How can i fix my Samsung American Style Fridge Freezer SR-S2028CVW?

I have a Samsung SR-S2028CVW American Style Fridge Freezer. It has run perfectly well until recently, where it now trips the RCD as soon as it is plugged into the mains. I left it disconnected for 1 week changed the fuse, tried again and it operated for 2 hours before the freezer temperature kept on flashing at -20 and it started to defrost (fridge still seemed to be working), I then left it off for 1 hour and tried again, where it operated for around 8 hours, then unfortunately it tripped again - it trips immediately ofter plugging in now. No further error codes have shown up

Jonathan
September 2011