The new generation TWK-FD series heating air conditioning air anti-freezing control section is consist of air anti-freezing control and intellectual control.Intelligent controller can be designed into three types according to the different requirements of the users for fresh air. The first kind is wind control with internal circulation of fresh air frost control unit use. The second is completely into the fresh air anti-freezing regulation units use. The third is regulation of fresh air into the control unit by the fresh air quality use. Figure 4 is the air conditioning system schematic diagram of TWK- FD series for fresh heating air conditioning units and intelligent control cabinet. Figure 5 is the layout plan of TWK - FD series for supporting the intelligent controller cabinet.