My Candy fridge compartment ices up with in a week, this blocks the drain hole,(which I make sure is clear.and that water flows down it.) I have fitted a new thermostate. I keep a thermostate inside and this shows 6deg.
6 Deg. what? Celsius or fahrenheight. If 6 Deg celsius then the thermometer you put inside the fridge is inaccurate because water freezes at 0 deg so inside the fridge must be at least 0 deg celsius for it to ice up. I would say that the thermostat you fitted is either the wrong one, or is faulty or you have installed it incorrectly.
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix refrigerators.