To keep the electronic installation at normal operation, effective heat dissipation of the extremely crowded cluster computer room is needed. Usually, fans and air conditioning equipments are used to assist this heat dissipation work. In the cramped space of crowded cluster computer room, airflow is exceptionally disorderly. How to arrange the fans and the air conditioning equipments to make heat dissipation effective is an important problem. Using Computational Fluid Dynamics (CFD) software to simulate the airflow to find solutions for effective heat dissipation is extremely difficult. The purpose of this research is to apply neural networks model to establish a fitness function first, then, have this fitness function used by genetic algorithms in the finding of best approximate solutions for solving the problem of effective heat dissipation in cluster computer rooms.