Problem: My brother has a drum humidifier on his furnace and is quite satisfied with it, so I installed one on my furnace this fall. He claims it is a good idea to partially close the damper for winter operation - he says, "if the damper is open all the way, the furnace has to run longer to heat the house because so much hot air is being sent into the cold air duct." I don't know if I agree with him, but perhaps I don't understand what he is driving at. All the information and instructions I can find only talk about "open" and "closed" positions.
Question: Can anyone comment about partially closing dampers for humidifier operation for winter?