This invention discloses a dual-source, low-
dew-point, closed-loop water-cooled double-effect heat
recovery unit and its control method. The unit includes: a main circuit, a first
heat exchanger, a first three-way valve, a second three-way valve, a humidifier, a control module, and a second
heat exchanger. The main circuit includes a compressor, a four-way valve, a water-cooled
heat exchanger, a throttling structure, and an
evaporator connected in sequence. The control module determines the operating mode based on environmental information and regulates the main circuit, the humidifier, the first three-way valve, the second three-way valve, the first heat exchanger, and the second heat exchanger. Utilizing externally input
chilled water, the
system adjusts the temperature of the air output from the third chamber at the air outlet while simultaneously adjusting the return temperature of the
chilled water and outputting treated
chilled water back to the outside. This satisfies the varying indoor
heat load requirements due to different air supply temperature differences, achieving double-effect heat
recovery and solving the problem of
high energy consumption and large electric reheat requirements in dual-source, low-
dew-point applications, making the unit more efficient, stable, and simple.