My chimney drafts too hard in these cold spells.. The baro was unable to keep it under a .05" WC. I found that by using a combination of a the MPD and the baro, I could achieve a steady .03 WC" in any strong draft situation
Given the present weather conditions, I too am considering a mpd, I have about a 4 ft. diagonal, about 70 degrees in favor of vertical and then bull nose baro going into 1 ft. section to chimney, would the mpd go before or after baro? Of course I won't do until milder weather, everything is running good.