"Micro Cooling Fan" means a method to solve the pump system and method of the same working conditions, working conditions illustrated fan unit is still the method now widely used. Fan P-Q curve showing the relationship between the energy and performance of the fan flow to the unit volume of gas supplied; "Micro Cooling Fan" line P-Q performance curve showing the relationship between gas flow required per unit volume of the piping system and the flow of energy, which is curves of two different concepts. However, "Micro Cooling Fan" fan unit, the two curves and interrelated, mutual restraint, the device is mass-balance conditions that result fan and piping; also a fan and piping energy balance results.