This boat owner (and his neighbours) was extremely lucky that the cockpit of his boat was sealed airtight and the fire from this overheated dehumidifier smouldered and self extinguised due to lack of oxygen.  There was still suffiecient heat to buckle all the windows, melt fittings and cause smoke and smoulder damage throughout.  NEVER remove the catchment reservior from a dehumidifier to allow it to run into a sink as next time, we may not be so lucky!