:

Important! The hood loses its performance factor if the air outlet has sharp bends in the channel. Two 45° bends are considered the best option than one 90° bend. Performance is lost with each meter and bend of the duct pipe by 5-10%. Corrugated channels create noise during operation and reduce the performance of the hood. Don't forget that during recirculation, the power of the device drops by 25%.

Which hood to choose?

With the correct calculation of the performance of the hood for the kitchen and the calculation of its power, it will solve a large number of problems. Here are just a few of them:

• the appearance of fumes from heating devices (for example, from a stove);
• during the preparation of some dishes, the appearance of unpleasant odors;
• constantly occurring plaque on the ceiling and walls of the kitchen.

It is most important to choose a model with the highest optimum noise-to-power ratio.

Noise options:

• 30dB - typical noise level in a quiet room;
• 35 dB - noise that occurs when the hood is operating in a very quiet mode, this noise is heard as a whisper of a person at a distance of 4-5 m .;
• 45 dB - the hood, which works quite quietly, is equivalent to a conversation at a distance of 10 m, or soft music;
• 50 dB - noise generated during a normally operating hood; corresponds to a conversation at a distance of 2-3 m;
• more than 50 dB - a very distracting increased noise level, which resembles a loud conversation at a distance of 5 m.

Hood manufacturers are working hard to reduce noise levels. For example: silent fan motors with special bearings, sound-absorbing pads, hoods with two fans and hoods with an external motor (outdoors).

In addition to the basic functions, the hood can also be an additional power source. For this, various types of lamps are used: fluorescent, halogen, incandescent. Fluorescent lamps give a dim, uniform light, the disadvantage of such lighting is that the natural color of the food is distorted with such lighting. This is the most economical option. Incandescent lamps also distort the color, distorting it towards red shades. More natural colors look in the light of halogen lamps.

It is believed that a kitchen of 6-8 m2 can do with a primitive hood. If we take into account the parameters and substitute them into the formula above, then this is the result we get. But logically, the spread of odors in a small room is faster. In addition, the concentration of combustion products, as well as evaporation from the gas of the stove itself (if it is gas) is much higher.

It has long been proven that the concentration of such vapors is absolutely independent of the size of the room. But there is a legend among users that the hood should carry out full ventilation, regardless of any conditions. But this is a mistake. The efficiency of the hood depends both on the organization of the air flow and on the type of installation.

Experts advise choosing a hood with a power reserve and operating it in medium mode. This trick will increase the life of the hood and reduce the noise level during its operation.

It should always be remembered that the hood is an integral element of ventilation, but it does not include a complete 100% circulation of air inflow and outflow!

Properly calculated power plays a significant role when buying a device. Specific odors during cooking and frying food, fumes, burning, smoke - all this is removed by this device. However, this is only possible when its performance meets the desired characteristics.

In order not to purchase just an elegant kitchen accessory instead of a working device, you need to calculate the power of the hood before going to the store. And for the correct calculation of the formula, you need to understand the design and principle of operation of the exhaust device. All the necessary information can be found in this article.

What is power calculation for?

The engine performance will determine how much exhaust air the hood can replace per hour and it is measured in cubic meters. The main task of this device is the destruction of specific odors in the kitchen, as well as the timely removal of fat, soot, fumes, which are inevitably present during cooking and frying food.

How to calculate the hood in the kitchen so that the performance complies with the conditions of SNiP. Having picked up and installed an extract of the required power, the costs of it will be compensated over time by saving detergents.

Factors affecting power calculation

To calculate the performance of a kitchen hood, the formula is used:

Q=s × h × 12.

It takes into account only the size of the room, the height to the ceiling and the frequency of air exchange. This is a correct calculation, but not a complete one.

In addition to the area of ​​\u200b\u200bthe kitchen, the following parameters must be considered:

• family composition (consumption of clean air must comply with sanitary standards per person);
• cooking frequency;
• what dishes are prepared (with fatty broth or healthy food);
• section, length, material of air ducts.

And also the type of stove and the location of the room affect the power of the device. Let's take a closer look at the last two parameters.

Plate type

Undoubtedly, the area and type of plate has an impact on the performance of the hood. The type of stove affects the amount of waste in the form of scale, burning, getting into the air at the time of frying meat, boiling borscht, or healthy food with vegetables alone. At the same time, the flow of fresh air into the room also occurs in different ways. Consequently, the air exchange rate also changes.

Let's take a closer look at how this happens:

1. The calculation of the hood for the kitchen in the presence of an electric stove differs from the classical one, since combustion products do not penetrate into the air, except for steam from cooking food. As a rule, the air exchange rate for these electric stoves is increased from 12 to 15 when calculating, while the classic formula will also change as follows:

Q=S×H×15.

1. At the time when a gas stove is used, the air exchange rate increases to 20. This is due to the fact that, in addition to fumes, combustion products in the form of burning, soot, burnt, and so on enter the air space above the stove. Here the performance calculation formula will be different: S × H × 20.
2. It would be wrong to say unequivocally that with a hob with an area of ​​​​65 cm, the hood should be more productive than with a smaller stove of 55 cm. However, logically, this can be assumed, because large hoods process air mass from a plate of a larger surface. It is simply impossible to completely remove all harmful particles and odors from cooking with low power.

It is important not to make mistakes when calculating the device parameters. It is much easier to calculate the power of the hood, if you take into account the main aspects.

Kitchen location

When calculating the performance of a kitchen hood, the type, area and isolation of it are taken into account. It can be: an apartment in the form of a studio, a kitchen and a living room at the same time, a separate kitchen. And also in the opening, instead of the door, an arch is sometimes installed, or the door is constantly open, in which case these parameters must be taken into account.

Here, the kitchen, one way or another, is combined with the adjacent room, so the conditions for calculating the performance of the hood increase several times. Thus, when calculating the power of the device, these additional parameters in the adjacent room must also be taken into account, thereby fully providing fresh air to your household.

There is an opinion among users that in a small kitchen a hood with a small power is enough. But in a small room, odors disperse faster, which means more polluted air.

Accordingly, in order for the air to be clean, air exchange must occur more often. However, a hood with low power simply cannot provide this, or the engine will overheat and burn out sooner or later.

The greater the power of the kitchen hood, the sooner the air above the stove in the kitchen is cleaned. Performance can be quickly calculated from the table below.

Extractor performance

In small kitchens, it is allowed to install low-power exhaust devices with a capacity of 200-300 m³ / h. The price of these devices is relatively small and they perform their task under certain conditions: cooking occurs no more than two or three times a day and in small volumes. With more frequent “cooking”, it is better to use a classic hood with a capacity of 600 m³ / h.

On a note! The performance of the device is indicated in m³ / h. Sometimes it is called power. However, this value cannot be used as power consumption, which is specified in watts (W).

Performance must comply with SNiP standards. During an hour of operation, air is replaced approximately 10-12 times. For calculations, as a rule, they take the number 12. If the household often smokes in the kitchen, then the performance of the unit increases by 20-30%.

Power calculation

As already known, to accelerate the calculation of the performance of the device, the following formula is used:

P=S×H×12, where

P– calculated power value;

S- the area of ​​the room;

H- ceiling height;

12 - replacement of the air mass in the kitchen according to SNiP.

This formulation is suitable for relatively small volumes of air in the room, up to 40 m³. With its help, the smallest power of the hood is determined. In practice, this value can change, as other aspects also influence it: the type of hob and air circulation, the composition of the family and the location of the kitchen.

For an illustrative example, let's calculate the performance of the hood for a kitchen measuring 12 m 2.

For this, the following initial data are given:

• room dimensions 12 m2 (3 × 4);
• distance to the ceiling - 2.8 m;
• family members - 3 people;
• the electric stove is used 3 times a day, for it the air exchange rate is 15 according to sanitary standards (coefficient 1.5);
• air duct available.

To calculate the performance of the hood, it is necessary to substitute the input numerical values ​​​​into the formula:

(3 x 4) x 2.8 x 12 x 1.5 = 604.8 m³/h

Therefore, the calculations showed that for a kitchen with dimensions of 12 m 2, the productivity of the apparatus is at least 600 m³ / h. That is, it moves a given mass of air in an hour. It will not be difficult to choose a product with these parameters in any price range.

What to look out for

When choosing a device, first of all, you need to find out if there is a possibility of connecting to exhaust ventilation. If the room has this bandwidth - very good. In the case when there is no possibility of connection, you will have to purchase a hood with special filters built into the device.

Hood type

Devices are divided according to the principle of operation, and more specifically, according to the method of removing the air flow from the hob.

There are two types of exhaust devices:

• flowing;
• recycling.

1. The first type of instrument designed to connect it to the ventilation duct and to exhaust the exhaust air to the outside. Moreover, such hoods are combined. They can bring the air flow outside, or they can immediately return it back, having previously passed it through the filters.

Such modes are selected at the will of the owner, basically, the second option is convenient to use in winter, so as not to cool the kitchen with cold air during replacement. Before connecting the hood, you need to check the draft in the channel, for this it is enough to bring the flame of a candle or match to the hole and make sure that it deviates towards the channel.

If the draft in the well is weak, then you must first clean it, otherwise the hood will not fully cope with its task. Another option is to bring a separate ventilation duct outside with further insulation.

1. Second view- recirculation is equipped with a filter system, and such devices do not need to be connected to a ventilation duct. In these hoods, the purification of the air mass takes place in two stages. First, particles of fat, burning, and scale are removed by mesh filter elements.

Then the air mass passes the second cleaning through activated carbon, after which all unpleasant odors disappear and then the air returns back to the kitchen. During operation of the unit, the filters resist air circulation, and this must also be taken into account when calculating the performance. It is recommended to increase the rate for such units by about 20-30%.

Noise level

When buying a hood for the kitchen, you need to pay attention to its noise level, since the sounds produced by various household appliances can cause your discomfort. How to find out the noise level from the installed device? This indicator is indicated in the instructions from the manufacturer. Modern hoods have a noise value of 30 to 70 dB.

An acceptable indicator according to SNiP is a level from 30 to 45 dB. In the case when the digital value of the hood is greater, then its work will be loud. The more massive the walls of the exhaust device, the quieter it will work, since all sounds will be absorbed inside the device.

Sometimes manufacturers make soundproofing outside the unit, using different sound-absorbing materials for this. And also, in some models, instead of one, two fans with less power are built-in, which significantly affects the overall noise level downwards.

As a result of these design changes, modern hoods have the lowest noise level.

1. Performance. The more powerful the device, the more effectively it will set the air in motion. Therefore, with such work, it will create more noise. Therefore, you should not purchase a hood with a power exceeding the calculated one for this room.
2. Number of operating modes. Choose a hood for the kitchen with several modes. In this way, noise can be reduced by setting the process to the minimum value. When choosing, you do not need to buy a model with a noise level of more than 45 dB.
3. Noise level value. Periodically clean the filters of the first stage and change the carbon filter elements of the second stage in a timely manner, since they also significantly increase the noise level in a dirty state.

Finally

It is not easy for an ordinary man in the street to navigate and make the right choice among the presented models of exhaust devices. At the same time, if the device is purchased with the appropriate power, the right size, then the operation of this unit will allow it to provide a pleasant atmosphere and a healthy microclimate in the apartment.