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Realization of dry dehumidification employing a cooling cycle (i.e. cycle-heating dehumidification operation), and further reduction in noise through use of skewed blades.

Photo of HVAC

A cycle dehumidification system making use of the features of independent cooling cycles has been adopted. Use of this heat pump reheating system ensures that there is no sense of excessive cooling and makes it possible to economize on energy and to reduce the weight of the unit. In addition, use of skewed blades for the external propeller fan and optimization of the blade angle of the internal sirocco fan has made it possible to reduce noise levels to 63 dB outside the cars and 64 dB inside the cars in comparison with our previous values.