Andersen Windows makes some fine products, but electric-powered, venting roof windows is not one of them. I bought four such windows in 1994. The gears of the roto-operators (both the pre- and post-1998) become stripped/dislocated within 5-10 years. In addition, the electric power operators don’t fit well onto the roto-operators and need adjusting every year or two. After twelve years of problems with these windows, I have now given up trying to make them operate properly.