How to Make a Water Heater

Measure and cut one hole centrally in each end of the tank or drum, so that the 150 mm pipe fits through snugly. Push the pipe right through the tank, and solder, weld or braise in place, ensuring that the joints are water-tight, so that it is flush with one end. This will be the bottom of the water heater. The pipe is the chimney.

Measure and cut a hole in the top of the water heater, into which the J-shaped pipe fits snugly, and solder, braise or weld the longer leg into it. This is the overflow/expansion/pressure release pipe, without which the heater will either not function at all, as you will not be able to pipe water into it, or will turn your water heater into a bomb that will explode with devastating consequences.

Cut one or two holes into the bottom of the tank and insert, solder, weld or braze them into place to act as inlet and outlet, or use one pipe to perform both functions, or just cut a hole in the top and pour water into the tank. You will, nevertheless, require an outlet at the bottom, onto which you should fit a tap (faucet), if you do not want the water to run out as fast as you pour it in.

Cut a rectangular hole into the bottom of the topless 300 mm high cylinder, through which you will feed fuel for your fire and via which you will remove the ash.

If you intend using this water heater indoors, cut a second, round hole in the back, opposite the rectangular hole. Affix a length of pipe of that same diameter as the chimney, to this hole.

Push the pipe through a hole in the wall so that the other end of the pipe is outside the building so that, as long as the firebox door is closed, the fire draws air from outside and not from inside.

To make a door for the firebox, use the rectangular piece of steel you cut from the front and apply two hinges and a latch and catch as illustrated:

Position the tank on top of the topless cylinder and weld or braise in place.

Fill the tank with water, make a fire in the bottom and let the water heat up.

Your water heater should resemble something like this when finished.