Hello from Australia. Hopefully my fridge isn't completely foreign to you. I have an Electrolux Kelvinator N390SEJ-R (sometimes written without the R), that is giving me a bit of a headache.
About a month ago we found the fridge section was warmish, and we had a man out to have a look. He discovered the evaporator to be frosted up, and when we began to manually defrost it (pouring water over the ice) there was a slight hiss/sizzle, which he said indicated that the defrost element was still operative, and was in fact heating at the time. So perhaps this was just a one-off, caused by unusual environmental or usage reasons. Fair enough, made sense to me.
A week ago, we noticed that it was warm in the fridge again. This time, with my newfound frost knowledge, we defrosted it ourselves, and decided that we needed to keep an eye on it, because perhaps there was something actually wrong.
Today, one week since the last issue, we noticed the warmth in the fridge compartment again. I called the service man, and he said he'd be out in a few hours. He mentioned the defrost system as a possible issue, and I reminded him that he'd thought the element (heater) was ok last time. After I got off the phone, I went to the fridge and discovered that it seemed cold again. I rang him and he said maybe we should watch it for a few days, and get him out later in the week. I suggested defrosting it anyway, and he said I may as well. He asked me to notice where the bulk of the frost was, and I noticed that it was all over the entire evaporator, perhaps slightly more at the bottom. The defrost element runs along the bottom, and the fins on the evaporator are further apart on the bottom than at the top.
Since I put the panel back in, refilled the freezer, and turned it back on again, I have noticed that the compressor seems to be running without a break. The fridge is cold again, and the evaporator fan is definitely working (I can feel the air forced from the upper vents in the freezer). I was happy with the idea that the heater or timer was broken and was a simple replacement, but having the compressor running constantly worries me.
We tried a new ice cream about a month or two ago, and noticed that it was incredibly hard. We put it down to the different brand, but now, in light of all that has happened, it might also be that the freezer is working too hard as well. Inside temperature is very hard to judge with the proper equipment!
Hopefully someone can give me some ideas for the next steps in troubleshooting? Thanks in advance. Even if the fridge is no good, I'm glad to have found this forum!