Help, my Freezer keeps thawing out. I noticed that the coil was all froze up, but only halfway. The surface at the front doors was very hot. I cleaned underneath the freezer as it was very dirty with built up dust and lint. I replaced the defrost timer and about a week later the freezer did the same thing, Compressor off, food thawing out. I noticed that when i advance the defrost timer manually the defrost heater would kick on, but it only glowed on one side edge. a few days later the freezer was thawing out again. Below the defrost heater I noticed some ice build up. I dont think the heater was working. I took a hair dryer and after 2 minutes the coils were defrosted and the compressor kicked back on and started to cool. I replaced the defrost heater today and it will not get hot after turning the defrost timer manually. Is the defrost terminator bad? I dont have any tools to test anything. Please help