I realize this is an old post but hope anyone looking into Accuweld windows might come across this. Installed Accuweld windows (three twins and three singles) and one 9'sliding door.
First winter ice formed on the sliding door (inside for the record). The fix by the service manager at Accuweld (named Bill) was to jam velcro in the gaps of this $2400.00 door. It didn't work. The velcro worked it's way out from opening and closing the door. He did offer to mail me more velcro though
The frame also warped over time. When the slider was left open on a hot day, it would warp and you could not close the door without the slider banging against the stationary pane.
All of the "factory" mulls on the twins warped and allowed enough cold air to come through to form ice on the mullions. No response from the Accuweld service department. Several of the glazing strips bowed out and shrunk. In a conversation with accuweld service department, they indicated that they would get back to me when they could come out. I never heard from them again.
They wouldn't even respond to Lowes which sold the windows and doors. The salesman told Lowes that he wasn't very concerned if Lowes stopped buying from Accuweld. Basically the company and the products they produce are crap.
Accuweld refuses to stand behind their windows and door with Lowes. Lowes agreed to eat all of the windows and supply any window of choice to rectify the problem.
If you are considering Accuweld, save yourself the headaches. The sample looks GREAT. I wouldn't install their windows in a doghouse though.