Ventilation plant "Bastion" offers its customers high-quality products manufactured just in time. The company is one of the market leaders not only in St. Petersburg, but throughout Russia.
In this article we will talk about the use of exhaust hoods in various conditions.
Principle of operation and varieties
In the kitchen of a modern housewife and in catering establishments, an exhaust ventilation hood or dome is installed. Its main task is to purify the air of the room from high humidity, odors, various impurities, the occurrence of which is associated with the cooking process.
The exhaust hood is an integral part of a high-quality ventilation system in the premises. Installation takes place above sources of high temperature, in particular, over stoves, hobs, open flames. With the help of the dome, humid hot air, unpleasant odors, as well as soot, grease, soot, dust, and chemicals are removed.
Purification of air from harmful impurities is also necessary in laboratories, chemical and industrial production, etc., where the production process occurs with the release of harmful substances into the space, which can harm workers and the environment as a whole.
The umbrella is a dome-shaped structure, hence the second name - the dome. Connected to the ventilation system by an air duct. There are central (island) and wall, depending on the installation location.
Installation of wall-mounted units is carried out directly on the wall. With a large weight, additional brackets are used for fixing. Central devices are installed directly above the work surface, without contact with the walls. Island umbrellas have a large capacity.
A modern dome is not only a complex device, but also an element of decor. Factory facilities allow the production of umbrellas in accordance with the general interior of the room.
There is no fundamental difference in structure between domestic ventilation domes used in private households and industrial ones, they are distinguished only by size and power characteristics. Umbrellas used indoors have a common device:
- Grease filter. It can be mesh (made from a mesh with small cells) and labyrinth (a plate with grooves through which condensed fat enters a special compartment). The first type of filter is cost-effective, it is installed only in a horizontal position, it can be additionally equipped with a spark arresting mesh, but it requires frequent cleaning. The labyrinth grease trap can only be installed in an inclined position and does not require frequent washing.
- Sparkling mesh. An obligatory element when installing ventilation domes over sources of open fire, for example, over barbecues, grills.
- Pendants. Part of the mounting system that allows you to mount an umbrella on a wall or ceiling with the correct weight distribution.
- Turbines. The equipment is designed to stimulate the movement of air masses from the room. During installation, the center of the work surface and the dome must be correctly determined in order to achieve maximum efficiency. The cross section of the inlet of the exhaust hood must exceed the dimensions of the slab or other equipment over which it is suspended. The suspension height varies from 0.7 to 1.1 meters.
When choosing a manufacturer of an exhaust dome, give preference to domestic factories, so you can save your budget, and the quality of modern products from a reliable seller is confirmed by certificates and quality control.
The root of construction troubles is hidden in the details. Neglecting small details, the owner of private housing inflates the family budget inefficiently with repair costs. But if the owner treats the house as a whole organism in which everything is interconnected, his money does not fly out the pipe, and the costs are limited to scheduled maintenance. Improper installation of protective devices on the chimney provokes losses - both financial and human.
Installing an umbrella on the chimney helps to maintain the heating system in optimal mode, prevent premature aging of the chimney, and improve air circulation in the house.
Caps and caps on pipes are designed for the following purposes:
- close the ventilation duct, protecting it from rain, snow and dirt. The lack of protection can lead to the accumulation of a large amount of water in the chimney, which contributes to a decrease in draft and, accordingly, a drop in the efficiency of the heating system;
- protect the pipe material from damage, removing accumulated condensate due to the presence of special grooves;
- do not allow insects and birds to fall into the pipe, serve as an obstacle for leaves and branches from trees;
- perform a decorative function. They give the roof a complete look, especially if the design contains elements of artistic forging.
Note! Using an umbrella, you can solve one of the problems of dampness in a house or bath. If the pipe is open to all winds and rains, the moisture that has got into it penetrates into the premises. As a result, the walls and floors are affected by the fungus, an unpleasant smell appears in the air.
Some types of caps have a design that creates a rarefied environment in the upper part of the pipe. Due to this, an improvement in draft in the chimney is achieved, excess moisture, exhaust air and combustion products are removed faster.
Steam and fumes fill your kitchen while cooking, and the ceiling above the gas stove is covered with layers of grease. The reason is either the ventilation umbrella is incorrectly selected according to the parameters. For a successful solution to the problem, we suggest that you familiarize yourself with the types of engineering structures, installation rules, as well as the feature of choosing a model according to parameters.
Any cleaners and humidifiers will not cope with the soot formed during cooking. Above a gas or electric stove, you need a powerful hood with a dome, the dimensions of which exceed the area of \u200b\u200bthe hob. This role is played by an umbrella. The device does not occupy a useful kitchen space, being in a suspended state.
Exhaust domes are installed above household stoves, in food industry shops, and chemical laboratories. Umbrellas are used wherever there is a risk of air pollution with harmful impurities. Install hoods over a source of high humidity and temperature.
Depending on the model, the exhaust device is equipped with the following elements:
- An electric fan is installed in the ventilation hole of the dome to force the exhaust of contaminated vapors. The presence of turbines is typical for all modern hoods.
- Filter for trapping fat impurities.
- Spark arrestor. The mesh is completed with exhaust products installed above an open source of fire.
- Backlight. For convenience of work under a dome lamps are built in in the case.
- Mounting fasteners.
The umbrella works on the principle of forced ventilation. Dirty air collects under the dome. A rotating turbine sucks it in and discharges it through an air duct to the street. The filter system traps grease and soot impurities, preventing them from accumulating on the fan blades.
Types of umbrellas
According to the principle of operation, the devices are divided into two groups:
- Exhaust models have only one function aimed at removing dirty air from the room.
- Supply and exhaust models perform two functions: they remove dirty vaporous masses, and also provide an influx of clean air from the street.
Air-conditioning hoods are placed indoors, where the flow of oxygen is limited. The amount of fresh air supplied is one third less than the intake of dirty air masses.
Exhaust devices are divided into three groups according to the type of design:
- A feature of wall-mounted exhaust hoods is the presence of one row of filters that trap fat. The dome is attached to the wall above the hob or other equipment.
- Island models are equipped with two rows of filters. High-performance hoods are suspended with cables or chains from the ceiling. They have domes over free-standing devices of large dimensions in any part of the room. Rectangular models can be hung against the wall.
- Umbrellas-transitions are installed over an open source of fire. In everyday life they are hung over barbecues. The dome is necessarily completed with a spark-extinguishing mesh.
All models of umbrellas in cross section have the shape of a trapezoid, rectangle or triangle. According to the purpose of the hood, there are household and industrial ones.
Industrial
Umbrellas for industrial ventilation systems are characterized by large dimensions, as well as the presence of a powerful fan. The set of filters is equipped with special traps. The settled impurities of fat from them flow into the glass.
Periodically, the container requires cleaning, followed by washing with detergent.
household
Household hoods are equipped with disposable paper or fiber filters. Umbrellas are usually produced wall-mounted, since in the kitchen the stove is most often located against the wall.
The appliances are equipped with a less powerful fan, and the dimensions are calculated for the area of the cooking surface of the household stove.
What is the difference
The main difference between domestic and industrial hoods is in performance, dimensions, as well as the filters used. The principle of operation is the same.
For spacious kitchens, household island appliances are produced that do not visually differ from industrial models.
Types
According to the type of installation, ventilation elements are divided into built-in, flat, and domed structures.
Embedded
Built-in devices are distinguished by quiet operation. Install the hood directly above the hob. Work is carried out in the mode of circulation and air removal.
Flat
Flat-type exhaust devices are economical and lack an outlet pipe for connecting to an air duct.
Air purification occurs due to circulation through the filter. The disadvantage of the model is noisy operation, as well as the need for frequent replacement of filters.
dome
Dome-type models are available wall and island. Work is carried out in the mode of removal and air circulation. Hoods have high performance, are attached to the wall or suspended from the ceiling.
What are umbrellas made of?
On the inner surfaces of the dome, not only fats settle, but also steam, chemicals, and other aggressive components that cause corrosion. In addition, there is a destructive effect of high temperatures. Only metal can withstand such conditions.
Industrial, as well as expensive household models are made of stainless steel.
The metal is considered heat-resistant, resistant to corrosion and acids. Cheap household appliances are made of galvanized or ordinary tin, followed by painting. There are aluminum products.
How to choose an umbrella
To choose the right umbrella, three important factors are taken into account:
- The shape of the ventilation product is selected taking into account the parameters of the room, the dimensions of the plate, as well as its location. They think over the optimal method of fastening, which is affected by the height of the ceilings.
- Size is one of the important parameters that affect the degree of indoor air purification. The dimensions of the hood must be at least 10 cm larger than the dimensions of the hob. If the stove is not located near the wall, the umbrella overhang is increased to 20 cm.
- The main parameter responsible for the efficiency of work is productivity. To select a product with optimal air flow, take into account the height and length of the umbrella, as well as the cross section of the filters. When comparing hoods of the same size, the performance will be higher for a product with a higher dome height.
When choosing an umbrella, pay attention to the diameter and number of connected air ducts. For household models, one output is enough. Four air ducts are connected to hoods with a length of 160 cm or more: two for the exhaust and two for the inflow.
How to calculate power
The hoods must carry out ten air changes. In production, complex formulas are used to calculate power. Household models in the kitchen are not able to change the air ten times. The calculation of the umbrella power is carried out according to the parameters of the plate.
For example, there is a gas stove with four burners. Data is taken from the data sheet of the device. You need to find out the power of each burner, and add all the values. Let's say we get an example: 1.9+1.9+1.0+3.5=8.3 kW. The result indicates the heat output of the gas stove. It can be assumed that a maximum of three burners will always work, but it is undesirable to make a margin down. The power of the thermal parameters of the stove and the hood are the same, which means that an umbrella rated for 8.3 kW is required.
What filters are needed
A reusable and disposable filter is installed on the exhaust hood. By design, it is multi-layer and single-layer. In household models, a disposable filter is used to trap fat from paper, synthetic winterizer or acrylic. An aluminum mesh spark arrester serves as protection against an open source of fire.
Industrial products are equipped with a reusable filter, which is washed in water with detergent.
Do-it-yourself installation
Do-it-yourself installation of an umbrella is carried out in four ways, which depends on the design of the product:
- wall models are fixed with anchors to the wall, through technological holes on the umbrella body;
- wall and island models can be fixed to the ceiling with a stud and collet;
- island and rectangular wall models are fixed to the ceiling with chains or cables, having previously installed the anchor;
- installation on a support frame provides for the manufacture of a metal structure securely fixed above the hob.
The fourth installation method is considered the most difficult. The frame is welded in the shape of an umbrella. The structure is mounted on support legs with mounting plates welded from below and fixed with anchors to the floor.
At what height to mount
The quality of air exchange depends on the height of the umbrella above the hob. The parameters are displayed in the umbrella manual. Typically, household models are removed from a gas stove to a height of 80 cm, and from an electric stove - at least 60 cm.
There are several traditional ways installation of wall and island ventilation hoods, which are designed to remove heat, smoke, moisture, odors from technological equipment installed in catering establishments, cafes, bars and restaurants.
The first way to install the exhaust hood
The first way (the easiest one) is installation of exhaust hoods to the wall with anchors. Depending on the length of the hood, two or three holes are drilled symmetrically in the rear vertical wall of the exhaust hood. Through the enlarged washers with anchors, the exhaust hood is attracted and fixed to the wall. The wall in this case should be solid and even, at least brickwork. If the umbrella has a long reach (more than 1000 mm), it is recommended to additionally fix the umbrella to the ceiling.
Second mounting method
The second way is mounting wall or island exhaust hoods through studs and collets to the ceiling. In the upper horizontal plane, along the edges of the exhaust hood, four holes are drilled or special ears are welded for the studs, which include four studs Ф8 - Ф10 mm, previously fixed in the ceiling. The method is quite simple and effective. The only disadvantage of this method is that the height of the ceilings should not exceed 4350 mm, since the increased height will not allow the use of standard studs up to 2 meters long.
Installation of exhaust hoods on cables or chains
The third way is installation of exhaust hoods on cables or chains, through brackets and anchors to the ceiling. In the upper horizontal plane of the umbrella, four special mounting brackets are welded into which a cable or chain is fixed through a carabiner, the other end of the chain is fixed to the ceiling. In this case, the height of the ceilings is not very important. The main possible problem with the installation of exhaust hoods in this way is associated with the unsteadiness of the structure. It is quite difficult to tie a rigidly unfixed structure with air ducts.
Mounting the hood with special support frames
The fourth way is installation of exhaust hoods using special support frames. Depending on the overall dimensions of the lower section of the exhaust hood, a support frame is made, on which the exhaust hood is installed from above. It can be rectangular or square on four legs, the height of which is selected individually for each object. Legs through special support plates are rigidly attached to the floor. Support frames are made of stainless steel profile 30x30 or 20x40 mm. Thanks to proven technology, the use of modern metal-working and metal-cutting tools, EuroVentGroup specialists achieve perfect geometry and a very presentable appearance of the exhaust hoods produced by the company and the supporting structures necessary for the installation of these exhaust hoods. In such cases, where the technological equipment is located far from the walls, the ceiling height is quite high, and the customer makes high aesthetic demands on the arrangement of local exhaust ventilation, the use of exhaust hoods complete with support frames from EuroVentGroup remains the only right solution.
Exhaust hoods are installed in many places, premises and institutions, primarily associated with certain household or culinary and food activities: in kitchens and kitchen workshops, in restaurants, cafes, canteens, in the country, in the garden, etc.
An exhaust hood is an important engineering structure that can be very useful even in domestic conditions, at home or in the country, and is not at all replaceable at catering establishments. Let's consider in more detail what it is and why it is needed.
main destination
A ventilation umbrella or dome is a device whose main task is to ventilate the air space of various rooms and territories. Located above sources of high temperature, humidity and various odors, for example, over stoves and cooking surfaces, exhaust domes remove hot air with various unfavorable impurities from the working area, thus refreshing the atmosphere of the room.
The range of tasks of this ventilation device includes air purification from many substances that cause harm and discomfort, among them: steam, soot and soot, grease, dust, various odors and chemical reagents (acids, salts, alkalis).
Therefore, the scope of exhaust hoods is very wide. These structures are installed not only in kitchens, but also in chemical and food industries, laboratories and other similar establishments where there is an increased risk of air pollution.
Exhaust dome device
The base of the exhaust hood is a metal dome with a hole connected by an air duct to the ventilation system. Full functioning is ensured by special devices, such as:
- Grease filter. Serves for cleaning of air masses from particles of fats and oils.
- Sparkling mesh. It is necessary when working with sources of open fire.
- Lamps. Additional lighting with lamps built into the dome body.
- Pendants. Mounting elements that hold and distribute the weight of the unit.
- Turbines. They provide capture and promotion of the air flow through the filters to the air duct.
Exhaust hoods should be made of materials that have good corrosion resistance and comply with modern sanitary standards. Such material is "food grade stainless steel" - a special grade of stainless steel produced specifically for food industry equipment and characterized by increased resistance to aggressive chemical environments.
Many stainless steel ventilation domes are constructed using inverter argon arc welding to increase durability. Thanks to this method, the quality of welds, wear resistance of equipment and the life of the unit as a whole increase.
The exhaust hood device includes an air filter, which can have various functional additions: spark arresting nets, grease traps, labyrinth filters, etc. The installed filters are also subject to sanitary and hygienic standards and requirements. In addition, they, as a rule, have a very attractive appearance, and the design allows them to be removed for cleaning or replacement.
Varieties of umbrellas
All modern ventilation units are developed not only taking into account functional, technical and sanitary requirements, but also for design and aesthetic reasons. Of course, it is not easy to turn such a serious unit as an exhaust dome into a decor element, but this does not prevent it from fitting perfectly into almost any interior, especially in an industrial environment.
The appearance of the hood has some space for decoration. For example, the outer steel coating can be polished or mirrored, but it can also be matte. Strict forms, straight lines and shiny mirror surfaces not only look good in production shops, but also perfectly complement high-tech or minimalist interiors.
Exhaust hoods can be divided into two types: household (kitchen) and industrial (industrial). There is no fundamental difference between them, but there are some technical differences. For household modifications, for example, a kitchen umbrella, in comparison with industrial ones, the following features are characteristic:
- Smaller dimensions. Such units are designed for standard sizes of conventional stoves. The air turbine is much less powerful or absent altogether.
- More simple and compact grease filters (paper) are used.
These differences are not always clear-cut. For example, an island-type ventilation dome installed in a spacious kitchen in a private house may not differ at all from an industrial one. At the same time, air umbrellas for outdoor barbecues and barbecues, on the contrary, are extremely simplified devices, down to the primitive, representing a metal arch without any additional devices.
However, ventilation equipment located indoors must necessarily have a complete set of functional elements: a turbine, a grease trap, a spark arrester, etc. This also applies to such units as exhaust tables and cabinets, which are more related to the chemical industry than to the food industry. They are mainly installed in laboratories.
Design and installation features
According to the type of construction, exhaust hoods are wall-mounted and island. Wall models are mounted directly on the wall, directly above the work surface. Island ones have a more complex design, as they are attached to the ceiling and hang over the equipment located near the center of the room, away from the walls. The wall dome has one row of filters, and the island dome has two.
If the wall umbrella has a significant mass and dimensions, additional hangers, brackets and chains are used for auxiliary fixation of the device. To give the structure rigidity and stability, its shape is given a trapezoidal profile. This allows you to increase the maximum allowable area of the dome for hanging over large equipment.
Island-type ventilation units circulate air flows in a much larger volume than wall-mounted ones. Therefore, they are excellent not only for forced ventilation of air in the center, above objects remote from the walls, but also for ventilation of the entire volume of the room as a whole.
The quality and stability of the ventilation dome depends not only on the choice of its type and modification, but also on the correct installation of the unit above the working area. The fume hood must be hung exactly above the location of active kitchen, industrial or laboratory appliances that pollute the air: stoves, deep fryers, braziers, burners, chemical containers, etc. It is necessary to ensure the coincidence of the centers of the umbrella and the active surface.
It is important that the dimensions of the exhaust unit slightly exceed the dimensions of the equipment below it.
For conventional kitchen appliances, a couple of centimeters of difference is sufficient, and for larger installations, standards require an increase in the size of the dome by 10 cm or more. The height of the suspension of the structure above the working surface should be from 70 to 110 cm.
Conclusion on the topic
Thus, we found out what it is, an exhaust hood, what its device and purpose are, and also figured out the types and modifications of dome structures and the intricacies of their installation. This data will help in the selection and purchase of equipment, its operation, maintenance and repair.
