The contact owns a 2017 Forest River Brookstone RV. The contact stated while the vehicle was parked he and his family were in the trailer. The contact smelt something burning in the trailer. The contact inspected the trailer and noticed the burning smell was coming from the heater ducts in the trailer and had melted due to the material of paper and Styrofoam in the heat duct to extremes heat coming from the furnish in the trailer. The contact took the vehicle to a local dealer who diagnosed the failure as the contact expected was extreme heat coming from the furnish that caused the heat ducts to melt. The dealer disconnected the furnish from the heater deck, however the vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 250.