Liebherr fridge not working properly

bob123

Hi

I have a Liebherr Kiev 2840 fridge.  It was in the house when we moved in but im guessing it is over 10 years old.  I dont particularly want to change it as it occupies a 

For the past week it is dropping temps on its usual temp.  I couldnt hear the compressor working.  Checked the gaskets for leaks and it is fine.  I had to increase the temp to max which seems to have kicked the fridge into action but now everything is getting frozen inside.  Ive done some reading around it and i think it could be the thermostat which is the problem?  I know its difficult but can anyone concur as im going to try and replace it myself.  Thanks