I had a repairman out the other day and he said my barometric damper was installed backwards so I had the company who installed it come out to look. This man told me that first of all, I don't even have a barometric damper. I have some kind of electronic damper. I have central heat and central air. He said barometric dampers are only used in conjunction with swamp coolers or something to that effect and now I don't know who to believe. He also said there is no "wrong way" to install a damper as no matter which way it is installed it still closes one way or another. Who is telling me the truth? The reason I had them out in the first place was that I have a 2 story house with a Zone system so have 2 different thermostats and when the upstairs thermo is turned off and downstairs is turned on it still blows upstairs. The latter of the two repairman told me it will always still blow some air upstairs and dampers don't close all the way and you would not want them to so in actuality some air will still seep around the vent.