When I do furnace tune ups, I sometimes run into people who have gotten a new mid or high effic furnace and they say that they now have big humidity probs where there was none before the install of the new furnace.

Can anyone give me some reasons for this other than changing the structure or integrity of the home? When customers ask I would like to give them some answers for this or possibly solve the prob if it is a simple solution

Thanks in advance

don