The 3rd technique is referred to as jet ventilation and utilizes the fact that a transferring system improvements velocity when it truly is subjected to the "pushing power". In physics, this phenomenon is named thrust. You should buy an air exchanger similar to this Tjernlund X2D Reversible Basement Admirers from https://basement-ventilation02344.blogdanica.com/36475133/new-step-by-step-map-for-car-park-ventilation