The new unit is a replacement for one that was already in the home we acquired in 2011. When the original unit started acting erratic we purchased a new one which I installed. The installation was very easy. The hole in the counter top fit the new unit and the screw mounts for the tank underneath were the same on the new unit. Hoses are a pop-on fit. All I needed was to remove the garbage disposal to gain access. Unit was quickly up and running...hot tea, etc.