Ice storage systems are an optional feature that can be procured and installed with many chilled water generators. Chilled water generators and their associated pumps provide cool water (actually a water-glycol mixture) via distribution piping to fan coil units installed within individual spaces throughout a building. This system provides conditioned air to a building, but through a distinctly different method than the forced cool air systems that most home-owners are familiar with. Fan coil units, as their name implies, are packaged mechanical devices that use rotating fan blades to push air across sealed coils through which chilled water is being pumped.