My initial plan to vent the fan exhaust out the top of the clset by cutting a 4 inch hole for a vent was foiled when I found out it is solid wood through the whole header above the closet. SO for now I run the duct like this and close the closet door just enough as to not block the airflow. If I'm home I just leave the doors open and extually use 2 small turbo fans to blow fresh air into the upper room from the floor and pull air out of the bottom room with same type fan. With duct fan 147CFM pulling warm air off the light and the 2 $10 turbo fans from target my closet is maintianing 78 degrees and 58% humidity. If I closer the doors except not to block the duct fan exhaust my closet gets up to 84-88 degrees and humidty drops to about 40%.
