In residential buildings, mass housing has traditionally performed the natural ventilation. However, the sustainability of its work depends on many factors, whose impact is often negative impact on indoor air quality. It should be noted that it is not always maintained the requirement for vents in a narrow wing, or swing-out mechanism in a narrow leaf, or, if necessary, noise valve. Low quality termination of building intercommunication holes and seams and leaks doors in flats reduces the efficiency of ventilation by 15-30%. Looseness in blocks of ventilation ducts, obstruction of doing the hood, in some cases even unworkable. If the ventilation is designed poorly, or is clogged, or illegally reconstructed, the situation with the required ventilation is almost hopeless. Mold damage on the walls, high humidity indoors is called, besides increased tightness of windows, by the fact that in the new building organizations build and rent houses in a short time, and tenants occupy apartments, which a year or two "wet" wall . To create a normal climate in these apartments must be airflow, and sometimes even drying of the walls. Design decisions ventilation through open air vents, transoms, rotational flaps, or significantly reduce the thermal efficiency of window designs and a comfortable stay. The use of synthetic finishing materials in residential buildings, the proliferation of dust mites in the apartments also lead to a reduction of indoor air quality and improve ventilation requirements. Increased dust in the outer atmosphere makes it necessary to clean incoming air. The disadvantages of natural ventilation should be assigned and that it is difficult to reconcile with the modern requirements of energy conservation. When installing thermostats on heating devices, there is a real opportunity to save heat in the heating system. In this case, from 30 to 75% of the installed thermal power system is the need for heat for heating ventilation air. Energy conservation would be more effective if ventilation could operate with variable airflow. Organize such a regulation when natural ventilation is almost impossible. Ventilation system with a mechanical drive. Equipment for residential air-supply systems, ventilation is much less than the mechanical exhaust as it substantially increases the cost of the project due to the cost of the system itself, a place to supply plant and the space required for installation of air ducts. The advantage of mechanical air handling systems is the guaranteed supply of design flow supply air into each apartment, the ability to provide fresh air and reduce the allergic diseases, the possibility of air distribution, excluding the blast, regardless of weather conditions on the street, the possibility of energy savings by utilizing the heat of the exhaust air to heat supply. The disadvantages, apart from cost, include deterioration of the ionic composition of indoor air, electricity costs on the movement of fresh air, possible additional heat losses in the ventilation chamber and ducts. Usually set at least two air supply systems in the building. If possible, the air intake of the green zone, plenum chamber is located in the basement. If the bottom of the clean air pick up is not possible, then it is installed on the upper technical floor. Inlet metal ducts - stems from the "companions" - located in the technical mines inside the apartment, from which the distribution of supply air directly to rooms. In this case, wiring the supply air is carried out at boarding ceiling intra hall. In tall buildings in each zone to a height of 10-12 storeys designed independent trunks inlet ducts. In winter, incoming air is fed heated to a temperature of 20 ° C in summer - outside. In addition, the plenum chamber air is filtered in a dry-type filters, EU 5, EU 6. Fan inlet system selected on the basis of disposable pressure required to join intra ventilation network. Application of mechanical air-supply system requires, as a rule, use and mechanical ventilation with roof fans. The presence of a mechanical supply and exhaust system makes it possible to recover heat from exhaust air. The use of ventilation systems with plate recuperative heat exchanger in central Russia in the most cold peaks requires pre-heating fresh air to avoid freezing of condensate in the path of exhaust air. Known scheme with door-to-door supply and exhaust systems and heat recovery, where the preheating of the flow is carried out individually, in small power electric. There is a positive experience with such systems in low-rise buildings. Exhaust ventilation system with a mechanical drive. During mechanical ventilation, and especially with the air-supply valve, restricting the passage of air, you should pay attention to the density of residential doors. Most breathability doors creates a problem flowing exhaust air of the apartments on lower floors of the stairwell in the apartment the upper floors, with the result that, even with a well-functioning ventilation, fresh air is greatly reduced. In buildings with one-sided arrangement of apartments, this problem is compounded by the possibility of horizontal spillover of the flats on the windward side of an apartment leeward facade. Snip "Building Heat Engineering" presents to the front door apartment demand high integrity, providing breathability no more than 1,5 kg / (h • m 2), which practically has cut flat on the staircase, the elevator shaft. In real terms, this requirement is usually not performed. Where natural ventilation rate of the density of the doors could be even lower. When mechanical ventilation in the apartments are great dilution, and leak through leaky doors are not excluded. Decentralized systems door-to-door ventilation. Trying to avoid the shortcomings of centralized supply and exhaust ventilation system led to the development of a decentralized door-to-door supply and exhaust system with heat recovery. This system has the following advantages: a constant ventilation of living space, the relative humidity in the room does not exceed 45%, thanks to the double filtration ensured a supply of clean air, saving heat by utilizing up to 20%. The so-called system of «System Airaterm» allows you to smoothly adjust the air, taking into account the solar radiation and wind speed, reaching a thermal efficiency of 66-80%, and providing a humidity in the room at the level of 45-55%. On admission of air at a rate of 34 m3 / h, the noise level is 21 dBA (almost inaudible). At flow rate of 60 m3 / h Noise level - 32 dBA (quiet rustle of leaves), and at the rate of 80 m3 / hr - 39 dBA (the fan noise a computer). Such a system with recycling already operating successfully in Germany in five-and ten-story building. Ventilation system with heat recovery (Erfurt). The basic principle is that for the first time for each apartment unit is installed ventilation and air removal with built-in heat exchanger. This means that every apartment gets its "Air". Along with the installation of ventilation equipment should provide a quick supply of the supply and removal of exhaust air. This purpose is served by separate vertical shafts that pass through all residential floors. Large-sized parts of the system (device ventilation shafts supplying fresh air and exhaust air outlet) are located in a sanitary pit, between the kitchen and bathroom. In addition to high-performance heat exchanger, air handling unit is equipped with a so-called fan-box through which the heat exchanger is sucked in the exhaust air and supply air is passed under pressure principle backflow. If you close the passage back to the airflow direction, distributed in small channels, the supply air takes away from the exhaust air up to 93% of the heat (efficiency). Part of the venting device is internal filters that, in order to protect the heat exchanger, filtered kakpritochny and exhaust air. The exhaust air of residential premises through the valves is sucked into the kitchen and bathroom, which, in turn, are equipped with additional filters. After passing through the heat exchanger, exhaust air is sent to the central shaft, which leads him through the roof outside. Since the supply air before passing through the ventilation device also passes through an external filter in the central mine supply air, it is obvious that this air flow is subjected to double filtration. "Preheated" fresh air on the flat (pallet) channels are distributed mainly in the hall, and the so-called long-ejection nozzles, blown into each room of the apartment. In the hall needed for the air distribution channels should be flat "cached" false ceiling. Depending on the location of the heat exchanger in the mine, requires an observation door in the bathroom or in the lobby. Due to the need of accommodation in sanitary pit, this setting is particularly suitable for use in new buildings and a complete renovation / modernization of sanitation pipes. First and foremost, are the following positive aspects of the system used, improving the quality of housing: the constant corresponding to the standards of ventilation of living space and disposal of his air to avoid / prevent the harmful effects of condensation in the areas of thermal bridging, since the relative humidity is below 45% and the maximum noise protection of buildings through the windows sealed construction, thanks to the double filtration ensured a supply of fresh air (there protivopyltsevye filters «Pollenfilter»). Comparison with other technologies. Comparison with other technologies, which include measures to decrease emissions CO2, shows that the "heat recovery" in relation to thermal solar installations, photovoltaic (photovoltaic) installations can be seen as a much more economical. The relation between energy saved and investment costs for ventilation and removal of air from a decentralized (relating to the apartment), heat recovery is 6-10 times more favorable indicators of the aforementioned technologies. Waste disposal issue, using existing photovoltaic installations (heavy metals such as cadmium, lead, etc.) do not arise after the expiration of the service units with heat recovery. When outdoor temperatures from -10,5 ° C only due to the effect of regeneration the air warmed waste heat to a temperature of 17,1 ° C. The temperature of the exhaust air was 19,0 ° C. Analysis accumulated over recent data indicates a cost overrun of about 25% of heat at the facility without installation of heat recovery. Need to improve standards for the design of ventilation systems. Comparison of our standards of air exchange with the rules of Germany shows that for small apartments our standards more stringent, since the lower limit air they do not fall below 110-140 m3 / h. At the same time, according to German standards in the flats up to 50 m2 of total area required air flow rate, equal to 60 m3 / h, and the apartments 50-80 m2 - 90 m3 / h. Some experts suggest to consider the base flow rate, and rate of extraction - the peak. Then the Russian and German rules would be closer. However, this proposal is only possible with controlled ventilation, which, as noted above, it is easier to implement when a mechanical system. The materials of the International Seminar organized by the Moscow Government, the Delegation of the TACIS program and OAO SanTechProm, offers ventilation design, capable of operating in two modes: base and peak, with a temporary increase in consumption over the base. Moreover, when the basic mode ventilation should be 0,4-0,5 multiplicity of flat or 20-30 m3 / h per person, and in peak mode, the consumer - not less than 0.8 multiplicity and more than 30 m3 / h per person. Such a system could provide adequate ventilation for all flats in compliance with air quality. Long-standing observation in Western Europe have shown that the growth of mushroom fungus contribute not only to a very low ambient air temperature, but above all, the air temperature is between 8 and 18 ° C. The reason for their growth is the high moisture content while decreasing ventilation due to reduced thermal pressure difference. The foregoing is only slightly shows the need to adjust the rules in force today.
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