My Samsung refrigerator freezes up on refrig side. It has separate condensors so freezer is fine. The first sign of problem is water dispensor freezes, then refrig gets as high as 50 or more. Replaced defroster, water heater, defrost sensor and temp sensor and it still does it. Works for a while after I defrost it. Authorized repairman for Samsung said it was defroster and it would have been hundreds of dollars for him to fix since he would have to cut freon lines to replace whole coil unit with defroster. I replaced old deforoster with new by just disassembling defrost unit, but it still freezes up. The temperature on the front door reads 33 or so since it is embedded in ice when it freezes so it makes one think all is fine. An additional fan to move more air seems to fix problem, but I have to run it and stop and run and stop since the fan itself creates some heat. Is a there a replacement fan that i can get that move more air volume to fix this? Samsung gives no advice or help and many others are having this same problem. Thanks
Problem is possibly ice build up on evaporator coil. The defrost heater could be burnt out. This can be determined by checking for open circuit across the leads to the heater. It unplugs so you just use an omnmeter to see if there is resistance in the heater.