Eric,
Like Mike said, it sounds like you may have a problem with air in your fuel supply, but the Aqua Hot site that Mike referred to will probably not do you any good since your Hurricane system has very few similarities to an Aqua Hot system. The most common reason for air in the fuel system for a Hurricane in a Beaver Coach is loose clamps on the fuel filter for the Hurricane. That filter is usually located on the wall behind the Hurricane and it is accessible from under the coach.
If you can not find any fuel line problems, you probably need to install a fuel return line to let any air travel back to the fuel tank instead of going through the Hurricane burner. Installing a fuel return line is fairly easy. You just take the hose that exits the bleeder valve, install a small orifice (about 1/64 inch) in the hose and add enough hose to connect it to your generator fuel return line. Then you open the bleeder valve and leave it open all the time. The small orifice insures that the Hurricane still has an adequate fuel supply, but it vents an air back to the fuel tank to prevent it from going through the burner.
The return line should stop the backfire problem, but it will not increase the heat output. The Hurricane should keep your coach comfortable at temperatures well below 0 Celsius. So be sure that your summer/winter valves are not set wrong or are partially open.
Gerald