Correctly made local ventilation is the key that the air in the house will be clean and fresh. It helps to cleanse the atmosphere of the room of excess carbon dioxide and dust particles and helps to create a comfortable microclimate in the room.
In what cases are local ventilation needed
Types of ventilation systems for home and their features
Installation of local ventilation is necessary in those rooms where there is a source of heat or moisture. Moreover, this is not only about the sauna. Such ventilation systems are necessary in kitchens, where a certain part of the oxygen is “eaten” with carbon dioxide formed during the operation of the slab. They will not be superfluous in bathrooms, increased humidity in which contributes to the development of mold and fungi.
In private houses, the local ventilation system is built at the construction stage. Vertical boxes are laid in the walls of the bathroom and the kitchen, along which the air will leave the room. There are such hoods in each apartment building – as a rule, their holes are closed with metal or plastic gratings. This ventilation works not only in those rooms where there is a way out, but in all the others thanks to the air circulation in the house or apartment.
How is the calculation of local ventilation done?
Submitted ventilation systems from separate blocks
In order for local ventilation to work in full power, you must correctly calculate it. Its power is calculated based on the change of three indicators:
The multiplicity of air exchange is a number showing how many times the air in the room should change within one hour. According to the sanitary standards adopted in the Russian Federation, this indicator is 12 units for the kitchen.
The volume of the room.
The coefficient of the extract of the extractive strength compensating for the resistance of the bends of the duct. The value of the indicator is 1.3 units.
So, suppose that the area of the existing kitchen is 8 m2, and the height is 2.5 m. Accordingly, the volume of the room will be 20 m3 (8×2.5). Since the multiplicity indicator is 12 units, we multiply 20 m3 by 12 and get 240 m3 per hour. We multiply the resulting number by 1.3 and get the final result, which will be 312 units. Consequently, ventilation must be calculated so that its power is enough to perform air exchange in the amount of 312 m3 in one hour of work.
Installation of local ventilation
First, consider the device of local exhaust ventilation in the bathroom. Its simplest system, consisting of boxes and outer grate laid in the wall covering their output, is installed in each house. But most often it happens that its power is not enough to maintain normal air circulation. In such cases, instead of a conventional lattice, a special hood-fan is installed, operating from the mains. You can connect such a fan directly to the lamp, and then it will start his work at the same moment when you turn on the light in the room.
All work on the installation of electrical equipment must be performed by qualified electricians.
Now let’s talk about the arrangement of hoods in the kitchen. It is installed directly above the kitchen slab. Before buying, you need to conduct calculations that we talked above and purchase a device with appropriate power. The height height of the hood is determined by the type of plate. If you have a gas stove, then the distance between it and the air cleaner should be at least 75 cm. It is not recommended to reduce this distance, since a powerful hood is highly likely to blow out the flame. If you have an electric stove, then the gap can be reduced to 60 cm. The width of the hood is determined in accordance with the size of the kitchen slab – it should exceed it by about 10 cm. This will allow the device to do well the work assigned to it and collect all combustion products without a trace.
During installation, the kitchen hood is connected to the ventilation box using special channels. Very often used a corrugated pipe made of thin aluminum, but professionals recommend using a box with a smooth inner surface for this. Such a system will provide the best departure of “worked out” air, and, therefore, the hood will work with a greater power. It is worth noting that the inclusion of hoods entails a decrease in the pressure in the room. It is very simple to return this indicator – for this you just need to open the door or window.