I have a GE fridge, model no. GTS20ICNCWW. We recently woke to a melting freezer. The fridge works perfectly fine. I can still hear the normal freezer sounds, and all of the lights work, but there is no cool freezer air. I let it sit unplugged for 24hrs after cleaning it out as best as i could in the lower back area. The top freezer is still busted. Could it be a compressor issue? If so, could a novice diy-er replace it?