Does that back wall freeze up at all Steveo, It should freeze up then auto defrost. Does it keep your food cool, What I have seen a lot is people putting the shelves back in up side down, a lot of them have a bracket/stopper arrangement to stop you pushing your fridge contents up against the cold wall at the back. When the fridge then defrosts the water then runs down the cartons, packaging or whatever to the fridge and misses the drain. Supermarket salad bags are a favourite for that.