A tenant called me regarding water in her dryer whenever the other tenant in the duplex did laundry. She said it's been happening ever since she moved in six months ago (this building's only been ours for six months).
Water in the dryer? This was a new one. Well what I found is that the laundry rooms back up to each other, and that two dryers have exhaust hoses that connect together, then to a single vent outside through about a six foot length of vent hose. When one tenant uses their dryer, part of the moist air goes back into the other dryer where it condenses and leaves a pool of water.
I thought of using two of those draft blockers, one on each section of hose before it reaches the Y connection, but I was worried that if both dryers are running at the same time that the back pressure will keep one or the other from opening.
Running another vent hose out the wall is another option I guess. Is there a hole saw for a 4" vent, or how do you cut a clean 4" hole through stucco?