Design features of typical sections of fan installations and filters and methods of their selection are considered. Additionally, in fan sections, we note the following. For each nominal performance by air, typical fan installations are delivered by the manufacturer to any of the three values of full pressure required to overcome the overall resistance in the connecting network. As an example, the indicators of typical fan installations for nominal performance from 1 thousand are indicators. up to 7 thousand. M/h. In this case, the design of the veins mixing chambers designed to create a volume when mixing air flows and ensure the maintenance of neighboring sections; Distribution chambers providing the distribution of air flow in the air conditioner directly (along the air conditioner axis) and up, as well as the maintenance of neighboring sections; A duct is brought to the receiving valve, according to which, with open valve blades, the outer air enters m, processing to the air conditioning. As a rule, the receiving channels have pneumatic Inn electric drives, which are included in the circuit of the automotive installation electric motor through the automatic control system. When starting the fan to the operation, the drive ensures the opening of the receiving valve wings, and when stopping, the closing of the valve wits. The intermediate section is designed to ensure access to the inner part of the receiving valve and a dual valve. Consistently installed heating sections and provide external air heating, which received for processing in the air conditioning in the cold season. In the upper part of the mixing chamber, a passage valve is installed, to which circulation air from the serviced room (the first recirculation) enters the air duct (the first recirculation). An external and circulation air enters the mixing chamber; Their mixture goes on further processing in the nozzle chamber. Part of the circulation air through the air duct can enter the passage valve and further into the mixing chamber, without processing in the nozzle chamber. This use of circulation air is called the second recirculation; Its use reduces the consumption of heat and cold for the processing of air conditioned air. A mixture of air after the nozzle of the air of the second recirculation is cleaned in an oil self -cleaning filter, the maintenance of which is carried out through a mixing chamber and an intermediate section. In the heating section, air heating is ensured before supplying it to the maintenance of the room (second heating), and the degree of heating of the air in the second heating is regulated by the position of the wings in the double valve. The transition section is attached to the flanges of the intermediate section, which ensures the connection of the air tract with the suction opening of the fan. To ensure horizontal assembly and installation of sections are typical stands. The injection hole of the fan installation is connected to the supply air duct, according to which air conditioned air is supplied to the maintenance room. The considered scheme of the central air conditioner with the first and second recirculation is the most complete in the functions performed in the process of round -theomed preparation of air conditioned air. Therefore, on the example of calculating the elements of this air conditioner, you can establish the main methodological techniques for choosing typical sections. Before the choice and calculation of air conditioning elements, the following sections of the design study for the air conditioning system must be performed. External galvanized, any diameters. Fast and efficiently.