According to the theory of indirect evaporative cooler, heat can be taken away through water evaporation by wrapping water absorbent film on the cooling surface of air conditioner condenser.

Indirect raw sewage water source heat pump system is utilized in this building for heating in winter and cooling in summer.

Now in China, the electro-magnetizers by indirect water-cooling are often broken-down, which hinders the improvement of the quality and quantity of Nd-Fe-B.