When planning a repair or renovation of the kitchen, in addition to the furniture set, refrigerator, sink and dishwasher should provide a place for exhaust. The hood performs an important task and must not only be properly selected, but also installed. We will advise how not to get lost in the jungle of proposals and choose a model that will suit your needs, how to plan the ventilation, how to choose an air duct for exhaust.
More and more kitchens are equipped with an exhaust hood. In some houses it is also necessary, like a stove. With it, you can quickly get rid of the smell of fried fish, burnt porridge or vinegar marinade. Without it, on the kitchen cabinets accumulate particles of fat, which fly through the kitchen along with the steam from cooking. Effective hood removes excess moisture from the apartment and is an integral part of the modern kitchen, in addition, if it is coordinated with the interior, it also decorates the room.
The market is flooded with various types of kitchen hoods, among which it is not difficult to get lost. When buying, we advise you to follow certain rules. First of all, you should answer two questions:
By answering these questions, you can outline the range of products that are worth paying attention to.
The hood is most often connected to the ventilation duct. Then it works in an open system. If it is not connected to ventilation, then it works in a closed system, as an absorber of pollution from the air using a filter.
By design, hoods can be:
Most of the hoods are connected to the ventilation ducts, which are in almost every kitchen and are located above the kitchen stove.
Typically, hoods are placed on the wall above the stove and can be placed separately, or be embedded in a kitchen wall cabinet. There are also modern solutions, such as exhaust hoods built into the worktop, which are used in rooms with high ceilings and in other special cases. However, this option is very expensive.
In each house should be equipped with a ventilation system. However, it is not always possible to connect this device to it, for example, in an apartment building (usually a multi-storey building) equipped with a collective duct. In addition, it does not connect to natural ventilation if the house has a wood burning fireplace, a coal boiler, or other devices with a flue connection (for example, a gas stove, a gas boiler). There are models of hoods that do not require an air duct and operate in a closed loop, using special filters.
The hood is connected to the ventilation duct with an air duct.She collects air around the cooker and blows it into the ventilation. A duct is connected to the ventilation, which usually has a circular cross-section and a diameter of 125 or 150 mm. Some manufacturers offer pipes with a rectangular cross section.
An exhaust hood for a kitchen with an air duct works properly only if the correct amount of fresh air enters the room and optimal conditions are created for its flow. Sometimes it’s enough just to open a window or a window. It is also possible, as is sometimes practiced, to make small openings in the balcony door of the kitchen to allow fresh air to flow into the room. The devices can be equipped with valves that prevent the return of vapor to the room, and partitions that protect against the return of condensed steam.
The device can be equipped with one or two engines. Their power ranges from 18 to 200 watts.
The fan-powered fan sucks air above the stove and feeds it through the air duct into the ventilation duct.The fan can take in air at the bottom, on both sides (bottom and front).
There are also versions that are equipped with two engines, sucking air even from four sides, thereby increasing the efficiency of work.
The device will not cause discomfort if the level of sound that it makes during operation is low, especially if the device does not work at full speed. The loudest models when working with maximum power make sounds up to 72 dB, which is certainly not very comfortable for hearing. For comparison, the conversation between two people creates a noise of 50 dB, the sound of a sewing machine - 70 dB, a traditional vacuum cleaner - 72 dB. Some companies use silencers in their products, which significantly reduces work noise.
Performance can vary greatly. It is higher, the more air can change per unit of time. The simplest model replaces just over 200 m³ of air per hour, and for large kitchens, you can choose models with an air exchange rate of up to 800 m³ per hour.
The model must be selected so that within an hour it can replace the air in the room six times. On the other hand, the wrong opinion is that the greater the performance, the better.For example, in kitchens where cooking is carried out on gas stoves, models with excessively high power, which replace indoor air more than 12 times per hour, should not be used, since such exhaust can worsen the conditions for gas combustion.
Performance must be consistent with the size of the room in which the device will be installed. Only properly adjusted performance will ensure effective removal of odors and moisture from the kitchen.
In order to calculate the necessary power of the device for the room, its cubic capacity (that is, the area multiplied by the height of the walls) is multiplied by six.
Thus, the easiest way to choose the optimum extraction performance (measured in m³ / h) is a very simple calculation:
kitchen volume (m³) * 6
For example, if your kitchen has an area of 12 m² and a ceiling height of 3 m, then the minimum exhaust performance is calculated as follows:
12 x 3 x 6 = 216 m³ / h
It should be noted that the value of performance and exhaust efficiency may vary under certain conditions.As a rule, the hood is connected to a pipe-duct up to 2 meters in length with a single bend of 90 degrees.
The exhaust and the ventilation system to which it is attached create resistance to the air flowing through them. The greater the path the air must travel, and the more obstacles in the form of bends, the lower the actual performance of the device. Therefore, we must strive to make this “path” as short and simple as possible.
A large room or an open kitchen requires a ventilation duct with a minimum diameter of 150 mm (most hoods have an outlet of this diameter), and if you want to install an additional engine, then 180 mm or more.
Air ducts to the kitchen hood with a diameter below 150 mm reduce the efficiency of the device and raise the noise level of the air flow.
When installing the device, conditions must be created to reduce the performance loss that may be caused by improper connection or reduction of the duct cross-section.
Each bend of the duct pipe by 90 degrees and each additional meter of pipe significantly reduce the performance of the device.Installing a carbon filter reduces efficiency by about 25-30 percent.
Metal filters affect the efficiency and performance of the hood, but without them, the device cannot be operated, as fatty particles penetrating into the interior are deposited on the inside of the device, on the engine and air duct. Over time, this can lead to poor engine performance, increased noise and, ultimately, engine failure. Efficiency of standard metal filters: from 40 to 80%. The 12-ply structure and sealing tapes can increase efficiency up to 95%.
After connecting the hood with the air duct, make sure that the right amount of fresh air will flow into the room.
Also important is the direction in which the air flows. Avoid creating drafts in which air moves along the diagonal of a room.