Outdoor Wood Furnace Info

Outdoor Furnaces - Manufacturers with NON EPA-Certified Models Only => Home Made => Topic started by: WoodMOJoe on March 24, 2013, 01:10:47 PM

Title: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on March 24, 2013, 01:10:47 PM
After consultation with my financial advisor (aka wife), a neighbor (master welder and fabricator) and many hours of studying the forums here, I have decided to attempt an OWB build.

It's great to be able to see the great work that so many of you have done here, get ideas, and maybe avoid some pitfalls along the way.

I have attached a preliminary drawing .pdf to this post, please check it out.  I'm sure a lot of the dimensions will change somewhat, but it will give you a pretty good idea of where I am headed.

Outer water jacket tank is a propane tank, 41" O.D. x 79" long, 360 gallon capacity.  One of the half-sphere ends will be cut off, flat plate will be welded to that end to accomodate the 20x20 door opening.

The firebox will be 30" round piece of propane tank (with a section cut out full length on the bottom and flat plate welded in) x approximately 48" deep.

Water capacity should be somewhere around 160 gallons when completed.

Flue will be 6" Sch40 steel pipe, it will extend about 12" into the firebox and exit horizontally into the water jacket, then I will go vertically with more 6" after it exits the water jacket.  The horizontal piece will extend outside beyond the flue and have a cap, to access the horizontal tube for cleaning.

Door will be a pre-manufactured 20" x 20" unit with draft induction fan built in.

No ash pan, no grate.

1" bungs will be provided on the back end of water jacket, from top to bottom:  2 for return, 2 for drywell (aquastat) or thermometer, 2 for supply.  Returns will be extended up high to be near the front of the tank, supply will be drawn from down low and near the back of the tank.  A 1 1/2" or 2" outlet will be provided on the bottom for tank drainage.

A 2" threaded bung already exists in the middle of the top of the water jacket, for fill point, venting, water level float....?

This whole assembly will set up off the slab on a metal framework, and eventually all will be enclosed/insulated in a metal framed and sheathed structure.

All comments/thoughts/suggestions are welcomed!   :)



Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: skorpyd on March 25, 2013, 05:35:33 AM
Looks like a very good plan.   Mine is pretty much the same.  The only difference I see in my build is that I welded a 90 degree turn in the horizontal flue inside the fire box so the opening was pointing down, then ran the top of the horizontal flue 3" down from the top of the inside of the firebox.  I haven't got mine going yet so I don't know if it would be better or worse.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on March 25, 2013, 06:35:52 AM
Thanks skorpyd.  I studied your thread and got a lot of ideas for my build.   :thumbup:

I also am considering going with a 90 turndown on the horizontal tube in the firebox, but wondering about creosote buildup at that point.  I guess, worst case, most of it could be cleared from the opening at the outside end of the tube, and the downward facing section could be accessed from the firebox.

Also planning on copying you on getting the outer structure framed and firing it up without putting the insulation/skin on, to check out operation before it's all sealed in.

How did you get your tanks safe to cut into (explosion hazard)?
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on March 25, 2013, 07:58:13 AM
Here is a revised drawing, firebox is now fully round.  Will post some pics of the tanks next chance I get.

Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on April 02, 2013, 05:16:52 PM
Here are some pics of the propane tanks we cut the water jacket and firebox out of.  We ran car exhaust through the tanks for about 30 minutes before cutting, have done many using that method, and still alive to tell about it.   ;)  You are on your own if you try it though...

http://img.photobucket.com/albums/v646/barkeywayne/WoodFurnacefireboxandwaterjackettank03-26-13_zpsa2c2a295.jpg (http://img.photobucket.com/albums/v646/barkeywayne/WoodFurnacefireboxandwaterjackettank03-26-13_zpsa2c2a295.jpg)

http://img.photobucket.com/albums/v646/barkeywayne/WoodFurnacefireboxandwaterjackettank203-26-13_zpsa02b2138.jpg (http://img.photobucket.com/albums/v646/barkeywayne/WoodFurnacefireboxandwaterjackettank203-26-13_zpsa02b2138.jpg)

http://img.photobucket.com/albums/v646/barkeywayne/WoodFurnace30inchfireboxtank03-26-13_zpsad5cbcd6.jpg (http://img.photobucket.com/albums/v646/barkeywayne/WoodFurnace30inchfireboxtank03-26-13_zpsad5cbcd6.jpg)

http://img.photobucket.com/albums/v646/barkeywayne/WoodFurnace41inchwaterjackettank03-26-13_zps1f34b180.jpg (http://img.photobucket.com/albums/v646/barkeywayne/WoodFurnace41inchwaterjackettank03-26-13_zps1f34b180.jpg)
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on May 09, 2013, 09:27:42 AM
And just like that, it is done!

Here are some "naked" pics.  Will install and run it for a while like this before it is enclosed.

[attachment deleted by admin for space issues]
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: Scott7m on August 18, 2013, 03:35:20 PM
Looks good!  :thumbup:
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: andyhowardcity on August 18, 2013, 05:22:00 PM
Very cool!  Bring on the cold weather.  I really like the stack design.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on August 19, 2013, 06:03:53 AM
Looks good!  :thumbup:

Thanks Scott, you gave me some great ideas for this build and I incorporated several of them.

And I bet you may recognize the door also.   ;)
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on August 19, 2013, 06:08:29 AM
Very cool!  Bring on the cold weather.  I really like the stack design.

Thanks AHC, it was a very cool project and I look forward to doing another soon.  We are going to build one for the guy that helped me with mine.  It's gonna have a shaker grate, ash pan and be capable of coal burning.

Can't honestly say I am looking forward to cold weather but I can't wait to install and get the new system up.  We have had the coolest summer in my memory this year, highs in the 70s and low 80s in August...me likey!   :thumbup:
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: Scott7m on August 22, 2013, 12:11:47 AM
Yep, I recognize, you did a good job! It should do great  :thumbup:
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: Acetylene420 on September 04, 2013, 05:12:12 AM
Hello everyone. I'm new to the site. I've been doing a lot of research around here and decided to join. I've started my own build of an OWB.

I really like the design of this burner. Especially the horizontal section of exhaust. I may do something similar on mine.

The question I have is why the hot water take off is near the bottom of the water jacket rather than the top? I'm assuming the water will be constantly circulating so its not so much a question of "heat rising" bit wouldn't you still gain a little more efficiency if the hot water take off was near the top and the return was at the bottom so the return water had to circulate up and around the firebox to head back to the house?

The reason I'm asking is because most of the home built units pull from the top and return at the bottom. I'm very interested in the reasoning for your design. I'm second guessing the planned placement of my take off and return now. You seem to have a great grasp of what you want to accomplish and would greatly appreciate any info you could provide.

THANKS!!!
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: Scott7m on September 04, 2013, 05:01:37 PM
You want to have a balanced tank of water for boiler protection, cool temps in the bottom can cause condensation to form in firebox and cause rust out issues fast.  So by top return your encouraging the water to be mixed more than normal therefore creating a more balanced temp throughout the boiler. 

There is no efficiency to gain to speak of, but this simple thing has solved a lot of boiler issues.  Look around, brands like heatmaster and natures comfort all return water to the top for a reason
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: Acetylene420 on September 05, 2013, 04:53:44 AM
Thanks for the info. I'm going to pull off the bottom and return at the top.

I appreciate the explanation.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: dukilee76 on October 18, 2013, 02:02:02 AM
nice pic jan
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on November 05, 2013, 02:02:04 PM
Some progress to report, hx is now installed in plenum.

My plenum is about 19 3/4 x 19 1/2 inside dimensions so I went with a 19 x 20.  Cut a 3 1/2"+ slot and made a couple of shelf angles out of some 26 ga. Galvalume, these were attached to the inside of the plenum walls to carry the coil.  Also, made a couple of angles to enclose the exposed 1" or so of coil that projected out the front face of the plenum.

Backhoe should be available within the next couple of weeks, then I can get serious on this project.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on November 19, 2013, 02:05:30 PM
Here's some pics of my underground install.  It's Badger 5-wrap inside of 6" SDR35 bell-end gasketed PVC.  Top of 6" pipe is about 24" down with about 6" clean crushed limestone under it, and about a foot over the top, then about a foot of dirt over that.

I used a 3 1/2" core bit to go through the 8" concrete wall, of course I found and hit a piece of 1/2" rebar DEAD CENTER of my hole.   :bash:

A 3" Sch40 PVC pipe fits that 3 1/2" hole (with a little persuasion), then I got an adapter to go from 3" Sch40  to 6" SDR35, worked slick. 

I had to take some of the 5-wrap off to get the 2 1" pex lines through the 3" sleeve through my basement wall.  I also removed the black perf tile on the end at the furnace and curved the insulated pex lines though a couple of 6" SDR35 45 degree bends to get it out of the ground.

I pulled some 12/2 Romex though the black perf tile using the provided pull string, and I also ran an empty 3/4" conduit for a just-in-case.

[attachment deleted by admin for space issues]
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: dave_dj1 on November 19, 2013, 04:15:53 PM
Sweet! :post:
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: Fourced on November 20, 2013, 06:47:58 PM
Do you have any pics of the inside? I am curious what you did with the flue opening.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on November 20, 2013, 08:32:47 PM
Do you have any pics of the inside? I am curious what you did with the flue opening.

I had a bunch of pics of the construction process that I lost in a hard drive failure.   :bash:

The flue opening extends horizontally into the firebox about 8" off the back wall.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on November 21, 2013, 07:26:33 AM
Here's a couple of pics of my "foundation".

4" thick slabs of Carthage limestone...price = $0.   :thumbup:



[attachment deleted by admin for space issues]
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on November 21, 2013, 07:29:37 AM
And the unit when first placed on the foundation.


[attachment deleted by admin for space issues]
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: Fourced on November 21, 2013, 05:55:21 PM
I am currently looking for a solution for my boiler, if I don't cover the flue to some extent I lose a ton of heat. I made a plate that forces the smoke down and out, so far I have burned up a 1/4 plate and have done major damage to a 1/2 plate. I am trying to design a new plate for this winter. My horizontal pipe is 8", a 90 would be expensive.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on November 21, 2013, 06:31:49 PM
I am currently looking for a solution for my boiler, if I don't cover the flue to some extent I lose a ton of heat. I made a plate that forces the smoke down and out, so far I have burned up a 1/4 plate and have done major damage to a 1/2 plate. I am trying to design a new plate for this winter. My horizontal pipe is 8", a 90 would be expensive.

I remember you talking about the insert plate in your thread and wondered how it had worked out.  Please post a pic when you figure out what you are going to do and let us know how it works.

Sounds like something I will probably need to try eventually on mine...IF I ever get it going.   ;D
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: hondaracer2oo4 on November 21, 2013, 06:54:26 PM
Fourced, you could take a section of 4x8 box, weld up a cap on one end, torch out an 8 inch hole for the box to slip over the horizontal flue pipe and then weld it up so that the smoke has to reach the bottom of the stove in order to get into it to head out the flue.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on November 24, 2013, 06:25:21 AM
My outside line connections.  Return goes in high towards the front of the water jacket, supply comes out low on the rear:





[attachment deleted by admin for space issues]
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on December 01, 2013, 06:32:14 AM
Framing for the enclosure:



[attachment deleted by admin for space issues]
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: hondaracer2oo4 on December 01, 2013, 07:35:49 AM
Holy Moly! You didn't screw around with that enclosure! Looks like some sort of bomb enclosure, that thing is awesome. You must have had a lot of scrap steel laying around. I am always trying to find steel.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on December 01, 2013, 08:13:55 AM
Yeh, I have hundreds (thousands more likely) of feet of various sized steel members "in stock" around here, from constructing steel buildings.  It is all 16 ga. 4x2 cees, open channel and angles.  And again, the price tag is $0.00.   :thumbup:

The roof and north wall will extend about 4' from the front of the furnace, planning on mounting my controls on the extended north wall for easy access.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: Wood Nutt on December 01, 2013, 08:19:52 AM
No "show me" for that Missouri fellow.  Looks great.

I can't believe what is thrown away on construction sites these days.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: hondaracer2oo4 on December 01, 2013, 10:32:37 AM
Very cool. When do you plan on starting to burn?
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on December 02, 2013, 05:36:40 AM
No "show me" for that Missouri fellow.  Looks great.

I can't believe what is thrown away on construction sites these days.

Thanks Mr. Nutt.  I wouldn't have even known where to start on this furnace project without the help of the good folks on this website.   :thumbup:

Yeh, I built my own house and outbuildings, and lots of the materials were extras/demoed from construction projects.  Never could have afforded to do what I did without that stuff.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on December 02, 2013, 05:38:54 AM
Very cool. When do you plan on starting to burn?

Thanks...Hoping to be in operation by Christmas.  The old outside wood air furnace will do the job until then.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: fryedaddy on December 06, 2013, 07:33:38 AM
Your project looks nice.

My father-in-law may be building one like this.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on December 06, 2013, 02:05:24 PM
Your project looks nice.

My father-in-law may be building one like this.

Hey thanks there fryedaddy.  Good welder, strong back and weak mind is all the qualifications ya need.   ;)
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: amhst56 on December 31, 2013, 03:17:22 PM
WoodMojoe,

     Thanks for all the info. I'm thinking of doing the same thing.
I have planed everything out, but can not find a premanufactured door anywhere. Where did you get yours?

Thanks
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on December 31, 2013, 05:08:06 PM
WoodMojoe,

     Thanks for all the info. I'm thinking of doing the same thing.
I have planed everything out, but can not find a premanufactured door anywhere. Where did you get yours?

Thanks

I got mine from Earth Manufacturing in Mountain Grove, MO.  They are about 70 miles from me so I just went and picked it up.  I got their 20" x 20" model, complete with frame, fan and fan cover it was right at $400.  I bet they would ship you one if you need that.

Here is their phone number:

417-746-0043

http://earthwoodfurnace.com/ (http://earthwoodfurnace.com/)
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on January 15, 2014, 07:09:16 AM
Here is a progress pic, getting closer:

(http://img.photobucket.com/albums/v646/barkeywayne/WoodFurnace01-12-2014_zps6f61eb12.jpg) (http://smg.photobucket.com/user/barkeywayne/media/WoodFurnace01-12-2014_zps6f61eb12.jpg.html)

thanks to astro_ss_340 for helping figure out how to post pics.   :thumbup:
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: hondaracer2oo4 on January 15, 2014, 11:29:57 AM
Looks great.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: skorpyd on January 15, 2014, 04:57:33 PM
Looking real good.  It's so very similar to mine.   Even down to the five wrap inside of the 6"pvc.   It looks like you also had to take off the black exterior pipe at the fittings.

It looks like were on close to the same timeline also.  I have everything done except siding and insulation, which I'm waiting for initial fire up to be sure of no leaks.   This Saturday is to be the big day.   Hopefully yours will be soon also and we can compare notes.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: ms1780 on January 29, 2014, 01:47:49 AM
Woodmojoe I am close to you and was curious if you might know where a guy could get some tanks like you used. I live down the highway by diamond Missouri.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on January 29, 2014, 07:04:47 AM
Woodmojoe I am close to you and was curious if you might know where a guy could get some tanks like you used. I live down the highway by diamond Missouri.

You might try looking on Craigslist, or propane dealers selling off tanks that they can't rent anymore.  I lucked out, a buddy of mine had the 2 I used.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on February 16, 2014, 07:21:39 AM
Here is some "finished" pics.  The door on the back came from an old steel kitchen unit, perfect size.

Since our well water has so much lime in it I am going to fill the system with distilled water, that should happen this week.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: mlappin on February 16, 2014, 07:45:27 AM
Here is some "finished" pics.  The door on the back came from an old steel kitchen unit, perfect size.

Since our well water has so much lime in it I am going to fill the system with distilled water, that should happen this week.

You can buy one time use filters from Central boiler to fill it from your well. Not sure how well they work, but it's CB right? Must work.

I've seen a few manufacturers recommend soft water. Woodmaster dealer in town told me when I built mine to never use soft water as it will contain trace amounts of salt.

Another manufacturer recommends rain water.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on February 16, 2014, 08:19:46 AM
I had never seen those CB softener cartridges before, interesting, thanks for posting that.

Looks like they are about $150, that is just about exactly what my 180 gallons of distilled water is going to cost.  I have a 40 gallon plastic barrel, going to pour the 5 gal containers of dist water into it and use a little electric transfer pump to get it into my boiler.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: Wood Nutt on February 16, 2014, 09:05:32 PM
Softened water still has a lot of suspended solids in it even after softening.  Its an ion exchange if I remember correctly and the softening process only substitutes the softening material (salt?) with the lime that probably makes it hard.

If you are close enough to a bigger town (Joplin?) that has a public water system, many post their treated water samples on-line and the municipal stuff is treated enough that it is good for boiler fill water.  I hauled my water from town in a 225 gallon agriculture tank, chained it to the front of my dump bed trailer (so it would not slide back), pulled the trailer next to the stove and lifted the hoist and put the tank about 8 feet in the air.  I then let gravity flow the water into the stove.  Since you are in the construction business, you probably know someone with a dump bed trailer I assume.  The city water would be a lot less than distilled!

Good luck and BTW, the stove looks great.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: skorpyd on February 17, 2014, 03:25:30 AM
Looking real good,  glad to hear you are about ready to fire it up.

My well water is pretty bad with a lot of iron and lime in it.   I used it just so I could get it going without much hassle.

I plan on draining it in the off season and collecting rain water to fill for next year.

I hope you get it going soon so that you can use the end of this season to figure out if any adjustments are needed.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: hondaracer2oo4 on February 17, 2014, 07:25:12 AM
For anyone out there that is curious how a water softener works it is like this. Water is passed through a resin bed which is located in the fiberglass tank of the water softener unit. As water passes through this resin bed the minerals in the water including up to 10 ppm iron are attracted to the resin and attach themselves to the resin beads. Depending on how 'hard' your water is at some point your resin bed will become saturated with minerals and won't be able to collect any more. At this time you would perform a 'backwash' on the system. This is when the salt comes into play. The salt acts as a brine solution that rinses the mineral deposits off of the resin bed. This brine solution is then either dumped into your septic or more preferably into a drywell. After the resin bed has been backwashed it will now be clean of mineral deposits and be able to start softening the water once again. Resin beds do have to be replaced every so often depending on how bad your water is. The average I think is every 10 years the bed will need to be replaced. So the salt isn't actually pumped into the house, but trace amounts could be left on the resin bed after a backwash. I don't think that it would stick around for very long at all. The resin bed goes through a long rinse cycle after the brine solution.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: mlappin on February 17, 2014, 11:49:07 PM
I had never seen those CB softener cartridges before, interesting, thanks for posting that.

Looks like they are about $150, that is just about exactly what my 180 gallons of distilled water is going to cost.  I have a 40 gallon plastic barrel, going to pour the 5 gal containers of dist water into it and use a little electric transfer pump to get it into my boiler.

Try this instead, 50 bucks for the unit with two cartridges.

http://www.woodboilersolutions.com/pro/cart/product.cfm?memberid=1926&detailid=1851&startrow=1&maxrows=100&productid=119 (http://www.woodboilersolutions.com/pro/cart/product.cfm?memberid=1926&detailid=1851&startrow=1&maxrows=100&productid=119)

The company that handles the softener unit also highly recommends soft water if it's available.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on February 18, 2014, 07:29:02 PM
Thanks to all for the kudos and info.

Now considering getting a small (50-100 gpd) 4 or 5-stage reverse osmosis system to fill the boiler tank with.  There are a few RO systems like this in the $175-$250 range.  I have a yard hydrant about 25 feet from the boiler, could plumb the RO system in temporarily and top the tank off.  Then could use it for topoffs and lend it to my buddy when he fills his system up.

We have a few days in the 50s or 60s now, and the old homemade FHA rig has kept us warm for the last few years, so no rush... ;)
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: Sprinter on February 21, 2014, 07:40:33 AM
Inline filters, 1/4"-1/2" sizes, just have to fit some hose fittings. RO is about a 10:1 ratio. Takes 10 gal to make one RO gallon. Just as long as your aware. Condition of well water will dictate the exact ratio. Those Zero water pitchers actually do pretty good, but no matter how you filter its gonna take just a little extra time...
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on February 22, 2014, 01:45:44 PM
...RO is about a 10:1 ratio. Takes 10 gal to make one RO gallon...

I did not know that.  Does that mean there is a port for the "waste" water? 

Like if I hook the inlet of the RO filtering system to my hose bib, and the output to my boiler fill pipe and run approximately 200 gallons of treated water into my water jacket...there will be 2000 gallons of "waste" water that will be discharged out of another port on the RO system?

The system I gotis 5 stages and is rated at 100 gal per day.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: Wood Nutt on February 23, 2014, 10:53:42 AM
Yes, there is a waste port on the RO systems.  The system I have hooked up in my house for drinking water and to the ice maker claims about 4-5 gallons wasted per gallon of RO water produced.

The way it was explained to me, the RO membrane filters the stuff out and the large amount of waste is used to flush the membrane.

Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on February 23, 2014, 01:51:20 PM
Thanks for that info Wood Nutt, did not know that.   :thumbup:

I should have my RO system next week, and will be filling my boiler soon after.  Hoping to just run the new system enough to work the kinks out this spring, then have it 100% ready to go next fall. 

The old homemade FHA rig has paid for itself about 4 times over just this winter...and it's on it's 4th year!
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: Rstory on February 27, 2014, 06:03:40 AM
If you had it to do over. Would you have grates & ash door
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: mlappin on February 27, 2014, 06:24:27 AM
Thanks to all for the kudos and info.

Now considering getting a small (50-100 gpd) 4 or 5-stage reverse osmosis system to fill the boiler tank with.  There are a few RO systems like this in the $175-$250 range.  I have a yard hydrant about 25 feet from the boiler, could plumb the RO system in temporarily and top the tank off.  Then could use it for topoffs and lend it to my buddy when he fills his system up.

We have a few days in the 50s or 60s now, and the old homemade FHA rig has kept us warm for the last few years, so no rush... ;)

Not sure which manufacturer I seen it from but they said NOT to use water from a reverse osmosis system to fill the boiler. Not sure why.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on February 27, 2014, 07:07:11 AM
If you had it to do over. Would you have grates & ash door

Since I haven't even fired mine up yet that is hard to answer, but at the time I built mine I didn't want to deal with the extra work required to produce ash door and grate.

There are a lot of good-performing factory-built units that don't have them, that was my thought.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on February 27, 2014, 07:12:31 AM
Thanks to all for the kudos and info.

Now considering getting a small (50-100 gpd) 4 or 5-stage reverse osmosis system to fill the boiler tank with.  There are a few RO systems like this in the $175-$250 range.  I have a yard hydrant about 25 feet from the boiler, could plumb the RO system in temporarily and top the tank off.  Then could use it for topoffs and lend it to my buddy when he fills his system up.

We have a few days in the 50s or 60s now, and the old homemade FHA rig has kept us warm for the last few years, so no rush... ;)

Not sure which manufacturer I seen it from but they said NOT to use water from a reverse osmosis system to fill the boiler. Not sure why.

I have never seen anything like that but it is possible.  There is a lot of info on the 'net that details the advantages of using RO water in boilers, but most of it is specific to pressurized systems.

Our water here is exceptionally hard, we have 2 limestone quarries within 3 miles of our house.  Lots of limestone outcroppings on our 100 acre, it is everywhere.  Just hoping to get some more mileage out of our exchangers, hot water heaters die a fairly quick death around here on untreated water.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: Wood Nutt on March 01, 2014, 08:04:08 PM
The RO systems advise using all plastic line and fittings.  Apparently the system is so efficient at cleaning up the water, noting is in it and it starts bringing metals back into solution.  They don't advise using copper for RO but I did it originally.  I have now changed it out to Pex and looked at the copper and it was eroding it, but it took years to accomplish (10+).  That may be why there was one manufacturer not recommending it, maybe it will attack your copper, brass, and or steel in the system???
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: mlappin on March 01, 2014, 09:16:11 PM
The RO systems advise using all plastic line and fittings.  Apparently the system is so efficient at cleaning up the water, noting is in it and it starts bringing metals back into solution.  They don't advise using copper for RO but I did it originally.  I have now changed it out to Pex and looked at the copper and it was eroding it, but it took years to accomplish (10+).  That may be why there was one manufacturer not recommending it, maybe it will attack your copper, brass, and or steel in the system???

Wonder if in "normal" water the minerals or trace metals act as the sacrificial material much like an anode rod in a water heater?
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: Wood Nutt on March 02, 2014, 09:03:29 AM
The place that sold me the RO system called water in its pure form, the ultimate solvent since it will eventually dissolve many things, metals, rocks, etc. :o
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on March 07, 2014, 07:45:16 AM
(http://img.photobucket.com/albums/v646/barkeywayne/WoodFurnaceROWaterSystem03-05-2014_zps36a6d012.jpg)

Been filling the tank for about a day and a half now, by my calcs the RO system is producing about 45 gal per day.  I think my water jacket capacity is about 180 gals, gonna run the last 20 or 30 gallons in straight from the hose (through the sediment filter only).  My theory is that will give me a tankful of filtered water with very low lime and some (desirable?) trace element content.   ;)  Of course I will have boiler treatment in it also.

Should be full by Sunday if I don't have to shut it down Saturday night (mid-20 degree lows are forecast).  Monday and Tuesday are to top out around 70 so I will just fire up the pump one of those days, bleed the system and check for leaks.

As soon as the temps are going to be down to 40s or 50s for highs for a couple days next week I will light the fuse.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: Sprinter on March 08, 2014, 04:52:12 PM
RO water or h2O is completely nuetral , it will not attack or erode anything. The benefit of using pure water is to eliminate ionized minerals that will attack anything metal. In closed systems after a cycle and up to temp the water becomes dead as we call it. Anytime fresh air is reintroduced into the system , a bunch of new oxidizers are now present to start oxidizing AKA rusting eroding of metals. This is why those brass micro bubble air separators do so good at eliminating this and extending equipment life.  With open systems there is always some level of corrosion going on, and boiler water treatments are designed to neutralize as much as possible. They take away the excess positive and negative charged molecules , making them neutral
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on March 12, 2014, 05:18:42 PM
Well, after 6 days and 20 hours +/- I finally filled my water jacket to the top of the fill neck.  I only run about 55 psi on my house water system so that kinda slowed things down, this RO filtering system is good up to 85 psi (rated at 100 gpd at 85 psi).  About 180 gals of filtered RO water plus a half gallon of boiler treatment in the system now.

No fire yet but I opened my valves, filled the lines and started the pump.  It was squealing a little so I cracked open one of the pump flanges a fuzz and bled the air out.  That quieted it down, can't even hardly hear it running now on high speed (Grundfos 15-58).  Circulated water for about 30 minutes with no apparent leaks.   :thumbup:  Running more RO water in right now to top off the tank again.

Building a 90 degree turndown that will slip over the horizontal flue pipe that extends onto the fire box.  That should help retain the heat a little better and not allow the fan to blow as much heat right out the flue (I hope).

Will probably light 'er up this weekend, March 17 will be a year to the day that we cut the propane tanks and started the ball rolling on this caper.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on March 21, 2014, 04:50:22 PM
Have been heating the house and DHW for right at a week now and all systems are go.  Hasn't really been super cold but I have no doubt this rig will keep up with anything Mother Nature throws our way.  A couple of minor hiccups but I am learning to run the system better as I go.

Thank you to all the great folks on this site that have contributed to helping me build and install my setup...couldn't have done it without you!    :thumbup:
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: hondaracer2oo4 on March 21, 2014, 06:09:29 PM
 :post:
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: skorpyd on March 27, 2014, 02:59:15 PM
Congrats,

My fire has not went out since mid Jan, when I first fired it up.   You are going to love it.   I have a couple things to do in the off season after learning some things about how to use it.   

I'm also planning to build a wood shed around it to hide it and make it look more like just a shed.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on March 27, 2014, 05:18:12 PM
Congrats,

My fire has not went out since mid Jan, when I first fired it up.   You are going to love it.   I have a couple things to do in the off season after learning some things about how to use it.   

I'm also planning to build a wood shed around it to hide it and make it look more like just a shed.

Hey thanks, going on 2 weeks here, no major issues yet.

How did your "OWB making too much charcoal" deal turn out?  Is it cured?  I am noticing some of the same tendencies with mine.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: skorpyd on March 28, 2014, 02:38:47 AM
Joe,

I still think it might help to have a stronger cfm fan on mine, but It seemed to be partly a learning curve issue as well.

I do most of my burning in the firebox closer to the front where the fan is.  I also put that air diverter on the existing ducts that were built into my door so I was directing air more down from the door opening.   So doing that and also using an old hoe to rake the larger coals up to the front when I load it has produced much better burns.

This off season I may try to put a larger fan on mine though.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on March 29, 2014, 01:26:12 PM
Some good ideas there, thanks.

I have the exact same model fan as yours but mine has a gravity-operated flapper in the tube that goes into the firebox...rather than the solenoid-controlled setup you have,

Did you ever find a higher cfm fan to replace yours with that wouldn't require much modification where it attaches to the door?
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: skorpyd on March 29, 2014, 04:40:28 PM
I was doing some research when first having the problems burning and had a Dayton 130cfm unit that was about the same size but now I can't find my notes.

I think it was model 1TVD2, from a seller on ebay.   But now I have to go back and compare specs.   I guess I should figure it out and order one.
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on December 21, 2014, 07:54:52 AM
Installed a temp gauge off of a bbq grille to my door.  Lets me know what is happening inside before I open the door.

(http://img.photobucket.com/albums/v646/barkeywayne/WoodFurnaceDoorTempGauge12-17-2014_zpsec08c6d8.jpg) (http://smg.photobucket.com/user/barkeywayne/media/WoodFurnaceDoorTempGauge12-17-2014_zpsec08c6d8.jpg.html)
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on December 21, 2014, 07:57:18 AM
Added a little lean-to wood shed to the side, can park a truck bed under it if desired.

(http://img.photobucket.com/albums/v646/barkeywayne/WoodFurnaceShed12-17-2014_zps02f73fd7.jpg) (http://smg.photobucket.com/user/barkeywayne/media/WoodFurnaceShed12-17-2014_zps02f73fd7.jpg.html)
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: tinfoilhat2020 on January 13, 2015, 05:46:59 AM
very nice, starting tghe same project here as well. 250 gallon inside a 500 gallon!
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on December 10, 2017, 05:47:09 AM
Fired off the beast for the season yesterday, this will be the 4th winter providing heat with this setup.

Didn't really keep track of the labor required to build everything but I was south of $2K cash outlay, so it was probably paid for after year 2.

Cleared a 1/4 mile of fence row a couple of weeks ago and rebuilt our steep and rut-prone driveway, that gave me about 5 years of oak and hickory that is now cut up and laying in the pasture curing out.

Thanks again to all who helped me out on this caper, couldn't have done it without you.   :thumbup:




Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on November 27, 2018, 04:44:00 PM
And we are off again, heating season number 5 for this homebuilt has begun!

If I make it through this winter my cost of ownership, all-in (boiler, exchangers, underground pipe, fittings, etc.) will be about $350/year.

I'm guessing it has paid for itself at least twice over with what it has saved in propane bills.

That doesn't include the value of many man-hours of labor between me and my buddy building the boiler of course but that was time well spent.

And once again, thank you to all helped me make this thing happen, some still posting here and some not...much appreciated!   :thumbup:
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: BoilerHouse on December 01, 2018, 07:56:16 AM
Great to hear of another success story.  I will be into my 10th season this year.  My build cost was roughly $6,000 all in.  I buy logs each year for $1,000 and I used to go through 4 tanks of oil per heating season @ close to $1,000 per fill up.  So about a 2 year payback, although I always have extra expenses over and above the wood.  This year was more extreme than usual.  I bought a new pump to have as a spare, bought new cast iron grates which, at $400, were surprisingly expensive, and finally bought a real cant hook, in lieu of the home made one I have been using for years.  Still, I will save over $2000 in fuel costs this year. 
Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on December 02, 2018, 07:12:11 AM
Wow, congrats on the 10 years...and holy woodburner, I just searched and found some pics of what you built.

My boiler is a very simple and crude toy compared to that...nicely done sir.

We don't have the cold weather as you in Ont. so it's not a huge money savings for us but I just like waving at the propane truck when they pass us by and not depending on someone else to heat our place.

You are making some pretty good money with your setup.   :thumbup:

We have 100 acres of hardwood forest (oak, hickory, locust, hedge, ash, black walnut) here in the Ozarks, I can't even cut a good percentage of the dead trees.

And my neighbors just selectively logged (several varieties of oak, black walnut) 40 acres right next to me and told me to cut the tree tops if I wanted...an embarrassment of firewood wealth.

Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on April 08, 2019, 10:51:52 AM
Shut down for the season this morning, 4 1/2 months after we fired it in November.

Here's a pic of the beast, cooling down till next winter:

Title: Re: Homemade "Tank-in-Tank" OWB-Ozarks Hillbilly Edition
Post by: WoodMOJoe on January 03, 2020, 11:12:33 AM
Just to update this thread I fired up this year on December 14, 2019.

This is year 6 for the homebuilt so I think my yearly cost for the whole system (furnace/enclosure/lineset/heat exchangers/fittings and misc.) is well below $300/year now.

Great investment and thanks again to all that helped me with my build!  :thumbup: