So I need to call on all the physics majors and any body with a knack for thermo and hydro dynamics. i'm trying to figure out my water system specifically the hot water because I want to have alternative heating methods. in the diagram below the very simple drawing on top is a tried and true water heater that I grew up with. hot water tank elevated above heating coils, 4 outlets to the tank hot and cold intake and out put then tank water to and from heating coil. the heating coils was 3/8" copper tubing coiled around the 6" chimney pipe. 6" pipe x pie 18+" time 10 coils a little better than 15' of coil creating thermal up lift and cycling the water WITH OUT any pumps or moving parts. only 2 cons to this. 1 too hot a fire and the water would boil in the coil... not bad just make funny sounds and then the pressure valve would vent. 2. we had hard water so every few years the coil would lime up and we would have to replace it. my dads advice was to use coolant/ oil in the coil.
this is where i need you guys the bottom part of the diagram is my skoolie blue is cold water, red is hot water, green is coolant. i'm going to have a disconnect panel going to the solar for movement and possibly for cold months, wood for winter, and LP heater if I end up some where with no room for panels and to hot for wood. now the question is where do i place the heat exchanger and the oil reservoir where i can still capitalize on the thermal moment and reduce the need for 3 pumps for the system.
the feed in to the bus is looped so when i take it to cold climates there will be more circulation to keep the pipes and tanks from freezing. i also wanted to have the heat exchanger in the under storage with the tanks but i'm not sure if that will be conducive to thermal flow.
also i thought i had an exchanger lined up that would be conducive to thermal flow but this is all i can find now.
50 Plate Wood Boiler Heat Exchanger 1" Ports Outdoor Wood Boiler Radiant Heat | eBay
let me know your thoughts