Gilligan's Power Washing offers Exterior Window Cleaning using a Water fed Pole with pure water to leave windows clean and streak free.
The Technology Behind It
Water in its purest form (rainwater, depending on the pollution where you live) has zero Total Dissolved Solids (TDS) in it. Purified water is well known to be a great cleaning agent for many applications such as cleaning clothes and taking showers. Those of you that have children more than likely have bathed your kids in purified water, and of course mix the baby formula in it as well.
Pure mineral free water naturally wants to bond with minerals, dirt, and organic material. Its all part of the natural cycle that our planet produces. So when water passes through carbon, sediment and RO filters, then on to DI resin it is nearly as good as rainwater in purity (with regards to mineral and some chemicals that have been removed from the water).