Thanks to you both for your prompt and detailed responses. From what I read, my situation will be more like wrinkledpants' than kcshoots'. I did not know about SMB's D5 option, but, combined with the factory engine heater, it sounds like what I'm looking for. Thanks also to David Elmore (
David Elmore home page) for his idea on a hot water return line to get hot water to the sink/shower without running any excess down the drain.
I still have a couple more questions if you have time to answer them:
With the H88 option and a heat exchanger to bring in heat from the engine, how does the system know when to pump the glycol to heat the coach if you are not turning on the D5? Does the Rixen system just take care of it for me?
My biggest concern is keeping the water system from freezing when it is -10 and I am not using the van for a few days. We often go out for a few days in winter and then park for a day or two, then go back out. I do not want to have to empty the water lines each time I stop for a couple days. My design keeps the entire fresh water system in the left-rear of the van allowing for all water components to be inside the coach. There will be nothing in the walls or floor. But, I still need to keep things from freezing. Can I keep the coach at about 40 degrees or so using the D5/Rixen system? For this purpose, diesel fuel would be preferable, but the 110v system could be used.
And one more thing: Both of you are planning to use the induction cooktop and microwave. What do you consider "plenty of battery power and a big enough inverter?" I will also have A/C needs for summer in Arizona.
Thank you again for your valuable ideas.