Your Surburban furnace can be looked at anywhere that is a Surburban repair facility.I have a V nose Snowmobile trailer also,26 ft. You have at least a small Battery to provide 12v to the saftey breakaway for the (Brakes)! This is not large enough for the Furnace&blower! The short run time is related to Low voltage to the blower?Thcooking stove eitherrowing a high temp shutdown. Your tow truck has to have the pin hooked up for the Remote batt,just because the trailer lights work does not supply voltage to the remote Batt. Ps,mine does not have a cooking stove either!
I hope you ride a (POLARIS)