Building my own OWB - the lowdown

[trialanderror]

Nice job so far... Do yourself a favor and grind the rusty steel before you weld it!

i did...i ground the slag from torching and beveled all the edges.
they're not serious leaks...

they're super tiny ones...
like, pump 25psi in it, and wait for 5 minutes, there'd be 7-8 tiny bubbles about the size of a pin head each....

i did discover the best weld is a silent weld...pops and snaps are a bad sign. the only things you should hear is music and the buzz/hum of the welder....

 

[cleanburn]

Its coming together

I agree with Blazin, make sure you are grinding that stuff before welding

 

[trialanderror]

my gas getter dumped the transmission the other day (the case cracked and split down the side!?!?)

so, garage is tied up for a while. doing some indoor plumbing.

on the note of HX's. is there a quality difference? anyone bought the cheap ones that are seamless and have had no problems?

http://www.ctwoodfurnace.com/parts_water_to_air.htm

shooting for those.
200k for the house, 100k for my mom's orchid plant thingy room... she wants that all fancy and warmer then the house so...yeah, need 2....

 

[trialanderror]

got it installed.

having dual forced draft in the front and back is crazy!!! when it calls for heat...it HEATS.

i'm impressed.

 

[John D]

Now that you've had it up and running a week,how is it doing so far?

 

[trialanderror]

Now that you've had it up and running a week,how is it doing so far?

not sure. i don't live there it's like a hour drive north. My awesome gas getter (ford aspire) puked. transmission case split...another project scheduled for next weekend

I'm on call this weekend. Next weekend i'll be able to get up there. Talked to my dad on the phone. he said he loves it. he was putting nearly 2 wheelbarrows of wood in each stove a day. (2 houses, each one has a cookstove and a furnace, so figure twice a day loading, 5 to 6 loads for decent heat) now he loads it 2 barrows a day, and can acutally melt ice on the shop floor

The waterjacket, firebox dimensions are simliar to heatmor's 100 and 200 css models. i went totally overkill and installed 200k btu units in each house. reason for this was i could acheive the same BTU/hr with 130-140*F water instead 180-195. . I figured have it and not need it then to need it and not have it.

It was worth it. nearly all the money went into the underground plumbing, about 200ft of logstor. $12/ft. . $100 worth of steel into the boiler.

we did some wheelin' and dealin' and hooked up with a 300 and 500 gal propane tank. Next one is going to be a monster. As we're putting up a 40x60 with 22ft cieling this summer. So i'd say be safe and double the 40x60 sq footage because of the cieling height. ,Gonna heat the floor, so might have to make a bigger boiler. But i think this one can keep up with it. I installed a 200gallon storage tank in each houses garage, dad experimented with bypass shutoffs and it helps alot with overnight single digits and below zero's. it'll pull heat from the water instead of burning the wood during the night. quite a bit more of reserverd thermal storage. I'm honestly thinking about going with even more water in the future... When it calls for heat, it runs longer, instead of wasting heat/smoke when smoldering. As that smoke does burn and create heat.... that steelking came weith firebrick on the bottom, and man, i was there last weekend, and i opened that door, and it was seriously 20" deep of red hot coals, side to side 24" worth , 28" back.....and the blower's push air from udner them, as there's ash grates. I may have to plumb the return water on the top of the water jacket, when them blowers kick on, once in a while you'll hear a pop/crack of water boiling....

anyways. parents are satisified. clean cheap heat. it's what they wanted. someday all the 80acres and 3 houses are gonigto be handed to me, so it was future preparation you could say.

 

[boyland]

built my own also

I built my own following DEB design IV boiler.

I had some minor leaks go to menards by boiler sealer it will take care of any of those minor leaks. On the water jacket exterior, you can use plumbing expoxy if you have anything to worry about. I found most of mine just went away.

You do not have to be a perfect welder to do this project. But the Time it takes is quite extensive. If I was to do it again I probably would get everything ready and have a welding shop with a high voltage welder do the job.

Also whatever size you think you need I would add 30% more. When I was building this thing I thought man this thing is big then once I started using it I wise I had made it 2 times the size.

 

[trialanderror]

i've done alot of stick welding, and i did this with a wirefeed. just a plainjain millermatic 220volt... i think it tops out a 260amp? i used .035 wire and c10.



most of my leaks i peened with a punch. And the ones that still bubbled with 20psi, they never leaked with water in it and zero PSI....makes me wonder what happens if you do the same with a brandname boiler?

anyways, wirewelding, there should be no popping/snapping. Supposed to be dead quiet with the exception of the frequency tone. everytime it pops/snaps it's a dirty weld. Way different then stick. also cranking the amps and making a deep weld is the best. ANyways, only got 2 full weeks into it. Turned out nice.

there's absolutely NO way i could of done this without a chain hoist. i had to flip and turn and roll it nearly 1/2 million times to get all my welding done.....

 

[trialanderror]

well, just to summarize.

Boiler: Steel King 4300B 40 Gallon; working pressure 30PSI, 145CFM draft blower, firebrick. 6" chimney. Rated for 485,000 BTU/Hr.
Price: free.

originally designed to be setup down in the basement, as it's not insulated in any shape at all. Originally had; 4 1.5", 2 1", 1 1/2" fittings.

The work:

Added a water jacket to the front of the firebox, the back, around 12" of the chimney coming out the back, and around the entire bottom. Also added a 2nd 145CFM draft fan to the front. Only exposed area of firebox is on the far bottom, where the ash door is. Cant' say it's part of the firebox though, since it's luke warm to the touch at any time. From some rough crazy math, increased water capacity to about 85-95 gallon, give or take. Added 4 more 1 1/2 fittings in various places. 2 more 1/2" fittings

Material Used
bought some 6" 1/4" wall pipe for the chimney to extend the backside 12". Added some 2.25" flat stock around the front to bring that out about 2.25". The steel to use for water jacket addition was laying around everywhere, tripping over it, moving it 10 times every year, figure i'd use it for something useful. 1/2 of it was a truck box someone scabbed together.

Bought a 44# roll of .035 wire. $38
Burned a K tank of oxygen. $30
Burned a K tank of C10 - not sure what it costs, it's been around for years

All cutting was done on a 10# tank of propane (i know, i'm a cheap b!tch, i only use acetylene when gas welding or cutting anything over 2", or making rubber boomers...condoms are the safest, I'm not kidding!! there's no static electricity)

Insulation, 24" on the top center peak, down to 18" on the top edges, peaked roof. 18" insulated on the sides, back and bottom. 12" on the front. Plain jain insulation batting. R of 4.3-4.7 per inch.
Price: Free.

Skirting, some sheet metal i had laying around. Used some clear silicone to make it water tight
Price: free.
Plumbing, 1" ID Logstor. 2 zones, one 85Ft, other 76Ft. 1" copper in the house. Somehow dad ended up with like 80 ft of 1" copper rwith some aluminum fins on it, so, any straight runs in the garage or basement i used that to dissipate the heat better. Few years ago some flea-market shopping and he bought 18 1.25" brass ball valves, and my buddy 'found' 36 reducer bushings at his work in the inventory room....

Logstor was $12/ft. The guy said give him a call and when he drives to holland to make a delivery he'll meet me at a truck stop near holland, which was like a 20 min drive for me. Said give him $10 and call it even. I couldn't argue it.

For the controllers thermocouple, i had to do some shopping, but i found a comp nut and some bushings, and with a bunch of reducers, the probe goes in the smallest reducer, working it's way up to a 1.5" tee, and the water basically elbows in the tee, fully encasing the probe. Couldn't of worked out better.

Pumps are GrundFos UP26-64F with 1.25" throats. Rated for 33GPM with 1' of head. I'm about 8Ft. specs sheet says 22.5GPM with 7' head. They were taken from a hydronic job over in easttown, bearings were bad, i took them apart and some lube work, they work like a charm. Even if i get 1 year out of them, better then flipping $380 a piece.

Heat exchangers, 22x22x3.5" 1" sweats. If water is 180*F at 22GPM it's rated for 200k btu/hr. 130*F water and 22GPM will dissipate about 130K btu/hr.
Price: $286 each. One in each house.

Heat Exchanger for the garage: GMC diesel radiator. 4.5' x 38" 2.5" inlet and outlet. No fan. It sits down in the pit under the staircase. Just the high amounts of heat radiating from it pulls down the cool air and pushes up hot air.
Price: free.

Can't really calculate my time. I did about 1 week of constant work. But then i had to work 60 hr weeks and occasionally a weekend, so, it got spanned out over a month. Maybe 2 weeks of 8hr days.... nearly 1/2 of the work was while on vacation, so, i got paid to build most of it.

Am i missing anything besides pics? those will come soon.

 

[trialanderror]

sorry guys, been in jail for a while. it's ridicules what happened. ended up pleading guility for a felony with 7411 treatment..... pocessiion of 2 1/2 tables of vicodin....

i'm on probation for a while.


anyways. the boiler is nice. it's set at 200F. 180gallon system. heats a 220k BTU inside the house. and also heats a *massive* mack truck radiator in the garage (2nd zone, radiator is about 4ft by 3ft, so large it doesn't need a fan to heat the garage )


it burns roughly 2 fireboxes of wood everynight. the zone in the garage has ball valves that i shut down almost close when i'm not doing anything in there (soon to be modified later) and the house is a 5/2 program thermostat. 62F at night, then shoots to 72F during the day.

i burn trash wood, punky pine, water logged poplar, leaves, yard waste, if it burns and turns to ashes, i cram it in there.

picture me putting all my might into the door trying to get it juuuuuust closed enough to get the latch to start so i can bind it down air tight...lol...

for the draft i used two peices of steel with a solenoid. all relayed with 24v, so my dwyer controller won't fry from contact loads.

the blower heats the coals so intense it jumps 3-4 degrees within a minute....

it's always going on/off, if it's ideling, and no one is pulling heat, it's on for ~1 minute at the most. off for about 12-15.....

 

[trialanderror]

finally re-configured the controller to shutdown at a high temp and turn on at a low temp

cut down the wood consumption quite a bit.

the family and i are quite impressed. Unfortnaly i never did build one from scratch. I recently acquired a 1000Gallon steel tank that's 7/16" thick. Not sure if i want to make that the water jacket, or the fire box.....i have crazy thoughts about it.....


I'm quite impressed with it. Burns about a medium wheel barrow full in 10 hrs. Softwood, not sure about hardwood, saving that for january time. IM just happy we're not going to blow $6500 this winter for propane for both houses & garages....no, that figure is not a typo.....

 

[cleanburn]

If I had that tank you are talking about, I would make that the waterjacket for sure and build a firebox in it or just use it as what it is. A water tank

The 7/16" thick is pretty thick for heat transfer and its huge, so it wouldn't make a good firebox in my opinion.

Jail huh? :censored:

Best of luck to you

 

[trialanderror]

fortunately for a few days....

good thing the state focuses their resources and manpower on dangerous, corrupt, and unstable people like me.... And then they shut down facilities because of insufficient funds, letting robbers, vandalists, gang members and etc walk free, their sentencing cut short....

yeah, i figured it was overkill for a firebox.... I have a 500 gal if i trim will fit inside of it. Not sure. Gonna see how well this one performs for a full winter. Appreciate your help man you know what i'm talking about...

i poured a slab, put skirting around it, and added a stainless steel chimney, galvanized blew out within a month or so. Also got my home made hydronic-dryer going, and soon a hands dryer for in the bathroom

Next summer, hot tub.......

I'll grab some pics when i find time. been busy building a 8 way wedge'd splitter for all these BTU's i'm gonna be needing....well, that's been my focus, aside of skidding, splitting, and stacking, 60hr weeks, and my other 209834570298357 projects i got going on...

next priority is a bigger building...ha, that needs to be heated!

 

[cleanburn]

I wish I would have put radiant tubing under my garage approach :censored: it would have saved me a lot of shoveling.

If you do any more slab stuff like that I would recommend it, might as well, you just have to heat the slab above freezing to keep it nice