Thanks for the advice. They were very helpful over the phone. In the end it was the original service guy in Brisbane, Geoff Redfern from Caravan Refrigeration Services who diagnosed the problem as a faulty fan. This was after we paid $350 for a new black box which was not needed. However the fan is fitted and hopefully we are on our way this afternoon. The weather is not being kind - hope we run out of it. Thanks for the help. Looking forward to meeting fellow Kedron friends on the way around. Regards John & Lyn