.....I'll be boondocking 99.9% of the time so I'll only have electricity to heat water when the generator runs. ......
I'm trying to figure out the best way to turn the diesel heater on/off as domestic hot water needs to be heated. I could turn on the diesel heater and it will circulate coolant continuously and turn on/off as needed, but that would probably burn a fair bit of battery.
Maybe the best solution would be to just use the generator when I need hot water and forget about the cost and hassle of getting the water heater to turn on the diesel heater when hot water is needed. I only use the bus twice or three times a year anyhow and it might be cheaper to burn diesel in the generator.
... we can let the Pro- Heat and the water heater's heat exchanger make the hot water, but it takes 2 hours and a lot of cycles of the Pro-Heat to accompish ...
... by the way, which water heater do you have? do you have a link, model? you too Sean what do you have?
... I have a Webasto system and plumbed where I can bypass all my coach heaters if I want no heat and send all the btu's to the water heater heat exchanger. I do this with a manual 3 way valve (one in, two outs).
If I'm boondocking I usually let the genny heat the electric element in the water heater while I charge the batts. It seems to (though I've not verified) heat the water faster than the webasto.