This symptom usually indicates that you have a frozen drain pan below the evaporator that is behind the back wall of the freezer. When the refrigerator goes into the automatic defrost mode, a heater around the evaporator coils will energize to melt the frost off of the cooling fins. The condensate formed when the frost melts is designed to drip down into a pan below the evaporator and then drain through a tube into a collection pan at the very bottom of the unit where the compressor is housed. The heat of the compressor and the air circulation created by the condenser fan will normally evaporate this condensate water before the next defrost cycle. If the drain tube or pan is frozen or clogged, then the water will collect in the evaporator pan in the freezer and will then overflow and drip down to collect in the bottom of the refrigerator. To check for this situation and correct it, you would need to unplug the refrigerator, remove the ice maker, take out the bottom floor of the freezer, remove the air tower on the inside back wall of the freezer and then pull out the inside back panel of the freezer compartment. With the inside back freezer panel removed, you could defrost and/or clear the drain so that condensate can flow to the collection pan below. Unless you are completely confident that you can safely complete this procedure, I recommend calling a service technician to fix this type of problem.
Instead of disassembling the back wall of the freezer, you can usually defrost this area by emptying the refrigerator and freezer, safely store the food, and unplug the unit for about 24 hours with the door standing open so that ice build-up in this area will melt.
In this model of refrigerator, the water fill tube for the ice maker will sometimes splash water into the area behind the inside back panel of the freezer and contribute or cause the above problem. If you (or the technician) see excessive ice build-up under the water fill tube for the ice maker, you may need to install a sleeve on the water fill tube to prevent this problem from continuing. The part number for the sleeve is 2203024. You can order this part from the Sears PartsDirect website
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