Ventilation units

In ventilation systems with mechanical induction, nowadays, the inflow and supply and exhaust ventilation installations are increasingly being used. Ventilation units are fans mounted in one or more blocks and a set of components suitable for a particular situation, such as a louver valve, filters, mufflers, drip traps, humidifiers, coolers, heaters, recuperators of various types. Moreover, the number of these components in one installation, depending on the situation may be different.

Types of ventilation units.

By way of installation, ventilation units are: hanging (more often forced-air hanging ventilation units), stationary ventilation units for conventional floor mounting and roof ventilation units, which differ from the previous ones, mainly in the direction of delivery and collection of air, and the external execution of the housing. By appointment, ventilation units are exhaust, inflow ventilation units and supply and exhaust ventilation units. According to the structural features of the ventstates can be monoblock, and can be assembled from separate units. Ventilation units are good in that in most cases do not require a special separate room, can be installed on the street, including on the roof, occupy much less space, can be used in systems with any productivity and aerodynamic resistance in the network, are as accurately as possible debugged on a specific system and allow fully automated the "climate process" premises or its separate zones.

Hanging ventilation units can have a maximum performance of up to 6000 m³/h, stationary ventilation units have a wider range of performance - from 1,000 to 100,000 m³/h or more. Specially designed fans allow you to create quite large headlights in modern ventagregats, and the multi-layered housing design minimizes heat loss and noise.

Supply and exhaust ventilation units can be supplied with filters of various degree of purification, water and (or) electric heaters, gas burners, water or freon coolers of different power, humidifiers of different types, drip traps. That is, almost any configuration of the parameters of air supplied to the room by ventilation unit.

In addition, in conditions of constant rise in energy prices, currently ventilation units are often equipped with recuperators of various types and designs, which allow the transfer of part of the heat of exhaust air to supply air.

Recuperators of supply and exhaust units

Cross-flow recuperators, due to their design, direct the supply and exhaust air flows to the interconnecting channels without mixing and through the surface of thin plate cells the heat from the exhaust air is transmitted to the inlet. The efficiency of such recuperators can reach 75%.

Rotary recuperators have a design through which the heat of exhaust air is transmitted to the intake air by means of a slowly rotating disk, which in turn is a set of plenty of plate perforated discs. Rotary recuperators allow a small (up to 15%) mixing of exhaust air to the inlet. It somewhat narrowes the scope of their application, but the efficiency of rotary recuperators is much larger than the cross-current - up to 85%, depending on the amount and parameters of exhaust and tidal air.

When the dimensions of the ventilation chamber or other features of the ventilated spaces do not allow the placement of an inflow and exhaust unit in one place, then a glycol recuperator may be used.
Glycol recuperator works as follows: through two separate heat exchangers, the heat carrier - glycol circulates in the exhaust and supply streams; the exhaust air sends heat through a glycol heat exchanger, which, in turn, heats the plates of the tidal heat exchanger. The distance between the exhaust and tidal units can be considerable and is limited only by the technical possibilities of laying pipelines between the heat exchangers, but the efficiency of the glycol recuperator is small, much lower than the cross-current and, moreover, the rotary recuperator.

Today, many manufacturers have a range of standard ventilation units for relatively small performance. This is a ventilation units for cottages, offices, small commercial premises, equipped with water or electric heaters, or without them, recuperators of various types. For high performance or any special conditions, ventilation units are selected and manufactured individually, under the order. After calculating the ventilation system, with all the necessary parameters for selection and design features, the designer issues a technical specification for the representative of the manufacturer and after some time receives a set of printouts with the necessary parameters, technical characteristics, dimensions and design. Some manufacturers place software selection software on their sites on the Internet, which allows online to create ventilation units of any configuration of the designer himself.