nasa taas nya ng window? sarado ba yung window na yun? kasi kung bukas yun, disabled na agad ang exhaust mo. try creating an opening farther from the exhaust fan.
sa akin, dalawang bintana na sarado, bago pinto. so the vacuum created by the exhaust will suck air though my door, past the two closed windows, then out the other side of my shop's wall. the air current passes through my whole shop.