ehenam nam na but positive pressure ekak hadena widiyata fan install karana eka hodai kiyanawa dust adu wenna.
eg: 3 fans case eka athulata hulan adinawa, 2 fans case eka athulen eliyata hulan adinawa.
ethakota athule pressure eka wadi nisa duwili radenne nathuwa eliyata yana fan deken duwuli eliyata yanawalu