Thanks for your replies, its been about 3 weeks since I last defrosted and the fridge section temp is slowly rising from 4C to 6C. Problem is the display says that it is at 4C but my digital thermometer inside says its at 6.2C. Once I have done a full defrost digital thermometer reads at between 3&4C for a few weeks before it starts to increase again. Bread in the freezer is the first thing to start to go soft meat remains solid.
The evaporator is iced up fully and I notice it runs for longer to try to pull the temperature down. I have now bought the part http://www.ebay.co.uk/itm/140751429164? ... 26_rdc%3D1
which says Manufacturers code is 502023500 which I hope will be a straight unplug & swap from the back of my freezer electrical compartment.
Kwatt further up said that its wishful thinking hoping its the sensor at fault and its normally the control pcb - surely if it works fine for a few weeks and everything is held at the correct temperature quite accuratly that says the pcb is functioning? The freezer is also at the correct temp during this time also. The temp slowly starts to increase from say 3/4C then goes upto 5C - 6C then 7C perhaps 2/3 days (as the evaporator ices up more) before each degree of temperature increase.
The only other thing it could be is the defrost heater? Hoping it isnt though as I know this cannot be replaced as its part of the evaporator. In your experience should the sensor rectify my issues based on the symptoms. Its just with what Kwatt has said about them very rarely failing... I also came across this forum post... http://www.howtomendit.com/answers.php?id=106888
which seems to suggest it is the probe that fails however a few people have said after a few weeks of replacing the sensor it is freezing up again. But works ok in those initial few weeks so if that is the case for me would it be the PCB or defrost heater?
Its obviously not worth spending £80 on a new PCB when I could possibly get a new replacement for £350... can you reccomend a suitable replacement. I would prefer frost free though.