摘  要:本文详细介绍了别墅空调系统-风机盘管加新风半集中式空调系统的设计，论述了这种空调系统的原理及优缺点。先进行负荷计算，再设备选型，绘制系统图及进行水力计算。风机盘管加新风系统由两部分组成。一是按房间分别设置的风机盘管机组，其作用是分担空调房间的冷、热负荷；二是新风系统，通常新风经过冷、热处理，新风机组仅负担新风负荷，以满足卫生要求。

风机盘管加新风系统借助风机盘管机组不断地循环室内空气，使之通过盘管而被冷却或加热，以保持房间一定的温湿度。盘管使用的冷水或热水，由集中冷源和热源供应，与此同时，由新风空调机房集中处理后的新风，通过专门的新风管道分别送入各空调房间，以满足空调房间的卫生要求。

风机盘管空调系统与集中式系统相比，没有大风道，只有水管和较小的风管，具有布置和安装方便，占用建筑空间小、单独调节好等优点，广泛应用于温、湿度精度要求不高、房间数多、房间较小、需要单独控制的舒适性空调中。但机组分散设置，台数较多，维修管理工作量大，水管路多，控制精度低，易发生凝结水渗漏事故。

关键词：新风，风机盘管，负荷计算，设备选型，水力计算

ABSTRACT:In this paper, the villa air-conditioning system, namely the primary air fan-coil system of the semi-central air conditioning system is introduced particularly. The principle and advantage and the disadvantage of the system are also discussed. The procedures of the design of the primary air fan-coil system are load calculation, type selection of equipment, sketch of the system and hydraulic calculation.  

　　　Two parts constitute the primary air fan-coil system .One is he fan coil which takes on the cooling and heat load of the room. The other is the fresh air system by which the fresh air is disposed, which merely takes on the load of the fresh air to meet the demands of the sanitation.

　　　The indoor air is continually circulated by the fan coil units to be cooled or heated by the coil to keep the temperature and humidity of the room to a certain extent. The chilled and hot water used by the coil is supplied by the centralized cold and heat source. By the same time, the fresh air disposed by the fresh air conditioning plant room is blasted by the special fresh air duct to meet the demands of sanitation of each air conditioning room.

　　　Compared with the centralized air conditioning system, the primary air fan-coil system has no large air duct but water pipe and smaller air duct and possesses the advantage of easier assignation and installation, less architectural space and better separate adjustment. As a result, it is widely adopted in comfort air conditioners of lower demands of temperature and humidity, larger numbers, smaller space and separate operation. However, due to dispersed assignation and large numbers of the units, the primary air fan-coil system has larger quantity of maintaining work, larger numbers of water pipelines, lower controlling precision. As a result, condensate water accident is easier to occur.

Keyword: fresh air, fan coil units, load causation, Type selection of equipment, hydraulic calculation