If you have bad door seals, the frost will have a finger from the door to the rear. Since the frost is on the back wall, you have a NORMAL "problem". The cause is the humidity in your location. Also how often you open and close the freezer door's. The only remedy is to defrost when the frost builds up. Remember, Frost/ice is a great insulator and diminishes the transfer of heat and cold. When you have ice build up on the lower section on the Evap fins, THAT diminishes the cooling capacity of the lower section, hence you need to defrost THAT section when ice builds up also. Doug
PS how long does the frost take?
