I went to youtube and discovered the cause. I bought a new thermostat, defrost sensor, and the heating element and added a metal clip from the heating element to the water discharge hole. It still wasn't working correctly and I had an appliance service rep to come out. They suggested I purchase a new back panel (that included a new fan) to the frig along with discharge tubes. That solved the problem. All parts cost approx $250 and I saved a refrigerator. I saved approx $600 from an appliance repair company. It is not that hard to fix once you know what to do.