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[Fourced]

It is balanced so it closes, I must have it far enough away from the fire, I only get a light glaze of creosote on the butterfly.

[chaikwa]

I see you are pulling the water OUT of the boiler at the bottom of the tank and returning it to the top. A lot of boilers, both home made and commercially made do the same thing, while others I have seen do exactly the opposite and pull the water out of the boiler at the top and return it to the bottom. Is there a reason for either? I would think pulling from the top would provide the warmest water while returning it to the top would cool the water that's already been heated, making the whole thing less efficient.

Anyone care to give me some insight on this?

[Bondo]

I see you are pulling the water OUT of the boiler at the bottom of the tank and returning it to the top. A lot of boilers, both home made and commercially made do the same thing, while others I have seen do exactly the opposite and pull the water out of the boiler at the top and return it to the bottom. Is there a reason for either? I would think pulling from the top would provide the warmest water while returning it to the top would cool the water that's already been heated, making the whole thing less efficient.

Anyone care to give me some insight on this?

Ayuh,...   I question the sense in that too,....

I built mine to send the hottest water at the top, to the house, 'n return at the bottom....

[Scott7m]

I see you are pulling the water OUT of the boiler at the bottom of the tank and returning it to the top. A lot of boilers, both home made and commercially made do the same thing, while others I have seen do exactly the opposite and pull the water out of the boiler at the top and return it to the bottom. Is there a reason for either? I would think pulling from the top would provide the warmest water while returning it to the top would cool the water that's already been heated, making the whole thing less efficient.

Anyone care to give me some insight on this?

It's better to have a balanced tank of water, most everyone pulls from the bottom.  Returning the cold water to the top helps to balance the tank.  It's also aids in circulation of heat in the water inside the tank, it helps eliminate "cold spots" in the tank, all are thinks you don't want. 

If your only worried about having the top portion of water hot, then why do we need the water at the bottom?  I think in thinking of it in that matter would be like saying I have a 100 gallon boiler, but only use 60 of the gallons

I have helped a couple home made guys who were pulling from the top fix circulation issues by switching that around, some of those problems included boiling in the front part of the stove and 140 in the back. 

Also, if your boiler was set at 170 and that's what the water was at the top, you sure would t want cooler water surrounding the firebox at the bottom, that would cause moisture in the wood to possibly gather on the cooler firebox walls vs going out the stack

[skorpyd]

I'm going to take my supply/hot off of the lower outlets.  From what I've seen it does get better circulation, and I was also thinking that the lower outlet would supply more water pressure for the pump.

[Scott7m]

I'm going to take my supply/hot off of the lower outlets.  From what I've seen it does get better circulation, and I was also thinking that the lower outlet would supply more water pressure for the pump.

Also if you have a boil over, if your supply is on top your gonna lose a pump or pumps much faster than if they were lower, if you run those pumps dry they won't last long

[WoodMOJoe]

Fourced, is that an oxygen cylinder that you used for your horizontal exhaust tube?

How is this beast running for you?

[Fourced]

Fourced, is that an oxygen cylinder that you used for your horizontal exhaust tube?

How is this beast running for you?

Yes it is, the boiler has kept us warn all winter and we have not used an ounce of propane.

It burns very clean, it only smokes when it idles.

[WoodMOJoe]

That's great, glad to hear it worked well for you. 

I am considering going together with my neighbor to build a couple of OWBs, and at least one of them will be very similar to yours.  I can "weld" but he is a master welder/fabricator.

Anything you can think of that you would have changed if you had a chance to build yours again?

[Fourced]

I love the horizontal pipe through the water, I will be changing my door. I did make an insert that goes in my horizontal pipe to help limit the flow of heat out of the stack.

[WoodMOJoe]

I love the horizontal pipe through the water, I will be changing my door. I did make an insert that goes in my horizontal pipe to help limit the flow of heat out of the stack.

Could you take a pic, or describe your horizontal pipe insert?

I am going to buy a pre-manufactured door/frame/fan assembly for mine, considering the cost and time involved to make my own I think this will be a better deal for me.

[Fourced]

If you look on page one there are pics of the firebox and the pipe. I made a plug that goes inside the horizontal pipe to limit heat flow. the firebox/pipe is holding up well because the water protects it, the insert was 1/4 steel and has been destroyed in 2 months, the 1/4 plate looks like a tin can now. I have drawings made up to make one out of 3/8 and maybe 1/2 to try to get it to hold up to the heat.

It sounds like a rocket when the flame burns the smoke down the horizontal pipe. I will try to get a picture of it when it is burning, it was doing it tonight when I was loading. It looks and sounds cool.

[chaikwa]

It's better to have a balanced tank of water, most everyone pulls from the bottom.  Returning the cold water to the top helps to balance the tank.  It's also aids in circulation of heat in the water inside the tank, it helps eliminate "cold spots" in the tank, all are thinks you don't want. 

If your only worried about having the top portion of water hot, then why do we need the water at the bottom?  I think in thinking of it in that matter would be like saying I have a 100 gallon boiler, but only use 60 of the gallons

I have helped a couple home made guys who were pulling from the top fix circulation issues by switching that around, some of those problems included boiling in the front part of the stove and 140 in the back. 

Also, if your boiler was set at 170 and that's what the water was at the top, you sure would t want cooler water surrounding the firebox at the bottom, that would cause moisture in the wood to possibly gather on the cooler firebox walls vs going out the stack

That's a good explanation. Thank you!

Keeping all that in mind, where is the best location to install the aquastat? And what are the advantages and/or disadvantages of a dry well versus a wet style aquastat? Maybe there's only one kind available now, I'm remembering my short 'career' as an oil burner tech in the early 80's!

I'm still on the fence regarding buying or building a unit. Being a welder/fabricator by trade, I'm sure I could put one together. Whether or not it would operate with any degree of success is what's holding me back. Firebox size in relation to waterjacket size is another point of question for me. All I can do is try and copy a unit from a manufacturer that's given me a quote on a specific unit that he says will work for my application.

I'd like to do grates with air under fire as well, but a lot of people have told me that the grates, no matter how heavily built, will just deteriorate over time and not to waste my energy building them.

I thought I had an 'ace in the hole' so to speak. I found a guy locally that built quite a few boilers for friends and family. He has been successful I guess, but in talking to him, he told me of some problems he had early on with them. He pulled his water off the bottom and returned it to the top but couldn't get more than 150 degree water at the house. In checking his water jacket with an infrared temp finder, he found a vast difference in water temp from the top of his boiler to the bottom, so much so that the water was boiling at the top and 150 degrees at the bottom. So he reversed his lines and started pulling the water from the top and it solved his problem. THEN he showed me pics... His firebox was half as long as the waterjacket and the firebox was within 3" from the top of the waterjacket as well. He had to build a little 'tower' on top of the water jacket and he fills it to the top of that tower. This makes the waterjacket FULL all the time and expansion of evaporation takes place in that little tower. To me, what he has done is NOT a solution. He has to add water about once a week to keep the waterjacket full and the firebox completely submerged.

I want to do this right if I'm going to do it, and I only want to do it ONCE. Any suggestions or advice anyone can throw my way will make me eternally grateful to you!