Need Appliance Repair Help? Ask a Technician for Answers ASAP
Unfortunately it sounds like your unit is just not defrosting on it's own like it should anymore. You'll need a multimeter to test and determine which part has failed for certain. To test, unplug the refrigerator and pull everything out of the freezer section. Remove the screws going into the lower back panel to expose the silver evaporator coils where all the frost is forming. There is a 1" device clipped onto the top of the silver coils with 2 wires going to it---that is your defrost thermostat. This is the most likely part to fail so if you have a multimeter, test continuity through this defrost thermostat and the defrost heater below the silver coils. If either part doesn't have continuity, then replace it. If they both check good and have continuity, replace the defrost timer at the top of the refrigerator section in the control panel cover.
Now if you don't have a multimeter, I'd just replace the defrost thermostat as that is by far the most likely part to fail. Below is a link to the part.
CLICK HERE for defrost thermostat
We are on the honor system here. Please remember to rate my service by selecting a star at the top of the screen before you leave today. If you need anything else, just let me know. You can continue asking follow-up questions at no additional charge after rating my service if you still need assistance.
Hello again. I'm just following up because I haven't heard back from you and I see this question is still open. Is there anything else I can help you with?
No problem I'm glad I could help. Please remember to rate my service by selecting a star at the top of the screen before you leave today.