One of the most common causes of water leaking from a dryer is a blockage in the ventilation hose coming out of the back of the dryer. A clothes dryer generates heat, which must be able to exit the machine, or condensation can form inside the drum. I… water coming from a dryer may be the result of a non-insulated ventilation hose running through varying temperatures as it leads hot air from the dryer to outside the home.