Step 10: You're all wet
-a large pot, 5 gallon bucket, or a water tank (do you want it open topped to keep it clean, or closed) dark in color to keep things from growing.
DO NOT HEAT WATER IN AN UNVENTED TANK IT WILL EXPLODE.
-copper pipe or tubing (a coil will get even better heat out put, but must always slope upward from the combustion chamber)
-JB weld water weld (special epoxy mix made to seal and even cure underwater, and safe for use in drinking/cooking repairs per the web site)
-drill bit the same size as the pipe.
-mark the bucket where you want the pipe to go in and out. ( a horizontal run through the bottom of the tank would do the most good for heat transfer)
-drill the holes
-push the pipe through and seal the holes with the JBweld
-fill and check for leaks.