Almost thirty years ago I scavenged an oil fired hot water tank from the local dump.
Back then no one wanted oil fired hot water because it was not cost effective.
So my father, grandfather and me made this little fire box that fit where the the oil burner had been.
Grandfather discussing the great war as a kid, the depression and how they made things and made do, father discussing how much the depression and the second war rationing sucked, and me doing the actual work of making the firebox…
This rig has lasted no word of a lie almost 30 years service having water at the family cottage…
The video shows a man with some junk rigged with stove pipe and copper coils and burning a lot of wood to heat water.
This is a waste of time and effort.
Years before I built this water heating system out of the oil fired tank I was enlightened by the oldest man I knew at the time…
Big Aldo, a man who lived threw two wars in Italy and had a lot of ideas on a lot of things.
He showed me his rig at the cottage up the lake from ours.
He used gas fired water tanks because the fire box was smaller and he figured it would burn less wood that way.
He also used a raw water filled cast iron radiator in his cottage as a heat dump if there was too much fire and supplementary heat for his dacha if things got too warm in the tank ( this is an important part to refer back too ).
Aldo suggested two fires a day were all any campers might need and claimed this could be done with squaw wood ( scraps that fall off the trees you collect around an encampment when you do your daily walking routine or morning constitutional ).
I listened to non of this advice…
I built a mighty fire box that could hold about as much wood as the video shows…
Within 20 minutes of lighting the fire I had boiling hot water of about 30 gallons.
Within an hour I had a further 150 gallons of steaming hot water in the water tower near the heat as the gravity based system over heats and withing an hour and half all the PVC pipe was softening and starting to leak around the dacha.
So in conclusion:
If you want to heat water off grid use an old gas fired hot water tank ( with a short stack I also must add because you do not need much draft )
Use small pieces of scraps you collect around you and not firewood or kindling.
Re-fire late in the afternoon with another small fire and this will supply you with showers and hot water for dishes all day and all night and have something rigged up as a thermal heat dump to blow off excessive heat like a radiator up hill gravity fed if you over stock the fire.
Its very very easy to overstock the fire…