I have an electric combo stacked washer/dryer (probably 20 years old but rarely used). While the washer works great, The dryer above does not fully dry the clean clothes. The dryer tub gets hot and it "spins", the removable lint trap is kept clean, but even at 50 minutes on hot, most of the clothing is still pretty damp. I do not overload the unit. I checked the venting ductwork in the basement and I can feel hot air running through it and I see steam outside coming from the vent outside. If I use a no heat setting, the condition is worsened. Do you have any ideas?