... often times the supply and return are in the wrong places, and folks don't understand that often times there is some internal plumbing. If you pull heat from the top and return to the bottom you are doing nothing to promote a balanced tank of water
So where is the ideal location to place the outlet pipe? It would seem the very bottom of the water jacket doesn't make any more sense than the very top. The return line should also extend into the water jacket by at least 2/3rds the total length of the water jacket, shouldn't it? Would you also recommend the return line be higher than the outlet line or lower?
I'm going to be building my own boiler in a few months and these are questions I have yet to resolve, so any advice you can give would be appreciated!
No definitely not out of the lowest point.... Most are about 12-14" from the bottom and the returns are maybe 6-8" from the top, and yes you can extend that forward into water jacket for even better circulation. If your supply is at the top, as I've said it does nothing to promote water circulation, and them factor in the if you have any kinda boiler over and you lose some water, your pump is gonna be destroyed as well. Most pumps we use, use water for lubrication and fail when they run dry.
When you get a good balanced tank of water everything works better and the stove is better protected, just keep your probe sensor away from the return where it emptied into the stove