The microclimate in modern living quarters often leaves much to be desired. Since most apartments and country houses have plastic sealed windows, the air in the room stagnates and is saturated with carbon dioxide. In order to prevent this from happening, it is worth installing a ventilation system in your home. There are several varieties of such designs. However, the most effective is the supply and exhaust ventilation. We will talk about the advantages and disadvantages, as well as the design features of such systems, further.
Types of ventilation
All such designs are divided into three main varieties:
- Exhaust. This is the simplest type of system, well known to all owners of urban apartments. Air supply devices are not provided for in such structures. It comes from the cracks in the windows and doors, and is naturally discharged along the riser. Sometimes in the kitchen an additional domestic exhaust system is installed. The price of equipment of this type is the smallest (3-5 thousand rubles).
- Supply This type of ventilation works in the opposite way. That is, special equipment is installed in the room, forcing fresh air from the street. Such systems can be either monoblock or channel.
- Supply and exhaust. This is the most complex and most efficient type of ventilation system. Typically, private homes use modern air handling units with heat recovery.
Next, we consider how the last kind of systems actually functions.
Design features
When using this method of ventilation, two units are mounted in the room, one of which supplies air, and the second takes it off. In addition to this equipment, the room is going to a system of underwater and diverting canals, providing improved microclimate in all rooms of an apartment or house. The convenience of supply and exhaust ventilation lies in the fact that absolutely any additional equipment can be built into its design . This can be, for example, air humidifiers, atmospheric pressure regulators, air conditioners, etc. Almost always, the supply and exhaust system is supplemented by a recuperator. This is a very useful device, and therefore we will further examine what it is in more detail.
Recuperator
This equipment is designed to collect heat from the polluted warm air removed from the rooms and return it to the cold air coming from the street. The recuperator consists of:
- Several plates made of paper or aluminum. Heat transfer occurs when air passes between them.
- Low-power heater. This device heats the incoming air additionally.
- Bypass. This unit provides uninterrupted operation of the recuperator. The room air, passing between the plates, cools down, as a result of which condensate collects on the latter. In cold weather, this water freezes. As a result, the recuperator itself freezes up and ceases to function. The bypass is designed to allow the supply air to bypass the plates from time to time. In this case, it enters the premises, almost without heating. Room warm air, passing through the plates of the recuperator, quickly defrosts them. At the same time, water flows into a special receiver.
Not so long ago, specialists from companies that produce ventilation systems found a way to prevent freezing of the heat exchanger without the use of a bypass, and therefore heat loss. In such aggregates, plates are made of hygroscopic cellulose. Moisture from the exhaust air does not settle on them, but is absorbed. Then it passes through microscopic pores, seeps onto the other side of the plates. As a result, the air entering the room from the street is humidified. Thus, such a design avoids heat loss and at the same time prevents air drying in the rooms of an apartment or house. Forced-air and exhaust installations with heat recovery are currently the most popular.
Principle of operation
Similar systems operate as follows:
- A powerful ventilation system draws in air from the street and delivers it through a short duct to the recuperator. Here it is warmed up and enters the canals, spreading it throughout all the rooms of the house.
- Additionally, exhaust ventilation is installed. The exhaust air is removed, previously also passing through the recuperator. The latter can be installed in the attic or in the basement.
In the event that it is too cold outside, the air heater is included in the system. Without it, the air inside the heat exchanger in the winter is heated to about 14 grams. With an efficient heating system, this is usually enough. When the heater is on, heating can occur up to about 22 grams. On very frosty days, this may not be amiss. Thus, the supply and exhaust systems with heat recovery, among other things, provide additional comfort in the house in the winter.
Air ducts
The supply and exhaust system lines are mounted inside the ceilings and behind the wall cladding. Most often, modern systems use flexible corrugated round insulated air ducts. Two branches are usually brought to each room - supply and exhaust. The first goes near the floor, the second is located on the ceiling.
Design Features
When developing a mounting scheme for equipment such as supply and exhaust units with heat recovery, the SNiP and GOST standards must be taken into account. Their observance ensures the most efficient operation of the system and the safety of its operation.
Since the design of the supply and exhaust ventilation is a technologically very complicated procedure, it is usually assigned to specialists. It is very difficult to draw up a scheme yourself. Only properly assembled ventilation systems operate reliably. GOST 12.4.021-75, for example, allows for operation only past commissioning activities and having all the necessary design passports. For a private house, perhaps this norm does not play a decisive role, but with improper installation, the owners of the house will definitely have some problems (up to the smell of the toilet, for example, in the bedroom or in the kitchen).
Installation
Actually, the assembly of the system itself is nothing complicated. Often, homeowners, on a commissioned project, mount such a structure as a supply and exhaust system, and air ducts on their own. The latter are attached to the structural elements through special clamps. Branches suitable for the rooms are connected to the main highway through fittings and tees. The recuperator is installed on a flat horizontal surface in a separate room. Fastening of the inlet and outlet ducts to it is carried out in accordance with the instructions provided by the manufacturer.