Supply and installation of a new 50-gallon, 4500-watt Rheem medium-profile electric water heater, complete with drain pan. Installation of an expansion tank on the new water heater to accommodate thermal expansion. Option 1: Removal of the existing ¾" gate valve located on the right side of the home, to be replaced with a new ball valve and pressure relief valve. Option 2: Gate valve remains in place; only the expansion tank is installed with the new water heater. Needs to be permitted.