it is a common fault with the several parts that fail. i believe its the defrost heater, defrost sensor and others. This is a common fault for ALL of these fridges and SAMSUNG will repair for free. It was on Watchdog late 2009. Good luck
Andy
July 2010
Completely defrost then restart. There is a fault with these. If problem reappears call Samsung, they know about the faults and have extended the warrenty to 5 years. Look up watchdog Samsung rs21 for details
alsabhoy
October 2009
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