Due to their simplicity, fan coil units are more economical to install than ducted or central heating systems with air handling units.

由于其简单，安装风机盘管机组更经济比导管或中央供暖系统空气处理单元。

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First, most Chinese university dorms don't have any central heating systems or air-conditioning units.

首先，大多数中国大学宿舍没有任何中央暖气系统或空调设施。

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Owing to the complexity of the structure and the system of the new direct air-cooled heating units, a new question is arised about how to heating economically under operating condition.

新型直冷供热机组由于结构和系统的复杂性，其如何在供热工况下经济运行成为新的课题。

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Putting in new air conditioning or heating units that are much more efficient.

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Plants release moisture into the air alleviating the dry atmosphere generated by air-conditioning and central heating units, as well as computers.

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The expansion incorporates a fully-automated assembly line for air handling units and four production lines for ductless air-conditioning and heating systems.

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