Pella Windows and Doors

The installers did a fine job as well as the salesman. The windows themselves are fogging up during the winter months on the very inside around the edges, where the glass and the wood frame fit together. They also freeze when temperature gets low enough. These were brand new windows when installed in August of 2012. They have had this issue all along. I have measured the humidity inside my home and it is normal, and always below what is listed in Pelle's condensation information sheets. I have 11 other brand windows that don't fog up at all, it is just the Pro-Line windows that have this problem. I'm worried that the wood frame will rot from the inside out of the window pane. In reference to Pella?s response, I would like to correct several misstatements: First, there was no mold on the old windows, just a little normal light scum on the glass, which my wife cleaned off in a minute with Windex. From my datebook of 2014: Feb 17: Outside temperature 40 F. Inside humidity 31%, ( shown on two of my humidity indicators) which is 9% below Pella?s maximum recommended level for that outside temperature. From my 2015 datebook: Feb 10 (Not 11): By the time Pella people arrived, outside temperature was + 40 F, and inside humidity was 36%, indicated on both of my meters, well under the recommended level. My humidity meters all indicate 5-6% lower than Pellas meter. The Pro Line windows have the moisture problem most mornings when outside temperature is low, like-20 to 25 F, not at 30 F. It was right at 40 F both times Pella reps came, so they didn?t even see the problem. Also, from my 2015 datebook: Feb. 12: Outside-2 F at 7:30am, Russ Hohn, Member services manager of Oahe Electric Cooperative, brought infrared camera, which indicated temperatures of 8-10 F lower on sash frames of Pro Line windows compared to competitors window.( which never has moisture). Regardless of Pella?s claims, three facts remain: only the Pro Line windows have the problem; their glass is colder in winter. Our inside humidity is below Pella?s maximum recommended level.