Think the problem is due to icing up of the heat exchanger which prevents the air circulation into the fridge compartment. It is very common I think, but it could be one of several things which cause it (sensors, heater, controller pcb) and the difficulty is determining the faulty component.
To prove the point try the following if possible. If you are able to find somewhere for the contents, try defrosting the whole unit it for 24hrs with the doors open and mains supply switched off. You will probably then find that it all works correctly, but only for about 2-3weeks before it happens again. There is definitely a fault which needs correcting, it is not something that you can adjust.
The heat exchanger in the back of the freezer compartment gets very cold (obviously) and condensation/ice build up on it to the point where it becomes useless as air can no longer pass over it. The freezer is supposed to periodically switch on a heater located under the heat exchanger to melt the ice but this is not happening for some reason.
I'm still trying to get to the bottom of the problem with my unit (hence trawling these pages).
If you want to access the heat exchanger you can get to it from inside the freezer compartment but its a fiddle. email me on adrianleachuk@yahoo.co.uk if you want more detail of how to do this. At least this enables you to pour hot water over the heat exchanger to reduce the defrost time to about 1hr ao you food doesn't defrost too. But you still have to repeat every 3 weeks!!.
Good luck.
Adrian
September 2007