Are the concrete walls bare? Is the humidity outside the room "high." Could water be condensing on the walls when the door is open and then raising the humidity when the door is closed again? If so then add another dehumidifier to the room outside the vault. An alternate solution would be to either insulate the walls or build an "air lock" to minimize intrusion of room air. Even monitoring the humidity outside and only open the door when the outside air is less humid. > >On Wed, 18 Nov 1998, Patricia McElyea wrote: > >> Hi All!! >> >> I desperately need your help and advice! Here is my situation. I >> have a 200 sq. ft. vault area, concrete construction on an out side >> wall. Controlling the humidity in this area has become the bane of >> my existence! I run a dehumidifier constantly and check it twice a >> day. I have adjusted the temperature, contacted the AC/Environmental >> department to check it....Seems no matter what I do there are still >> humidity spikes (sometimes a much as 20% in a week). The kicker is >> that I literally have NO BUDGET to deal with this. Any >> suggestions??? >> >> >> >> Patricia McElyea >> Curator of Collections >> Arkansas State University Museum >> [log in to unmask] >> END end ************************************************** Douglas W. St.Clair Tir Na Nog 400 Burton Highway Wilton. NH 03086-5022 PH: 603-654-9321 FAX: 603-654-5440 EMAIL: [log in to unmask] WebSite: http://www.tellink.net/~dwstclair **************************************************