Suburban Furnace Recall

I just purchased a used Skyline Weekender truck camper. When I went to see it and he had the heater running with the door of the camper so I didn't think anything of it. When I got it home I tried out the heater and it took many times to start. The flames kept going out. Everything I read on said to clean it out and check the vents. So I took the unit out and to my supprise there was no exhaust vent. The Suburban heater has the pipe in the back and there is a hole in the inner wall but inside the hole was insulation and no hole going outside. I assume this is why the unit didn't want to stay lit because there was no place for the exhaust to go. I am not sure at this point if he had siding work done and it is his fault or if it is Skylines fault but I will find out soon.
Todd