Serial number 9911128730. This Amana side by side is about 8 years old and has never had any problems, nor has it been moved or abused. I first noticed the freezer unit stopped making ice. Then I noticed a continual increase in freezer temperature over a week long period. The condensor coils under the fridge are completely clean and dust free. The compressor is running, and does not make any unusual clicking noises or cavitation noises (a low on freon symptom), and is not hot. The cooling fan in the back of the unit is running at full speed and is not an issue. So I pulled the evaporator coil cover inside the freezer expecting ice buildup (from all the other posts I've read). Nope, no ice, in fact no frost or ice on the whole coil. There is about an 1/8" of frost buildup on the coil just before the clip-on defrost thermostat, but no frost after that. The whole coil is cool to the touch, but not cold by any means. See the pics attached. I felt the defrost heater and it's not on, nor are the walls hot or anything abnormal. My first thought is that it has lost freon, or the compressor is not working right, but the compressor runs like a purring kitten, and I don't hear any line cavitation or sucking sounds, or anything abnormal. The evaporator fan turns on and off normally over time, which I know is controlled by the defrost thermostat. Any clues??

I was thinking that might be the response. :( If it leaked most of the freon should I be able to find a greasy or oily joint somewhere on the copper lines? I'm mystified that a fridge that is only used as a beer box, can suddenly lose all the freon and still sound completely normal. Thx.