Samsung French Door Refrigerator only 4 1/2 years old. For the past 1 1 /2 years the Evaporator fan hits ice build up in the Refrigerator compartment. Every 6-8 weeks this has happened. Have replaced temp sensor 3 times, defrost sensor 2 times, control board, and heat element during that time line. Have also increased the defrost time from 20 to 30 minutes, and still have the same problem. Every time I call Samsung Tech Support and explain what is going on, they don't know and have never heard of this problem. Hello, check out the complaints filed against Samsung for this issue. They have recommended replacing these parts. Fed up after spending $2,000 for this piece of -hit product, I find out 3 weeks ago Samsung issued a service bulletin on how to fix this problem. Heat from the condenser unit is traveling up through the drain tube and entering the Evaporator area causing ice to build up by the Expansion Valve making the fan blades hit the ice. Defrost mode will not melt this ice. Refrigerator has to turned off all day or over night, unless you know how to take to Evaporator cover off and use a heat gun to melt the ice. Try doing that every 6 weeks for 18 months. Samsung has basically admitted to this problem by putting out an updated Drain Repair Kit which now eliminates warm air from traveling up the drain tube into the evaporator and causing ice build up. Install this 2 weeks ago and am sure the problem is corrected. Now i am fighting with Samsung to get my money returned for the parts that were installed. I am a retired Refrigeration Tech and knew warm air was entering, but could not figure out from where. Have spent 9 hours on the phone with Samsung over the past 3 days, have sent my receipts 3 times, proof of my Refrigeration Certification, and pictures. Called today to verify if they finally received them and after waiting 90 minutes for my call back I got disconnected. Now waiting for another call back. Their customer service and tech support totally suck. Never buy a Samsung Refrigerator!!!!!!!!!!!!!!!