Forced ventilation. Functional features of air handling units

Fresh air ventilation ensures clean air even in closed rooms

Natural and forced ventilation of premises

Supply ventilation, unlike natural ventilation methods, has the function of cooling the air and saturating the room with oxygen. The need to install forced ventilation is explained by the massive use of sealed plastic windows in the premises. At the same time, indoor ventilation is reduced to nothing: the room becomes stuffy, there is a high degree of humidity and the formation of a fungus harmful to the body.

Air movement pattern in a house with natural ventilation

Forced ventilation systems can be of several types. These include the uncomplicated design of the window valve, which is mounted on the top of the frameplastic window and allows fresh air to enter. Another device is a supply fan. It is installed in a window opening or in a prepared wall opening. These elementary air handling units have several disadvantages:

• the air entering the dwelling is not cleaned, which is important when the windows face the outer (carriageway) part of the street;
• in winter, the air flow has a low temperature, which can negatively affect health;
• damp air entering the room may damage furniture (swelling or cracking), peeling wallpaper, etc.

Reinforced-plastic window with installed air damper

Varieties of supply ventilation systems

Supply ventilation systems can be divided into several subgroups.

With and without duct:

• channelless - the air flow enters through special wall openings or windows;
• ducted - air is supplied through the duct.

Ventilation system design:

• prefabricated - a network of individual devices that will be connected by an air duct;
• monoblock - several elements are assembled into one supply ventilation device (fan, filter, heater, silencer, etc.)

Recuperator is a simple and effective solution for organizing decentralized energy-saving ventilation of individual rooms

By using the ventilation method:

• local (local) - fresh air enters a specific place in the room;
• complex - in which there is a measured exchange of air throughout the room;
• emergency - anti-smoke security systems;
• recuperative (with heat recovery) - recuperation occurs due to the heat of the outgoing flow. Heat recovery device (recuperator) is expensive equipment, but its payback period is rather short.

Useful advice! Simple supply ventilation systems can be assembled and assembled by hand.

Self-regulating diffuser for natural ventilation

Forced ventilation. The device, functioning and types of systems

Supply ventilation is able to provide sufficient ventilation for an apartment, private house or office space.

Related article:

Supply ventilation in the apartment with filtration. Indicators of stagnant air. Types and principles of supply ventilation in the apartment. Do-it-yourself installation and installation of equipment. Helpful hints.

All elements of the supply unit are assembled in a noise-insulating block, which is compact in size and can be installed by hand on loggias (balcony) or directly indoors.

Air flow diagram in a house with forced ventilation

Forced ventilation. Device

The supply ventilation device consists of the following elements:

• air intake grill - through it, air enters the ventilation system, prevents precipitation and small objects from entering;
• air valve - an automated valve that blocks the entry of air from the outside when the ventilation mode is off;
• filter - serves as a protection for the ventilation system. There are several types of filters for supply ventilation - filters of coarse, fine and purely fine cleaning.
• air heater - heats the incoming air in cold weather. For small rooms, electric heaters are used. With an area of ​​more than one hundred squares, it is recommended to use water heaters;
• muffler - serves to absorb noise during fan operation;

Supply ventilation device

• fan - provides air supply from the street and sufficient pressure of air flows in the system;
• air duct - distributes air in the room. The design and size of the duct is set depending on the calculation of the air exchange rate;
• air distributors - devices for supplying air from an air duct directly into a room;
• control system - a device for regulation, control and monitoring of ventilation. Includes automatics to control the air heater, air valve, filter clogging control.

The breather will provide fresh air in the apartment even with closed windows

Supply ventilation with heated air

One of the types of supply unit is supply ventilation with a heat recovery system. It allows the incoming air flow to be heated by the heat of the air removed from the room, which significantly saves energy. A large part of the outside air flow is heated by a heater. The supply ventilation system with heat recovery is equipped with a heat exchanger connected to the supply and exhaust ventilation ducts.

The air displaced from the room, moving through the recuperation device, transfers heat to the incoming air flow. In this process, the air flows (incoming and outgoing) do not mix. By means of supply ventilation with recuperation, it is possible to effectively reduce the cost of heating the incoming stream during the cold season. And in the warm season, when the room functions air conditioning with a supply ventilation system, with the help of recuperation the incoming warm stream is cooled to the required temperature.

Scheme of work of a recuperator with air heating

Supply ventilation with heated air can be equipped with an electric or water heater. For supply ventilation of houses, large offices, warehouses, water heaters are often used, since the issue of energy saving is especially acute.

Supply ventilation with heated air has automatic control, which is carried out by means of a remote control. Do-it-yourself installation of such a system is associated with accurate calculations, so it is better to entrust it to professionals.

Example of arrangement of ceiling ventilation

Supply ventilation control

The control is carried out using a separate control panel. Fresh air flow rate is regulated (five-step setting), air outlet temperature, timer is built in.

Automatic settings allow you to synchronize the on / off of the supply fan. There is a protection system that provides emergency shutdown. The fan motor winding is equipped with thermal protection (when the protection is triggered, the automatic device will turn off the fan). A heater with a built-in thermostat guarantees protection against overheating or fire.

Air heating system - a universal solution for combining space heating with ventilation and air conditioning

The supply units are equipped with a pressure gauge that measures the difference in air pressure at the filter and in the area where the supply ventilation valve is installed. So, when the system is forced to stop, the flow of outside air into the room is automatically stopped. In addition, the pressure difference can increase depending on how dirty the filter is. As soon as the contamination limit of the filter exceeds the permissible level, the system will notify you of the need to replace (or clean) it. This can be done by hand. In budget supply air inlets, it is simply proposed to fix the filter life count.

The valve for fresh air intake attracts with its small overall dimensions, low price, ease of installation

Supply ventilation valve

One of the types of ductless ventilation system is a supply ventilation valve. Its function is that it lets the outside air into the house without opening the vents and windows, excluding dust and noise from the street. The device helps to normalize the humidity in the room.

Do-it-yourself installation of the supply valve is quite simple. The valve is installed in a pre-drilled hole in the wall above the heating radiator. The cold air is heated by battery, thanks to which the room is always warm. The wall damper is equipped with a sound absorber and a coarse air filter. The valve is controlled by a damper that regulates the volume of supplied air.

Installation diagram of the supply valve built into the frame metal-plastic window

Air heating by forced ventilation

One of the modern and most importantly promising types of heating is air heating. The possibility of such heating is provided by combining space heating with ventilation and air conditioning. During the cold season of the year, warm air is supplied through the same duct system that carries cold air in hot weather. This is the versatility and economy of air heating, which can be used in a residential building or office.

Air heating functions due to supply ventilation with an air heater, which is heated by a water-based centralized heating system.

Supply and exhaust ventilation system design

Air heating is equipped with an automation system that automatically regulates the supply of the required amount of heat.It is possible to set the heating system to an economical mode (for example, when there is no one in the house, you can reduce the temperature to a minimum). In the event of a return to normal heating mode, the rooms in the house quickly heat up.

Useful advice! The calculation and design of the heating of the supply ventilation is carried out on the basis of taking into account all design features and technical parameters of the parts that make up the ventilation system. Accurate calculation and correct installation guarantee trouble-free operation of the air handling unit.

Air heating is equipped with an automation system that itself regulates the supply of the required amount of heat

When assembling and installing heating supply ventilation in the house with your own hands, it should be remembered that the calculation of the values ​​of supply ventilation is rather complicated and specific. It will not be superfluous to consult with experts in this field.

Supply ventilation calculation

The calculation of supply ventilation for a house is made taking into account the purpose of the premises, since different rooms in the house have their own microclimate. It will be logical if the calculation of ventilation is done by professionals. When starting to calculate ventilation with your own hands, it is necessary first of all to take into account the power of the system, the configuration for each room, heat recovery, and automation control.

The calculation of supply ventilation for the house is made by a specialist

When calculating ventilation, consider the following:

• general purpose of premises (country house, apartment, area of ​​premises, number of people, air humidity);
• draw up a diagram for calculating the cross-sections of the duct;
• air exchange (the calculation can be made using the table drawn up according to the standards);

Useful advice! It should be understood that even an insignificant error in the calculation can lead to a decrease in the efficiency of the ventilation system and an unreasonable increase in energy consumption.

Modern ventilation systems fit perfectly into the interior of the house

• develop a plan that includes all schemes and calculations;
• coordinate the project with the competent authorities;
• do-it-yourself installation of supply ventilation for the house.

Ventilation systems are an important element in the design of industrial buildings, offices and residential buildings, since their high-quality functioning is directly related to the health of the people in them.