Humidity control utilizing heat pump concept

摘要

A vapor compression system for allowing humidity control includes a plurality of vapor compression circuits including at least one cooling circuit and at least one heat pump operable circuit; the plurality of circuits being adapted to act upon a stream of air whereby a first portion is cooled by the at least one cooling circuit and a second portion is heated by the heat pump operable circuit whereby the stream of air can be dehumidified while maintaining a desired air stream temperature. As a result, such a system can have three modes of operation; cooling, heating and dehumidification with low sensible capacity as well as multiple steps of unloading. Furthermore, system reliability and complexity are improved and operation and control functions are enhanced.