I like the space heater idea. Our typical camper use doesn't call for space heating during solar hours, but doing something like that would address a concern I have with my water heater idea. I feel I should have a thermostat control just in case the water is already at design temp. If the scenario is that the thermostat says no more heat allowed, then the diversion current has nowhere to go. The CC manual makes statements about making sure the diversion load can accept all diverted amps otherwise...something? That part requires more research. I think it dumps it back into the battery, which at this point doesn't need any more charging. Or maybe makes magic blue smoke??
