The ventilation system should be in any room, regardless of its purpose. Otherwise, the room will not only be suffocating air, but also fungi and bacteria will develop.
Purpose of ventilation
Many people very often do not understand the purpose of the ventilation system. They believe that you can simply open a window to ventilate the room. But in winter, this procedure will be impractical. That is why the ventilation system is being installed. If it is absent, condensation will collect in the area of windows and doors. After a certain time, a fungus may appear in this place, which has a negative effect on human health.
In the absence of fresh air, rooms become dusty. In the absence of ventilation in the kitchen, over time, yellow and brown stains from grease and soot will appear on the ceiling and walls. If the room is not ventilated in a timely manner, this will lead to the accumulation of pathogenic bacteria and fungi in it, which will negatively affect the health of people who constantly reside in it.
Features of the system
The purpose of the ventilation system is to remove exhaust air from the room in which it is installed. Most often, the supply and exhaust ventilation systems are installed simultaneously, which provides them with an excellent quality of performance of their functions.
To ensure a favorable microclimate in the room, it is necessary to correctly calculate the ventilation. For this purpose, all the necessary units are taken into account to ensure the full operation of the ventilation system. If the calculation is carried out incorrectly, there will be an inadequate performance of the ventilation functions. This will lead to the appearance of fungus. With incorrect calculations, destruction of building materials and decoration of the premises is very often observed. At the same time, people who often stay in it constantly complain about the appearance of various diseases caused by bacteria and fungi.
Ventilation parameters
When calculating the ventilation system, it is necessary to take into account not only its parameters. The functions that this equipment can perform depend on them. Ventilation can be:
- exhaust, which remove exhaust air from the room;
- supply and exhaust, which simultaneously remove waste air and supply fresh air to the rooms;
- supply air, which supply fresh air to the room.
Exhaust ventilation is used in manufacturing plants, offices, warehouses, etc. The disadvantages of this installation is that it is unable to provide normal indoor air on its own. That is why, when calculating an industrial system, it is necessary to take into account the parameters of a particular room.
In modern systems, the presence of a variety of additional devices can be observed, with the help of which the air is purified, cooled or heated. They also provide the highest quality removal of old air.
Calculation features
Before proceeding with the arrangement of the fan, it is necessary to calculate it. For this purpose, its main parameters are determined, and tasks are set.After determining the required characteristics, the equipment is installed. The calculation of ventilation should be made in such a way that during it a determination was made:
- working pressure;
- consumption;
- air duct cross-sectional area;
- heater power.
The calculation is made according to the formula: L inflow = L exhaust = S whole house * 3. If necessary, specialists calculate the electrical energy that is used to ensure the full operation of the equipment.
How to determine system performance?
The calculation of the supply and exhaust ventilation should be done in such a way as to correctly find out its performance. It is determined in cubic meters per hour. To calculate the air flow rate, it is recommended that you have certain information correctly. First of all, it is determined what the height and area of the room is. In order for ventilation to fully perform its functions in a particular room, it is necessary to find out what purpose it has. An important factor is the presence of people in the room, or rather, their number.
To take measurements of the room, you must use a tape measure. To record the data obtained, it is necessary to use paper and a pencil. In order to make the calculations as correct as possible, a calculator is used.
To perform the calculation, the frequency of air exchange per unit of time is determined. For this purpose, norms are used. Which, according to the type of premises, are established by the rules of SNIP. Administrative, industrial, residential buildings are characterized by different parameters. When calculating the ventilation system, all heating devices must be taken into account. If the premises are for domestic purposes, then the air exchange rate is equal to one, administrative rate is 2-3.
If it becomes necessary to calculate the performance, it is necessary to determine the amount of air exchange in the room in accordance with the number of people who stay in it. For this purpose, the largest amount is taken. This value should become decisive when selecting the capacity of the ventilation system. In order to calculate the air exchange rate, it is necessary to use a fairly simple formula. For this purpose, the area of the room is multiplied by its height and the multiplicity value.
If it is necessary to calculate the exchange of air in accordance with the number of people, then for this purpose the amount of air consumed by one person is multiplied by the number of people. In accordance with the norms, one person consumes no more than 20 cubic meters of air per hour.
Determination of the cross-section of the air outlet
When calculating the ventilation system, it is imperative to determine its working pressure. A fairly important role in this aspect is played by the section of the air outlet of the unit. The determination of the working pressure is carried out according to the parameters of the fan, the number of transitions and the shape of the ventilation pipes. If the ventilation will be installed in a private house or apartment, then the cross-sectional area of the pipe should be 5.4 square centimeters per square meter of the room. When installing the unit in private garages and in industrial enterprises, a cross section of 17.6 square centimeters should rely on one square meter.
When determining the parameters of the ventilation system, it is necessary to pay attention to what speed the air flow should have. Most often, the speed selection is carried out using parameters from 2.4 to 4.2 meters per second.
How to determine the capacity of an air heater?
The quality of ventilation directly depends on the power of the air heater. That is why it is imperative to take this parameter into account when calculating. This procedure is carried out with the simultaneous installation of the exhaust and supply unit.In this variant of ventilation of the room, an air heater is installed, which heats the incoming fresh air.
When calculating the capacity of the air heater, it is recommended to take into account the air consumption. It is also recommended to consider the recommended intake air temperature and the required outlet temperature. These parameters are determined by SNIP. According to the indications of this document, the air temperature at the outlet should be no more than 18 degrees. The temperature of the incoming air directly depends on the area in which the ventilation will be installed.
Reducing the speed of air circulation is due to the presence of capacity regulators in modern installations. In winter, this leads to a decrease in the consumption of electrical energy for heating the incoming air. In order to determine the heating temperature of the incoming air, it is necessary to use a fairly simple formula. For this purpose, the power of the installation is divided by the air flow rate. After that, multiply the result by 2.98.
How to calculate electrical energy?
To create the most economical installation, the amount of electrical energy that is necessary to ensure its full operation is calculated in advance. The calculation of electricity consumption is carried out according to the ventilation capacity. Also, for this purpose, the conditions of its work and other parameters are determined. When the air heater is operating only in the winter season, certain adjustments must be taken into account when calculating.
To calculate the amount of electricity consumption, you must use a special formula. Today there are a large number of sites that provide an opportunity to make a calculation online. For the calculation, you can use the formula:
M = (T1xLxCxDx16 + T2xLxCxNx8) xAD / 1000, where T1 and T2 are temperature differences, D and N are the cost of electricity; AD - the number of days in a month.
This will greatly simplify the calculation process. When applying the formula, it is necessary to use the data of preliminary calculations: temperature differences in the region, the duration of the installation. In order to determine as accurately as possible the amount of electrical energy for a particular room, you need to find out its cost.
Anyone can easily calculate ventilation. For this purpose, it is necessary to know in advance the parameters of the room and the tasks assigned to the ventilation. For the calculation, you can use special formulas or online services.
