The exhaust system on your Aqua-Hot is made with automotive type exhaust pipe. As stated, ANY muffler shop can easily manufacture a replacement exhaust pipe for your coach.
Exhaust is setup like the drawing shown in attachment.
Make sure that the 1 1/2" standard plumbing pipe fittings that thread into the bottom of the Aqua-Hot are not damaged. If they are, they can easily be replaced with 'standard' black threaded pipe.
If you have to remake the entire exhaust, then I would recommend 1 3/4" ID pipe (or larger). The larger pipe will make your Aqua-Hot breathe much better.
Carefully check for coolant leaks. Sometimes damage like this will damage the metal boiler tank and make it leak.
You should not use the diesel burner on your Aqua-Hot until you get the exhaust repaired. You may use the electric side with no limitations.
- Roger Berke -