The American Architectural Manufacturers Association has a brochure how to properly maintain today’s windows and doors. The message is very clear, low-maintenance features do not mean these products do not need attention. “Caring for your Windows, Doors and Skylights” provides general information to help end homeowners get the most out of their fenestration products.
http://pubstore.aamanet.org/docs/Caring_for_Your_Windows_Doors_and_Skylights.pdf