This is clearly NOT a do-it-yourself project, but the video is intended to show how a highly-efficient Rennai Tankless Water Heater is installed by professionals.
This Rennai Water Heater represents the next generation of smart, energy saving, on-demand water heaters, which use less energy and are far more efficient than older models.
The purpose of the video was to not only show the installation process, but demonstrate the kinds of new energy-saving household technology available today. Part of this was illustrated with animations by David Masher.