Water dispenser would not fill a glass completely

The trouble with DIYers is that they don't have very much experience with and the benefit of several repairs on the same appliance. So they must rely on their mechanical abilities and the youtube help of Steve. So they must resort to eliminating the variables as their diagnostic approach. In my case I was unable to find the exact description of my problem, so I began with what seemed like the most likely and the least expensive replacement. So after I had replaced the water valve, the micro switch and the main board I finally found the problem was the water filter by ordering and installing a water bypass valve which I did not have readily available at the start.