The main task of the kitchen hood is to ensure that the air is cleaned from unpleasant odors and to protect the furniture from plaque of grease and soot. Therefore, when choosing a kitchen device, it is important to pay attention not only to the brand and form, but primarily to the technical characteristics. The main parameters are power and performance.
Types of hoods, power and methods for its determination will be considered further.
Types of hoods for the kitchen
The most popular hoods by the principle of operation:
By design, hoods are:
- flat;
- recessed;
- domed;
- desktop.
Consider them in more detail, and also determine how much power the hood should be.
Types of hoods for the kitchen
Flat hoods are installed directly on the wall above the stove. Air purification is carried out using a fan and filters. Such devices are used in kitchens where it is difficult to exit air into the ventilation. The price of the equipment is quite loyal, and the design is attractive.
Built-in hoods are installed in a hanging cabinet above the stove. This is necessary to hide the exhaust pipe. Such systems are equipped with a pull-out panel or are fully integrated. The first version of the device is visible only during cooking. The rest of the time is hidden in furniture. Built-in hoods are better in quality than flat ones, but the price is also higher.
Dome hoods can be metal with wood or glass trim or all-metal. Suitable for any interior, as they are characterized by a wide range of colors, shapes and sizes. Such equipment is distinguished by a number of certain technical parameters and, in addition, does not need to replace filters.
If there is no possibility to use suspended hoods, use tabletops. This type of device is integrated into the hob as an optional module. Equip them between the stove and grill. Due to the close location to the source of contaminated air, its high-quality cleaning occurs.
Flowing kitchen hoods
The principle of operation of the flow hood is as follows:
- Under the influence of the blades of an electric motor, hot polluted air rises up the air duct and is discharged into the ventilation passages.
- Air passes through a special metal filter. It is on it that all particles of soot, soot and drops of fat suspended in the air settle.
- When using this type of device, it is rarely possible to install additional filters (for example, against odors). The reason for this: the air that passed through the duct does not enter the room back.
- Efficiency depends on the rated exhaust power provided by the internal engine and the condition of the building duct. If the ventilation ducts are clogged, then most of the power will be lost.
An important point. So that the grease filter does not create additional resistance to air flow, it should be periodically cleaned of accumulated contaminants. Otherwise, even the greatest power of the kitchen hood will be insufficient to cope with the removal of dirty air.
Circulation hoods for the kitchen
Hoods of this type work independently of the ventilation system of the building. This distinguishes them from flowing devices. The principle of operation of the hood is as follows:
- An electric fan pushes air into the hood.
- Soot, soot and drops of fat settle on the grease filter when air passes through it.
- Air passes through a charcoal filter under pressure. The main function of this filter is to eliminate unpleasant odors.
- Air after passing through double filtration enters the room again.
Hoods with a charcoal filter are perfect for private homes and rooms that have poor ventilation systems.
Cooker hood dimensions
The overall performance of the hood for the kitchen is also affected by its dimensions:
- The best option is when the hood area is equal to or greater than the area of the hob (gas stove). In this case, the power of the device for the kitchen will be enough to fully capture all the fumes that rise above the stove.
- In industrial production, the standard size of the hoods most often corresponds to the size of the hobs and has a width of 50 or 60 cm.
- A more expensive option is equipment from 80 cm to 1 m in size. The extraction power is enough to clean the air above a large stove. Such devices are sometimes called professional.
- The power of the exhaust hood, made by yourself, depends on the installed engine, the configuration of the dome and duct of the exhaust device. Therefore, before making the hood, you need to lay a small margin in size in the project.
Norms and Requirements
Mandatory installation of the hood is provided for workshops for cooking and bakeries. But for apartments and private houses, the hood is installed at the request of the owners. According to building codes, they are equipped with forced or natural ventilation. But usually even for small kitchens this is not enough.
According to SNiP, ventilation equipment (including a hood for the kitchen), must completely renew the air in the room several times in an hour. For kitchens in residential buildings, this amount is 10-15 times. This value depends on the type of stove, the operation mode of the fan and other factors. To simplify the calculations, this coefficient is taken equal to 12.
Noise level
Each hood model should indicate how much noise it produces in decibels. However, it is not always clear to an ignorant person what will happen in practice. In most cases, modern hoods produce about 50 dB. For comparison: the rustling of pages is 20 dB, and the conversation at a distance of a meter is 60 dB.
Usually during the day the hood is used in low and medium intensity mode. Therefore, when choosing a device, it is important to pay attention to these indicators.
Recently, hoods with a perimetric suction system are gaining more and more popularity. This technology is noteworthy in that the intake air from the central part is redirected to the external perimeter of the device. This reduces the load on the engine and, consequently, the level of noise produced.
Performance
Hood performance is the volume of air that it purifies in an hour. The more air it can pump, the greater should be the power of the exhaust fan.
The exhaust power is measured in cubic meters of air per hour (m 3 / h).
The minimum productivity value is about 200-300 m 3 / h. Such hoods are inexpensive, but they do not work very well with the job either. Suitable for those who cook extremely rarely.
In the case of daily cooking, the best option would be a standard (about 600 m 3 / h) or enhanced hood. Reinforced devices have high power (up to 1000 m 3 / h), but their price is corresponding.
It is worth saying that different manufacturers indicate the power of their devices, using different calculation parameters.
- Sometimes indicated "naked" turbine power.
- Some manufacturers prescribe real indicators obtained in practice.
- Large manufacturers indicate several values and indications. Data obtained through various tests.
Calculation of hood power
When in doubt when choosing a hood, it is worthwhile to make some calculations.
What power hoods for the kitchen are needed can be found in the following formula:
Q = 12 * S * H * 1.3, where:
12 - air exchange rate per hour (as mentioned above, this is an average indicator).
S is the area of the kitchen.
H is the height of the kitchen.
1.3 - minimum margin ratio. It is needed to take into account the number of storeys of the building, the length and degree of contamination of the ventilation shaft, as well as the length and bends of the duct, which could result in loss of device performance.
The value obtained in the end will be the minimum required power for extracting to a particular kitchen.
Additional factors in the calculation. Minimum Performance Examples
Above is the simplest formula for calculating the power of the hood. But still it’s worth making some clarifications to it:
- To begin with, the coefficient is 12. This is an average indicator, and it does not provide any power reserve for emergency cases.
- In addition, the same indicator also depends on the hob. For example, for electronic hobs, the value should be 15, and for gas stoves - 20.
- Another point is the area. If the kitchen is isolated from other rooms by doors and walls, then this calculation of the area is enough. If there are arches or a combination of rooms, then you need to add the area of the room adjacent to the kitchen.
For example, a few indicative indicators:
- for a kitchen with an area of 6 m 2 and a ceiling height of 3 m, the minimum exhaust power is 281 m 3 / h;
- if the kitchen area is 11 m 2 and the ceiling height is 4 m, then the indicator should be from 515 m 3 / h;
- with a kitchen area of 15 m 2 with a ceiling height of 2.5 m, the minimum power is 585 m 3 / h;
- for a kitchen with an area of 7 m 2 and ceilings of 3 m and a kitchen with an area of 6 m 2 and ceilings of 3.5 m, the power is the same - 328 m 3 / h.
Useful features
In addition to the main task of air purification, modern hoods have a number of additional functions.
The lighting of the device does not affect the operation of the hood, but at the same time it is a convenient and necessary function. For lighting, use built-in LED lamps, incandescent or halogen. The most economical option is LED and halogen lamps. Usually they are covered with a diffusing or protective frosted glass. And replacing the lamps is not difficult.
The hood control also has several schemes. Namely:
- push-button;
- slider-slider;
- sensory-electronic.
The button option is now becoming less common. Using the control panel, you can adjust the engine operating mode, performance, backlight, turn on or off the ultraviolet or quartz disinfection lamp (if provided). There are also models of hoods that have a clock and a timer.
Finally
A cooker hood not only complements the design of the kitchen, but also is an excellent helper in the fight for clean air. Knowing what kind of hood power is needed, the choice will be much easier. In addition, correctly calculated performance will allow you to get the most high-quality operation of the device. Therefore, the calculations must be approached with all responsibility.