Water Heater Idea

Introduction: Water Heater Idea

This is an idea for a water heater. It is a work in progress. We are posting it as an instructable for a class project.  If this design becomes very functional when the kinks have been worked out, it may be used in a student’s home he is building. We are open to any additional instructions that may help get this water heater to a functional and realistic state.

Step 1: Materials

To replicate this model start by collecting your materials

Which include:

Tank- some kind of pot
Heating ducts
Cob- mud and straw mixture
Stove Pellets

Step 2: Get Your Hands Dirty

Set one heating duct on both sides of the pot
Mold the cob all around the pot and ducts to hold them in place
Mold the cob under the heating ducts and pots
Do not fill in the heating ducts
Build a kind of bowl shaped structure out of the cob large and strong enough to set the pot and ducts on
This area will be where your pellets go and the heat comes from
Put the pot/duct structure on top of the bowl shaped bottom
smooth the sides with more cob so it is all one structure

Step 3: Imagine

For all the parts that we didn’t include in this model you will have to imagine to get the total gist of how this water heater works and why it’s beneficial. 

This water heater is supposed to function as a more sustainable option to what’s sold. It also empowers the owner to build it suited to their own needs, even with a minimum budget. The fuel for the fire, the use of gravity, and the placement of the ducts all enhance this model and its benefits.

 In order for the heater to fulfill its destiny there are a few more things you would have to do. First, the water heater would either its self be located at roof level or just the water catchment system. If just the catchment is located on the roof, then the water would then run through some sort of piping, through the hole in the lid of the heater, and into the tank, from there out the bottom of the tank through piping to various locations in the house. There are pros and cons to both positions. One option to find a happy median was to put the heater at roof level, install a pellet feeder and ignition, and put their controls centrally located somewhere in the house.

The water heater model we built did not have a sufficient tank for daily home use but a water heater could be built with any sized tank in the same fashion this was built. You would also want to experiment with and document the amount of pellets, time it takes to heat the water, the prefered temperature range, and the time the water will stay in that temperature range.

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    7 years ago on Step 3

    For years I was a leader for a Boy Scouts of America troop. We had a "camp water heater" . The heater (first iteration) consisted of a rubberized storage bin (about 10 gallons or 40 liters) with a low hole and high hole drilled in one end. The holes were fitted with hose connections and radiator hose was connected. Into the radiator hoses was inserted each end of a section of flexible copper pipe shaped in a spring type coil. A small fire (we used charcoal briquets stacked in the coil) supplied the heat. Natural induction drew, relatively, cooler water from bottom of tank it was heated in coil and returned to tank through upper hole.

    The second iteration solved a few minor issues that came out during our first camping trip. The tank became too flexible to move when the water reached about 100 F so we built a plywood box that was 4 inches larger in all dimensions than the tank, lined it with 2 inch foam insulation and drilled holes for radiator hoses and attached handles. We also added a spigot to the end opposite the other connections and built a stand so a 5 gallon bucket would fit under spigot.

    So long as the hot (upper connection) side of the run did not lose heat faster than cool (lower connection) side induction will work no matter how high you place the tank because it is relative heat variation that matters even if relative difference from top to bottom is minuscule.

    Maybe this will give you some ideas maybe not good luck.

    As an aside the water heater made another appearance in camping when some of the boys "aged out" of boy scouts (all male) and moved on to the Boy Scouts of America Venture Scouting (co-ed). They made the supply lines longer so they could surround the tank with a frame and tarps while the coil and fire was outside. They took this winter camping and had a nice sauna in which to warm up. I thought the tarps they bought were unnecessarily large for a sauna for 4 boys until my son smiled and said, "They won't be too big if the girls bring their swimsuits next time."


    9 years ago on Introduction

    You say you will burn pellets Why not design and make a cheap and affordable pellet mill.That would be a fantastic project. Best of luck with this one


    12 years ago on Introduction

    Try looking up 'Rocket stove' for some ideas on getting the most out of a small fire.


    12 years ago on Introduction

    I would use something like a radiator in between the holding tank and the stove. When the stove is fired it would heat the water within the radiator which would in turn be pushed into the the holding tank. Also I would add some sort of chute and metal catch bin to get rid of the waste from the pellet fuel.