Hello Folks, this is Rich from Western Appliance Repair in Meridian Idaho. Thank you so much for reading my blog of appliance repair services. I hope to keep these blogs informative to aid you in your DIY repair projects.
Here is a picture of an evaporator on a Frigidaire side-by-side refrigerator. On this type of refrigerator the evaporator is located in the freezer behind a panel on the back wall.
What is unusual in this instance is the ice forming in the lower part of the evaporator. This ice buildup can be confused with other similar but different problems if not analyzed closely. This first thing we consider is if the defrost water drainage is good. In this case we have to consider it is since usually the water will overflow the drainage pan and flow out onto freezer floor. Can this be a defrost problem? No, with a refrigerator defrost problem you will see uniform layer of thick frost across the whole evaporator. This is not so.
Here what we actually have happening is a sealed system refrigerant fault. The front facing half of the evaporator is cooling properly but the rear half is warm. The rear part, which is hidden so you have to look closely, is forming condensation which constantly drips into the drain pan. Since the front half of the evaporator is sufficient for the cool/freeze function, it freezes these drops of condensation quickly. This forms what we see here, a large chunk of ice on the bottom section of evaporator.
This ice will eventually choke off all airflow to the Fresh Food side of refrigerator.