Hi there. The fan on my Beko CDA543 fridge freezer runs constantly resulting in frost covering the top half of the back of the refrigerator. If I turn the fridge freezer off and on at the mains the fan stays off until the temperature rises enough for it to kick in again, but then it won't turn off until I reset everything by flicking the mains again. I suspect the problem is the "irreplaceable" sensor located in the insulation at the back of the fridge wall. I have seen a hack on how to access this and would like to replace it by cutting a square from the insulation t. Is it possible to acquire a compatible sensor or do you think something else may be causing the problem. Many thanks