Hi, I wonder if you can help me, I have a samsung RS21 fridge freezer, that was repaired by samsung last year with the new defrost heater and both sensors, however I now find it has the same fault, I have carried out the checks sugested in your repair instructions with the following results. thermal fuse continuity ok, Drain heater shows 2.15 k, defrost sensor 8.5 ohms, but nothing on the middle which should read 480 ohms and no continuity, I presume from this I require a new main heater, can you confirm that I am correct and advise, many thanks Barry.