1. Calculation of heat balance premises Drawing heat and moisture balance for the air-conditioned room is well-known methods adopted in the heating and ventilating equipment. This should take into account all factors affecting the change in the state of indoor air. To produce heat balance premises must identify all income and loss of heat in the room. In different rooms, there are two main categories of thermal loads: thermal stresses of the outside premises (outdoor) Thermal stresses resulting in buildings (domestic) 1.1. External heat load External heat load represented by the following components: Teplopostupleniya or heat loss as a result of the temperature difference between outside and inside the building through walls, ceilings, floors, windows and doors. The temperature difference between outside and inside the building during the summer is positive, resulting in heat flow occurs from outside to inside the premises, and vice versa - in the winter, this difference is negative and the direction of heat flow changes Teplopostupleniya from solar radiation through the glazed area, this burden is manifested in the form of perceived heat . Solar radiation is always creates a positive heat load, in both summer and winter. In summer, this load should be compensated, but in winter it is insignificant and can be integrated with the heat generated by the installation of an artificial climate. Outdoor ventilation air and the entering air (due to infiltration) may also have different properties, which, however, almost always contrasted with the meteorological requirements of the premises. Summer hot and humid (in some latitudes of the opposite - dry) outdoor air significantly affects the functioning of the plant, cooling and drying air, winter is cold and dry (or vice versa - wet) ambient air must be heated and humidified. And only in the interim period between the two seasons outside air can, to some extent be used in the form of free cooling. It should be noted that the external thermal loads may have different properties, ie, can be positive or negative depending on the season and time of day. 1.2. Internal heat loads internal thermal loads in residential, commercial, or belonging to the service sector areas are composed primarily of: heat generated by people heat from lamps and lighting fixtures, household appliances: refrigerators, stoves, etc. (In dwellings) heat from working devices and equipment: computers, printers, photocopiers and so forth (in offices and other premises) in manufacturing and engineering facilities for various purposes with additional sources of heat can be: Heat production equipment Hot materials, including fluid and different kinds of semi-finished products of combustion and chemical reactions All the internal thermal stresses are always positive, and therefore in the summer they should be removed, and in the winter at their expense reduces the load on the heating installation. 2. Principles for the selection of air conditioning systems and ventilation problem of the choice of air conditioning or ventilation systems should be solved on the basis of the feasibility of comparative analysis of several options (2, 3 or more). You must fully consider and evaluate the facility for its requirements, chief among which are: 2.1. Sanitary requirements necessary to maintain a certain temperature or temperature and humidity. It should be noted that the maintenance of humidity greatly increases the cost of the project. Serve at room fresh air (natural or mechanical means) or use a recirculating system to remove air through the local or general exchange pumps extract (in the production building) or by using natural extracts (in a residential area) 2.2. Architectural Requirements Ability to install the outdoor unit on the facade of the building and the indoor unit - indoor (cabinet-type air conditioners) or boarding ceiling (split system with an influx of fresh air). Ability to install central air conditioner on a technical ground floor or Rooftops Roof-top roof of the building. The opportunity to lay the building or premises communication ducts, pipes (especially in the renovated buildings). 2.3. Fire protection requirements for categories of premises Normal - premises category "D" or inflammable "B", or explosive "A" and "B" and corresponding to these categories of design decisions (reverse and fire retarding valves, separate blocks installation of equipment, various schemes of laying communications ). 2.4. Operational requirements permissible maintenance and management system with a central control or you need to manage (adjusting parameters) independently (for example, when one part of the premises is oriented to the south, the other - to the north) and the need for separate modes of operation of the equipment on the premises of the group. 2.5. System reliability are especially important requirements for reliability in a precision air-conditioning at the exact maintenance of microclimatic parameters of various technological processes. 2.6. Economic requirements necessary to optimize the cost, comparing the project equipment from different manufacturers and different classes. For objects, you need to develop some policy options based systems of various types of equipment and carry out their comparative evaluation. 3. Stages of design work Designing SLE is mainly in two stages. 3.1. Stage 1 - Project Feasibility Study (Feasibility Study) At this stage of design, with aggregate produce selection and feasibility study of the type of system, determine the technical area for the installation of this equipment, as well as the definition of a first approximation, its main characteristics: performance Air, heat and cold type and number of central or air conditioners, their location, type and flow of heat and refrigerants type and number of chillers, pumps installed capacity of electric mass of the system In this case: Establish preliminary cost systems are developed in principle (pre-) scheme of the system previously in the practice of design for the stage of feasibility study followed by a technical project. With the advent of block equipment, these two stages are combined and are now in the practice of designing organizations is a feasibility study. As commercial firms it is - a technical project. After approval by the Customer feasibility develop a working draft - it's the most responsible stage of design. 3.2. Stage 2 - detailed design is developed on the basis of: Construction of lay-thermal characteristics of building structures of Technology (detailed specification) tasks at this stage: calculates teplovlagovydeleny and on its basis the calculation of ventilation for each room, providing the required parameters. Pick up equipment (with all characteristic), which provides the necessary air Determine the head loss in the network finally choose the type and the conceptual framework of the system and determine its characteristics, the number of diffusers, etc. Draw the plans with the application of the location of the equipment and wired networks, ductwork and piping Next: Damn axonometric scheme of network of ducts and pipes Perform aerodynamic and hydraulic calculations is determined by the noise level is filled specifications for equipment, materials, fittings, etc. with the manufacturer's instructions and the cost of the project after approval by the customer in the SES and fire inspection, if there are comments on the draft, make corrections based on the documentation to produce custom hardware at this stage of design finishes. Working drawings are transferred to the object assemblers. After completing installation work plugged on organizations prepared as-built drawings and executive specification.
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