My freezer has a temp that fluctuates from 3 F to 19f, food inside is almost frozen/frozen. Center wall on the leading edge is hot to touch at times, and not at other times. The out side wall on freezer side is warm. Like a being against a window with the sun against it warm. Inside freezer, both walls are cool to the touch. Temp in Fridge part is fine. So far I've replaced the defrost temp. About 20 minutes later I went in to check it and all was fine. Gave me the impression all was good. I went in a little while later and it got hot again. I see no other issues here so hopefully somebody has an answer. Thank you in advance.