I have Samsung RS2545SH for 6 years. The problem started by filter water not being dispensed. a month later, the fridge started making fan noise. One friend suggested to unplug and let it defrost. we did it and the fan noise stopped for 2 months but water froze the next day. After 2 months, the freezer side stopped working. we called appliance repair shop, the tech, opened the back panel, all iced up, so he de-iced it, changed a thermostat in freezer side, and put back everything. next day filter water froze again. we called and he returned, this time changed water tank heater. and another thermostat in fridge side. next day water froze again. he returned and suggested to change control board. we did, but no help. still water tank freezes and probably ice is being accumulated on the condensers.
the tech is clueless, anyone have any suggestion what other part needs to be changed? I read online about bi-metal that controls the defrost, should I change that? Please help if have any experience with this kind of problem 