Building OWB with Propane tanks

Hello everyone,

New to the site and looking to build an OWB. Just bought a 1795 Colonial in New Hampshire and need to find a cheaper way to heat it than the current forced hot air oil burner. The attic is fully insulated and the first floor above the basement is also. I am not sure about the walls yet as we have not moved in and I have not been able to take a look in the walls. Anyway, I am a mechanical person and enjoy building things myself. I was interested in using possibly a 150 gallon old propane tank for the firebox and a 250 gallon old propane tank for the water jacket. It looks as though other people are using the 250 gallon tank for the firebox since it is larger. I think I will have to go this route myself. That means I will probably need a piece of a 500 gallon tank for the water jacket. I plan to make the unit pretty simply with the firebox mounted inside the water jacket with a piece of plate steel that covers on the front of both. Planned on using a 6 inch pipe 1/4" for the flue mounted halfway into the firebox. I plan to put a forced draft fan on the bottom of the ash door. Any suggestions people have I would greatly appreciate. I have not been able to find any propane tanks yet after calling all of the local propane companies and them telling me they refurb their tanks and that they wouldnt tell me who the refurb company is! Also what thickness metal and what type should I use for the front plate and making of the doors? Thanks alot everyone!

What do you guys think about a 30 inch by 70 inch tank from some kind of pressurized use for the burn chamber? It appears to be 1/4 walls and was used to hold something under pressure but not really sure what, it says american brake on it. Also what do you guys think about a 12 gauge 500 gallon diesel fuel skid tank as the water jacket? I know 1/8 inch seems a little thin.

I think unless you spend the money and do the system completely with consumer produced components you wont be happy and have nothing but problems.Just my 2c on that.For heating I like an indoor stove myself and you cant beat how simple it is to install and maintain.

Sounds like you want to build something just a little bit like this: http://www.arboristsite.com/firewood-heating-wood-burning-equipment/143845.htm

Oh, and for the record - I couldn't be happier! :check: Did I mention that I like how simple and easy it is to maintain? AND that the fire is outside of the living space?

I looked at a DIY boiler myself just like you are. After I started adding up prices, and put some value to my time, I discovered I could buy one for about the same money. I am now the owner of a Timberwolf.

Ranch,

Yours looks very similar to what I had in mind. I am up in New england but any ideas on where to get the propane tanks? It looks like from this chart BEST OUTDOOR WOOD FURNACE! that some of the manufactures fireboxes are only 1/8 thick. What do you guys think about using the 500 Gallon oil skid tank like this http://www.northerntool.com/shop/tools/product_47575_47575?cm_mmc=Google-pla-_-Fuel%20Transfer%20+%20Lubrication-_-Auxiliary&%20Transfer&%20+%20Skid%20Tanks-_-109582&ci_sku=109582&ci_gpa=pla&ci_kw={keyword} As the water jacket? It says that it is 10 gauge and I found one locally for $100. I know that it is just thicker than 1/8th but how long do you think that it would stand up for? Also H Ranch how much wood do you go through a season and what are you heating? The way I have been adding up metal with $100 for water jacket and $250 for firebox plus a 4x4 sheet of cold rolled steel for the front for around $100 and other metal to build the door, chimney stack etc we are looking at just about $1000. Then I need a blower, Hot water heater thermostat, Pex pipe(100 feet made myself will cost $250), Heat Exchanger , water pump and fittings. That should be around $750. So The way I see it is $1750 with my labor for a boiler and the closest price I can find is $4500 not including Pex and Heat exchanger.

Check big local scrapyards for propane tanks - I picked mine out of a mountain of them for $260 and they cut the 500 gallon in half for me. Steel may have been a bit cheaper then. The 500 gallon is at least 3/8" thick and the smaller tank is 1/4" (I wish it was the other way.) Don't cheap out on the PEX - it can't be too well insulated. $1750 is a pretty aggressive target. I could have done mine for a little less, but not sure I would be able to knock $650 off (see my cost breakdown in my link above.) I probably saved $8000 by doing everything myself so that's not a bad wage.

I'm heating a 2500 square foot house with 30' cathedral ceilings and I'm using 8-9 cord for the winter. That was probably 50% hickory and 50% poplar/cottonwood/basswood.

The propane tanks work great. Mine is on it's 5th year. While shopping for your water tank. Keep in mind that they have 2 different 500 gal tanks. The "normal" 500 you see all over and also what I was told, a 500 gal tank that is called a "short fat 5". These are obviously shorter and bigger diam than normal. Mine is built with a short fat 5 and a ? gallon burn chamber. 24" diam X 40" long.
I really LIKE mine but I'll admit I don't LOVE it.
Burn chamber to small.
not enough surface area "burn chamber to water"
the part of burn chamber that sticks out is wasted heat.
View attachment 196130

Build it this way instead
View attachment 196131

Aim,

Yes the drawing is what I was thinking for a design. Do you guys think that a 10 gauge 500 gallon diesel fuel skid tank would not be thick enough walls?

I dont know a thing about the boilers (although I am reading about them) but I have cut several propane tanks and in my experience there are several diffrent "Grades" of tank out there. I have a 1000 gallon in th elot right now that is over 3/8 thick. Most of the smaller ones are a soild 1/4 that I have cut into. It is a shame you are not closer I could get you any size you want up to 1000 gallon for 50.00 each. I have a good hookup.

Hey rio

How far are you from evansville indiana??

About 3.5 hr last time I made the trip