For some reason, there is much dust gathered in the air conditioner's input draught, output draught, fan and evaporator during the using of the indoor unit of the split type air conditioner.

分体壁挂式空调室内机在使用过程中，由于种种原因，空调进风口、出风口以及贯流风扇、蒸发器上会聚集较多的灰尘。

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There's a second alternative: A growing number of New Yorkers are going for duct-free AC systems that involve a small, wall-mounted indoor fan powered by a separate outdoor unit the size of suitcase.

WSJ: Ugliness for All