How to calculate the power of your kitchen hood: an important aspect of maximum air purity. Professional tips for choosing a cooker hood Calculate the power of your cooker hood online calculator

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If you are tired of constantly ventilating the kitchen, and the issue of air purification remains unresolved, then it's time to purchase a powerful hood of the desired model. Before buying, you need to make sure that you have taken into account all the nuances - from functionality to decorative features. And for this you need to get familiar with the characteristic qualities of the most common models available on sale, and also calculate their power.

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Among the huge range of cooker hoods, you can choose models of all sizes and shapes. Many buyers choose a beautiful design or a well-known brand first. But the appearance of these devices is much less important than their technical parameters - the power and volume of air pumped per unit of time.

An improperly selected hood for a given room will not be able to effectively purify the air in it. Its performance indicator, measured in m 3 / h, influences how much polluted air it can let through in an hour. With the help of special calculations using a simplified formula, you can independently choose the most suitable exhaust technology for your kitchen. A more accurate calculation can only be made by a competent engineer.

What is the difference between a hood and ventilation

The ventilation system is a network of ducts built into the walls with an exit to the outside of the building for exhausting exhaust air from the room. In this case, the inflow of fresh air occurs through door and window openings in a natural way.

This air exchange system, according to sanitary standards, must be installed in all living quarters. But it is not very effective, and even more so it is not able to localize and remove odors, fumes, soot and other "delights" of everyday life. To prevent them, forced ventilation is installed - an exhaust. It collects all the vapors from the hob, directs them through the air duct to the ventilation system.

Exhaust device

In principle, they are all similar to a vacuum cleaner, but with different functions. Modern exhaust devices come in different designs, depending on the purpose - some only remove the polluted air, while others filter it and return the already purified air back. According to the cleaning method, they are divided into flow, recirculation and combined, which combine both options.

• Flow hoods equipped with metal or plastic pipes (round, square, corrugated) for connection to the ventilation system, which can be rigid or flexible. The lower parts of the device consist of filters (), which retain soot and grease. They are disguised behind decorative panels. Fans and special motors are located inside. Behind them is an air duct connected to ventilation.
• Recirculating they work autonomously, without being connected to ventilation, therefore they do not have pipes, which makes them look more aesthetically pleasing. Inside their cases, after the fans, there are replaceable, very thin carbon filters. For coarse cleaning, the filters are made of durable aluminum, they can simply be washed with detergents. Outwardly, the principle of the structure of the cases is the same as that of the flow-through ones.

The exhaust system is powered by an electrical network. Everything is very simple - it plugs into the outlet, the button with the selected mode is pressed (denoted by numbers 1-3), the engine picks up speed. The most convenient hoods for connection are with touch displays or with remote control (using a remote control or voice commands).

Types of exhaust systems by shape and placement

According to the features of the structure of the case, there are several varieties:

• Flat- the most compact, no additional installations. Suitable for small spaces. But they have a short lifespan and must be replaced periodically. Among the flat ones, there is a variety of inclined ones, located at an angle to the hob and having a small size.
• Dome- powerful and functional, good for cleaning large rooms. They are quite large and have the shape of hemispheres or pyramids.
• Also produced cylindrical(adjustable in height), square, conical, round and other non-standard forms.
• Embedded models differ from the previous ones by the possibility of their disguise in furniture, ceiling, niche in the wall.

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According to the features of placement, there are hoods:

• suspended- mounted to the wall or ceiling in any area of ​​the kitchen;
• insular- attached to the ceiling in the center of the room;
• corner- are installed at two adjacent walls for more rational use of space.

Requirements for exhaust devices and their installation in the kitchen

To ensure the efficient and safe operation of these devices, several installation guidelines must be followed:

• The size of the intake opening must be larger than the area of ​​the hob.
• The distance from the surface of the stove to the hood should be at least 70-80 cm to avoid overheating.
• Its capacity must be such as to provide a complete air change at least 10 times per hour.
• If the kitchen does not have access to a special ventilation shaft, then it is better not to connect it to a regular one so as not to disrupt its operation, and even better - to install a recirculation model.

How to calculate the power and performance of a kitchen hood depending on the area of ​​the room

The higher the extraction power, the faster the air will be cleaned. The required performance for a given room can be found in the table, where the kitchen area and its height are taken as the basis for calculations. The lowest productivity is in the cheapest models, about 200-300 m 3 / h. They can only be installed in small kitchens and under the condition of not very frequent cooking on the stove. If the hob is used often, then the capacity should be at least 600 m 3 / h.

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The formula for calculating the power of the kitchen hood

Calculations can be done using a simplified formula yourself:

Q- extraction power (m 3 / h);

S- kitchen area;

H- the height of the kitchen;

12 - coefficient (number of air change cycles per hour)

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According to sanitary standards, 10-15 air replacement cycles should take place within an hour. The factor of 12 is the selected mean.

For example, S = 10 m2, H = 2.5 m2

With these values, it turns out:

Q = 10 × 2.5 × 12 = 300 m3 / h.

Other factors to consider

Calculations according to the formula have an average value, because other nuances must also be taken into account:

• Type of hob. For an electric stove, the reading of the coefficient can be up to 15, because besides the fumes from the products, no other substances enter the air. But with a gas stove, harmful substances from gas combustion also enter the air. In this case, the coefficient is taken from 20.
• Hood type. With a flow-through, it is necessary to take into account the throughput of the existing ventilation shaft. With recirculation, this factor does not matter.
• The layout of the premises. If there is an open entrance to the next room or a door often opens there, then it is necessary to take into account the large area of ​​the room when calculating.

Choosing a cooker hood

If funds allow you, choose a model that works in two modes - combined (). This is a more convenient option. There are already models on sale that work almost silently - with a level of no more than 40 dB. An alternative to one powerful engine is a system with two, but less power, which emit much less noise. Fans play an important role in the operation of exhaust devices. They best withstand maximum tangential and diametrical loads. The size of the hood should be larger than the area of ​​the hob so that steam and dirt do not get on the ceiling.

Video: rules for calculating the required exhaust capacity

Among the abundance of models presented for sale in stores, it is difficult to immediately navigate and make the right choice. The correct calculation of the power of the exhaust system, the choice of a model of the appropriate size and method of functioning will allow you to create a healthy microclimate and safe conditions in the house.

When choosing a ventilation device, people often only pay attention to the design of the unit or the brand. But they forget about the most important parameter - this is the power of the hood for the kitchen (performance). Without the correct selection of this parameter, even the most beautiful unit of a well-known company will not be able to cope with its task - to effectively purify the air in the room. The performance indicator determines how much contaminated air the device can pass through itself for a certain time, it is measured in m 3 / h.

The higher the power of the unit, the faster the air in the kitchen will be cleaned. The performance can be quickly calculated from the table below.

To a minimum, industrial kitchen ventilation devices have a capacity ranging from 200 to 300 cubic meters per hour. The cost of such models is low, and they cope with their task with difficulty. Installing low-power devices is possible only in small rooms, provided that you do not cook very often. For frequent cooking, it is recommended to use standard installation(capacity - about 600 cubic meters per hour), or with increased pumping volume - about 1000 m 3 / h. Accordingly, the price of such devices is higher.

Power calculation

To calculate the performance of the hood, you first need to understand what functions the appliance should perform. According to the instructions, this device should purify or remove polluted air in the kitchen. According to sanitary standards, 12 air replacement cycles must pass within one hour. That is, it must change in the room 12 times in 1 hour. Now you know where the “12” factor comes from in the performance formulas.

The formula itself looks like this: Q = S * H ​​* 12, where:

• Q is the capacity of the unit, measured in m3 / h;
• S is the area of ​​the room for which ventilation is needed;
• H is the height of the room;
• 12 is a coefficient indicating the cycles of air replacement in the room.

For example:

• room area - 12 m 2;
• height - 2.7 m;

We substitute the values ​​into the formula: Q = 12 * 2.7 * 12 = 388.8 m3. Based on this calculation, the device will produce this volume only using maximum performance. It will not withstand such a regime for a long time and may fail.

Thus, a small power reserve for a cooker hood, facilitating the operation of the appliance. And for you, the opportunity is created to turn on the maximum mode only during times of high smoke content in the room, for example, on the eve of the holidays, when a large number of dishes are being prepared.

It should be noted that all these calculations for the volume of air exchange have average indicators, since this does not take into account different nuances:

• type of hob;
• layout of the premises.

Hob type

The type of stove determines how much pollutants can be released into the air during cooking. And its renewal, accordingly, should occur more or less often. The refresh rate must also be changed. The calculation of the power for the kitchen differs from the standard one, since no combustion products get into the air, except for fumes from the food being cooked. The coefficient for such plates can be increased from 12 to 15, and the formula will look like this: Q = S * H ​​* 15.

Cooker hood over electric stove

When you are going, the coefficient should be increased to 20. This is done so that in addition to the fumes from the food being cooked, a large amount of harmful products of gas combustion enters the atmosphere. In this case, the formula is written as: Q = S * H ​​* 20.

Hood over the gas stove

Hood type

The units differ in operating mode, namely, where the passed air is discharged. There are 2 types of devices:

• ventilation;
• recirculating.

Device implies connecting it to ventilation duct in the house, to remove waste gases outside. But before calculating the power, the bandwidth of the channel must be taken into account. If the house is old and the ventilation shaft is clogged, then although you buy a powerful hood (according to calculations), it will not be able to remove the air at full strength. And to the neighbors in the riser, exhaust gases from your kitchen will be blown into the room. In such cases, you can do separate exit for ventilation to the outside by making a hole in the wall.

Devices contains in the design filter system and does not require connection to a ventilation shaft. In most cases, cleaning takes place in 2 stages. First, the first filter absorbs large particles: steam, grease and fumes. Then the air passes through a charcoal filter, which removes all odors, and flows back into the room.

Filters can create some resistance when pumping, which must also be taken into account when calculating the hood capacity. The recommended increase in this value for such devices is approximately 30 - 40%.

Room layout

When calculating the ventilation capacity, the kitchen layout should be taken into account. If, for example, an arch is installed instead of a door, or you are used to not closing the door, then the volume of the adjacent room should also be taken into account in the calculations.

If the kitchen is combined with the dining room or living room, the requirements for calculating the performance of the device increase significantly, due to the rapid spread of odors that must be effectively removed.

Noise level

Now that, using the above recommendations, you have made calculations of the required hood power for your kitchen, you should think about the noise that it will emit. In a store, when choosing a device, you are unlikely to be able to assess the noise of the device due to the large size of the room or other noises in the sales area. Correctly assessing this indicator will help instruction supplied with the unit.

The more powerful the device, the stronger the sound it makes.

In the instructions, you should look at the sound parameters at maximum load and in the normal mode of the device. If the noise level is between 30 and 45 decibels in standard mode, then the operation of the device will not cause you any discomfort. Such hoods can be called practically. When working at maximum, the sound should not exceed 55 decibels. If this figure is exceeded, then such a device can only be suitable for large rooms. Otherwise, loud sound will be unpleasant.

By following the above recommendations, you will be able to choose the right hood power for your kitchen. And this, in turn, will contribute to the creation of a pleasant indoor climate and well-being during cooking.

Properly calculated power plays a significant role when purchasing a device. Specific smells during cooking and frying food, evaporation, fumes, smoke - all this is removed by means of this device. However, this is possible only when its performance meets the required characteristics.

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

What is the power calculation for?

The engine performance will determine how much of the exhaust air the hood can replace in an hour and 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 meets the conditions of SNiP. Having selected and installed the hood of the required power, the costs for it are compensated over time by saving detergents.

Factors Affecting Power Calculation

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

Q = s × h × 12.

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

In addition to the kitchen area, the following parameters must be taken into account:

• family composition (the consumption of clean air must comply with sanitary standards for one person);
• frequency of cooking;
• what dishes are being 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 affects the performance of the hood. The type of stove affects the amount of waste in the form of scale, burning, entering the air at the time of frying meat, boiling borscht, or healthy food with only vegetables. In this case, 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 the cooking food. As a rule, the air exchange rate for these electric stoves is increased during calculations from 12 to 15, 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-on and so on enter the air space above the stove. Here the formula for calculating performance will be different: S × H × 20.
2. It would be wrong to say unequivocally that if there is a 65 cm hob, the hood should be more efficient than with a smaller 55 cm stove.However, logically, this can be assumed, because large hoods process air mass from 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 parameters of the device. It is much easier to calculate the power of the hood if the main aspects are taken into account.

Kitchen location

When calculating the performance of a kitchen hood, the type, area and its isolation are taken into account. This 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, you need to take into account these additional parameters in the adjacent room, thereby completely providing fresh air to your household.

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

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

The higher the power of the cooker hood, the faster the air above the stove in the kitchen is cleaned. The performance can be quickly calculated from the table below.

Exhaust capacity

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 takes place no more than two or three times a day and in small volumes. For more frequent "cooking" it is better to use a classic hood with a capacity of 600 m³ / h.

On a note! The productivity of the device is indicated in m³ / h. It is sometimes called power. However, this value cannot be used as power consumption, which is expressed in watts (W).

Performance must comply with SNiP standards. Air change occurs approximately 10-12 times per hour of operation. For calculations, as a rule, they take the number 12. If households often smoke in the kitchen, then the performance of the unit increases by 20-30%.

Power calculation

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

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 air volumes in a room, up to 40 m³. With the help of it, the smallest extraction power is determined. In practice, this value can change as it is influenced by other aspects as well: the type of hob and air circulation, the composition of the family and the location of the kitchen.

For an illustrative example, we will give a calculation of the performance of a 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 capacity of the hood, it is necessary to substitute the input digital values ​​into the formula:

(3 × 4) × 2.8 × 12 × 1.5 = 604.8 m³ / h

Consequently, calculations have shown 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 for

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

Hood type

Appliances are divided according to the principle of operation, and more specifically, by the method of diverting the air flow from the hob.

There are two types of exhaust devices:

• flowing;
• recirculating.

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

Such modes are chosen at the will of the owner, in general, the second option is convenient to use in winter, so as not to cool the kitchen with the flow of cold air when replacing. 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 it deflects 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. Alternatively, you can 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 duct for ventilation. In these hoods, the air mass is purified in two stages. First, grease, burning and scale particles are removed with mesh filter elements.

Then the air mass undergoes a second cleaning through activated carbon, after which all unpleasant odors disappear and then the air returns back to the kitchen. During the operation of the unit, filters provide resistance to air circulation, and this must also be taken into account when calculating the performance. It is recommended to increase the indicator 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 different 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 considered to be a level from 30 to 45 dB. In the case when the digital value of the hood is higher, then its operation will be loud. The more massive the walls of the hood of the hood, the quieter it will work, since all sounds will be absorbed inside the hood.

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 a lower power are built in, which significantly affects the overall noise level downward.

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

1. Performance. The more powerful the apparatus, the more efficiently it will set the air in motion. Therefore, it will generate more noise during this operation. Therefore, you should not purchase a hood with a power exceeding the calculated one for a given room.
2. The number of modes of operation. Choose a cooker hood with several modes. This can reduce the noise by setting the process to a minimum. 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 timely change the carbon filter elements of the second stage, since they also significantly increase the noise level in a dirty state.

Finally

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

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

Exhaust power calculator

Somewhat earlier, such a factor influencing the choice as the noise emitted by the exhaust system was mentioned. Do 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 atmosphere.

According to the facts, the comfortable threshold of noise in the room is no more than 30 decibels (dB), this is the so-called background noise - the distant rumble of engines of cars passing along the street, bird chirping outside the window, the murmur of water in 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. Compared to household noise, this is tantamount to a whisper 5 meters away, a conversation 10 meters away and a quiet conversation 3 meters away, respectively. Accordingly, the 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 renewed, 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 multiply the result by those 12 complete air purifications. However, this number of airings is usually designed for the maximum load of the hood, that is, this will mean an outrageous 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 the hood is largely influenced by the type of hob, due to the different amounts of combustion products emitted into the air. So, in the electric panel they are completely absent, as well as in the induction one, and in the gas one they take place, 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 20 times per hour. It is logical that if the doorway is devoid of a closing sash and turned into an arch, the capacity should be increased due to the spread of odors and combustion products, and for the same surfaces it will already be in the range of 600 and 800 m 3 / h, respectively.

Unlike a kitchen, a car space 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 calculating the hood, you need to decide what kind of vehicle and in what quantity you will put there. Exhaust from a passenger car and a truck differ 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 rates established by ABOK, it is necessary to provide an air flow of 180 cubic meters per hour for one passenger car.

It is not recommended to make many bends, since the more there are, the louder the exhaust system noise. In addition, each elbow reduces ventilation efficiency by approximately 10%. In order for the air drawn by the turbine to be replenished at the same rate, several inlets can be made by equipping them with fans that work for drawing. 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 rodents from entering.

The obligatory calculation of the hood for the kitchen is an important condition for its functionality and a comfortable microclimate in the room. However, it will be difficult to perform calculations even in an approximate version without knowing some of the details.

Like other options for ventilation equipment, the purpose of kitchen exhaust equipment is to remove steam and smoke, microparticles of fat and soot, and other harmful elements from the room. Standard ventilation is not enough for this. And housewives have to spend a lot of effort to clean the stove and tiles adjacent to the cooking area.

To facilitate cleaning and maintain a favorable microclimate, the hood should be several centimeters larger than the hob. In addition, the room air must be renewed 12 times within an hour. It is also imperative to keep the distance between the stove and the hood.

Secondary, from a technical point of view, but an important aesthetic point is the correspondence of the design of the selected sample to the overall design of the kitchen. Today you can choose:

1. Flat models with and without inclination. The smallest option for small kitchens.
2. Dome, shaped like a pyramid or hemisphere. Most powerful and suitable for large spaces.
3. Built into furniture, niche or wall.

T-shaped, telescopic, island and corner variations can be added to this list.

According to the principle of operation, manufacturers produce ventilation of the exhaust type and working according to a recirculation scheme. The former require a constant flow of air. They are cheaper, but less effective at cleaning the air. The latter are independent of the external atmosphere, effectively remove pollution, but require regular renewal of carbon filters, which increases their maintenance costs.

Power calculation formula

The calculation of the performance of a conventional hood is carried out taking into account the diameter of the exhaust hole. The ventilation ducts in apartment buildings have a maximum cross-section of up to 125 mm. Their throughput per hour is about 400 cubic meters of air. With such constraints, equipment with great capabilities may be useless. For recirculation models, area is more important.

P = (a × b) × h × 12 × 1.3

In this expression:

• P - productivity;
• a * b - the area of ​​the room;
• h - height from floor to ceiling;
• 12 - coefficient of air change within an hour;
• 1.3 - coefficient of error, taking into account additional factors (number of storeys, length and degree of mine pollution, number of bends in the channel).

Using the formula, you can calculate the indicator for optimal operating conditions, when the electric stove is working, all windows and doors are closed, and the layout is strictly rectangular.

With standard dimensions of the room, when the area and height of the ceiling are known, and the conditions for using the equipment are the same, the level of performance can be found in the table with ready-made data:




It is better to add another 15-20% of the reserve to the results obtained for a possible increase in the load on the device.

Consideration of additional factors

To choose a hood for the kitchen, in addition to performance and power, you need to take into account the number of family members, cooking frequency, layout, type of hob and other factors.

Family size

The throughput of the plant is in the range from 200 to 600 m³ / h. A device with minimum parameters will be enough for two people. A family of 3-4 people needs to take a model with an indicator of up to 400 m³ / h. It is better for large families to choose the maximum indicators.

There are also models with enhanced parameters up to 1000 m³ / h, but the price is very high.

Cooking frequency

The daily cooking volumes are calculated in a similar way. A monotonous diet and infrequent visits to the kitchen do not require particularly powerful installations. An increase to average will be needed with a more varied menu and occasional cooking. And for those who love to cook and spend a lot of time at the stove, it is better to choose a model with increased parameters.

The longer the food is cooked, the faster the air exchange should take place. To maximize this process, you need equipment with maximum performance from 600 to 1000 m³ / h.

Features of the layout

Insulation and layout are another important factor. It's one thing when the kitchen is separated from the rest of the rooms by a door and has a geometrically correct layout. The situation is different with an open plan, where there are an abundance of irregular lines. The latter option is more expensive in terms of power. In this case, when calculating, you need to take into account the dimensions of the adjacent room.

The installation of an electric stove can be successfully combined with the choice of a low-power hood. If a gas stove is installed, increase the preset air exchange coefficient to 20. This will take into account the accumulation of gas combustion waste in the air.

Air pollution level

The choice of technical parameters should take into account the likelihood of food scorching and smoke generation. An excessively large power reserve of flow-through equipment will lead to increased noise. The norm is considered to be noise from 30 to 45 dB, at maximum modes it can be increased to 55. Anything higher causes discomfort.




Consideration of performance parameters

The calculation of the power level for the exhaust and recirculation models will be different. Design features affect the installation of equipment, operating rules, and hence the requirements for technical parameters.

Discharge or flow devices

This type is equipped with an air duct with a built-in fan. The connection is made directly to the ventilation hole, through which contamination is removed outside the house or apartment. When choosing a model for technical characteristics, you need to consider:

• the total length of the exhaust duct, for each meter of which the loss of throughput is about 10%;
• the number of bends, each of them takes the same percentage of power;
• bend angle - with one 90 ° right angle, the loss will be greater than with two 45 ° angles.

Before installation, check the condition of the ventilation shaft to which you are planning to connect. If there are blockages in it, you will have to spend time cleaning. Otherwise, even compliance with the performance standard will not give the expected result. In an apartment building, this can lead to the overflow of polluted air into the neighboring apartment.

Also, the installation of exhaust equipment, subject to all requirements, often disrupts natural ventilation and provokes the same consequences. Therefore, in high-rise buildings, flow models are recommended to be connected to a separate outlet with appropriate calculations. Ideally - to a circular duct with a lattice air intake at the outlet and a non-return valve.

Recirculation models

Units with this principle of operation are not connected to ventilation and operate autonomously. The purification system has two levels of filtration. In the first rough stage, large particles of grease and fumes are removed from the atmosphere. At the second stage, there is a fine cleaning of odors. After that, the air returns to the room. Filter resistance reduces technical characteristics by 30-40%.

But experts say modern filter elements are thin enough to allow flow to flow freely through them. The specified throughput is maintained until replacement. It is not the filter itself that clogs with fat, but the outer grill, which must be washed periodically.