7 卫生间通风设计
本工程房间的卫生间设机械排风装置，设置排气扇，卫生间的通风换气量按20-30m3/h。无窗卫生间设置排风口，由排风机排至室外。靠近外墙且有外窗的卫生间，直接排到室外。卫生间保持负压，防止气外泄，卫生间选用排气扇加止回阀。
The general illustrate of design
1 The source of the design
With the progress of the times and the improvement of people's living level, the air conditioning has become an indispensable part of human life, air conditioning technology is widely used in people's daily life and work places, We cannot live without it whether residential or public buildings, it makes our life more comfortable.
This time is through the design practice of Shanghai Tiantong building, according to the study of basic theory and professional knowledge, combined with the practical engineering, according to the building plans, in accordance with the engineering design specifications, standards, technical measures, design drawings and relevant references, independently complete the design of air conditioning system, master the selection and layout of the wind pipe, water pipe and equipment of air conditioning,; master the calculation of wind and water pipes; reinforced drawing ability; cultivate the ractical engineering application ability to analyze and solve problems, to lay a good foundation for future work.
Modern humans spent most of the time in building.People have realized that architectural environment plays a very important role in human life ,work efficiency  and product quality. With the development of social productivity, air condition and human beings live and work required in the production process of the required air state under the condition of continuously improving the air conditioner, and obtained the very big development. Therefore, with the improvement of people's lives, air-conditioning penetration rate is increased. So for large public, civil construction and some special facilities, air conditioning is indispensable.
2 The general situation of the engineering
Tiantong building is a large comprehensive building, located in the urban area of Shanghai. The building has three layers.The first floor layer is 3.6 meters high, the other two layers are 3.3 meters high. The first layer, the integrated office, including the Department office and clinic, two layer three layer are offices, layout similarity. Roof roof with a staircase. System selection is not complex, construction is convenient, the summer air conditioning and heating in winter with the use of the same system, whether from the perspective of economic, life, or from the beautiful, clean, in accordance with the construction application requirements.
3 The basic of Design
3.1 Design task request and the original information
According to the Building nature, purpose and requirements of the construction, for the Beijing west mountain mechanical motion Co., LTD, we make the planning of the office as follows:
⑴    load calculation(mainly on basis of cold load calculation).
⑵ air conditioning wind system design: according to the actual situation of the construction of the system to choose a suitable.
⑶ cold and heat source equipment design(select appropriate cold or heat source equipment, cooling water pump, frozen water pump, fresh air units of design of type selection, water pider, catchment device design calculation, and determine equipment installation position and piping layout).
⑷ the calculation of air-conditioning Selection: including the choice of fan coil, air conditioning units and air units of the new calculation Selection.
⑸ air conditioning water systems and wind systems design and calculation: including water piping system design, fan coil units and air-conditioning layout.
4 The main design work
According to the characteristics choose air conditioning mode; calculation of cooling load; wind pipe and water pipe layout and hydraulic calculation; list each pipeline hydraulic calculation table. According to the hydraulic calculation to choose air-conditioning equipment, including air-conditioning, fresh air units, fan coil, air and other equipment. 大型公共建筑中央空调系统设计说明书(2):http://www.youerw.com/gongcheng/lunwen_3375.html