We have a 2011 Sunseeker 3100 with the arctic pac and have never used it. The LP furnace heats the tanks, water filter and pump, and the dump station compartment. We've been in the coach overnight in 19 degrees F with a 20 mph wind and had no problem. I checked the compartments the next morning and they were over 50 degrees.
For your information, if you are camping in cold weather and don't have an electrical hookup, the furnace will use about half the power of two batteries overnight. You'll need to run the generator several hours to fully recharge the batteries. Having the batteries run down during a cold night when you aren't allowed to run the generator is not fun! You can get by just fine with a 20 amp hookup for the furnace if the refrigerator is running on LP (it uses a little 12 volt power even when on LP), you don't use an electric heater, and you don't use too many lights at once. However, if you have LED lights, you shouldn't have to worry about using lights.
Also, for information, the coach's 12 volt system normally starts the generator. If they batteries are run down and you don't have electrical hookup, you can start the chassis engine which will give enough 12 volt power to the coach's system to enable you to start the generator, then shut down the chassis engine.
Look through this forum. There's lots of information on the Sunseeker/Forester lines, their appliances and system.
By the way, if you have internet access during your campouts and run into a problem, you can often get help from forum members fairly quickly. Just post your problem with something like: Need Help about XXXX - On The Road.
PS If the furnace hasn't been run much, run it for at least 15 minutes with the door and some windows open before you leave home. New furnaces burn off some residue and can set off your smoke alarm.