After buying a Hotpoint Iced Diamond second hand fridge, I have discovered that after a week or so the fridge seems too cold, even on the lowest setting, and in operation the back plate semi-ices up, then is covered in droplets, and cycles through this routine over and over for about 20-30 mins. This seems far too frequent, is it that the fridge temperature control is faulty or the auto defrost function is not working properly.