Hi, I have 7 north facing 40 year old Anderson double hung windows. One lower sash constantly has condensation on it, winter or summer, on the inside. None of the other windows have ever had any condensation on the inside. The blinds are open and there are no curtains to block air flow. It is only the lower sash not the upper. It is the second story window with windows above and below it. Any ideas why? Thanks, Mike
