This morning I finished putting the furnace back together and tested it. It ran perfectly after I got the air out of the propane lines, and re-attached the exhaust/intake vent cap outside. Without the cap, the furnace would choke itself out with its own exhaust.
The Travco came with two batteries, one up front for the engine and coach, the other in the back for the generator. A previous owner had installed a 2 gauge wire from the engine battery to a battery switch under the sink, with another 2 gauge wire coming from the generator battery to the same switch. I added a third 1/0 wire from the four inverter batteries, that I tied together with the inverter under the bed, to the switch. I wired the engine/coach battery as Main, the inverter batteries as #1, and the generator battery as #2. At the moment I don't have any battery isolators so, I have them all connected together so that my solar panel and charge controller can keep them charged (they also get charged when the engine or generator run). Also, since I am connected to the grid while at home, I use a battery charger to keep them topped up (like a charger/converter would... the charger that came with the Travco died). Since I use the Travco as an office and play the stereo and use the lights and soon the furnace, the batteries would soon die without a charger.
Battery Switch under the sink for the three battery sets.
Under the bed: engine fluids in crate, 35 gallon water tank (from a Winnebago, has level sensors, but not connected), leveling blocks in bags, bottle jack, inverter batteries tied in parallel, 1500 watt inverter, electric water heater, 2 gallon water pressure expansion tank.
One of my next projects will be to connect the 1500W modified-sine wave inverter to the 120v electrical system. Currently I must run an extension cord to where I need the power (if running the inverter for power), so I want to design, build, and put in an automatic transfer switch for the inverter to connect it without the generator or utility power connected.
6 hours ago