I have an Electrolux Icon french door refrigerator left to us by the previous apartment owners. It has no model/serial sticker on it and they told us it was a gift from a relative.
After two years of use the temperature in both, cooler and freezer compartments started to fluctuate, ice began melting and 'High Temp' alarm would go off. But then the temps would suddenly go back to normal i.e. -20C and +1C cooler and freezer respectively, as if nothing happened before.
I used a portable temperature logger to record the temperature and got a constant seesaw every 2 hrs temperature goes up to almost +10C then briefly drops to normal (-20C freezer / +1C cooler) and immediately starts creeping up again. Once every a 24 hrs there is one longer 4 hrs cycle.
I tried adjusting the temperature setting, but to no avail. What can be causing this and what can I do to fix it?
Cooler temperature graph: 
Freezer temperature graph: (for a different day) 
UPDATE
The refrigerator stopped cooling at all. But I can still hear the compressor running. Virtually all the time.
Could it be that the refrigerant was leaking and now it has completely run out?
Best Answer
There may be list of reasons based on your refrigerator design. 1. May be a faulty pump that pumps coolant. 2. May be a faulty leaking capacitor in the circuit. 3. Leaking of refrigerator coolant. 4. Most power circuits have a ceramic round dial shaped capacitor that usually takes power surges when there is a sudden spike. After a few years(1-3) due to multiple surges it is subjected to a wear and tear and finally explodes. It happens many times and is located in coolant pump under a hard shell casing enclosed in hardened glue so that there will not be any visible damage. 5. There may be a leaking door as doors tend to loosen a bit on sides causing an air gap where cooling leaks.
Better call a technician as he can as sess and tell. I it covers warranty exchange for a new product.