An electric water heater is a device that helps to minimize the cold of the winter. Water enters the tank from the side marked 'input'. The electricity resistant elements placed inside the tank heat the water. The hot water is stored in the tank until required. The installation process is not difficult, but it involves some electrical work and plumbing skills. If you are doing it for the first time, then you must plan the process on a paper first and make a checklist of the tools and parts required so that you have everything handy before you begin.