Looking to buy a wood gasification boiler, PLEASE, HELP!

[wsurfer49]

Greetings to all and I am thrilled to find this site.

I live in Northern Arizona at 7,200 ft and actually have winter. At least the 2 feet of white stuff outside should indicate that winter is here. I have been heating my 1500 sq ft home with a wood stove and occasionally light up the fireplace for backup. I have been renovating and have added several rooms and in the process have installed pex tubing and had planned to put a coil inside my wood stove and do storage etc. Have come to the conclusion that: 1; I want the wood burning appliance outside the living quarters 2; an efficient wood gasification boiler would be much better than the OWB'S 3; I am gone a week at a time and the Greenwood just does not look so good considering the 2 hour time to reheat the refractory 4; I would probably build my own water storage and so the GARN is probably too expensive for me. Any plans out there for water storage? A workshop is on the drawing board for next year too and I am undecided as to locating the furnace in the shop or between the shop and the house. Don't want to give up too much workspace and definitely wouldn't have room to store the firewood in the shop.

I have read several of the different threads and have discovered the mixing valve concept and sounds logical to me. One of the furnaces I was considering has a steel model and a stainless model for $2,000 more. The others vary and of course price is a consideration but there is no substitute for quality so I usually try to spend a bit more than I want to.

Any and all advice is welcome. I am not totally decided against the Greenwood but some of the others sound like they could be up to full burn a lot quicker and the house is going to be pretty cool to start off. Maybe, depending on the storage capacity, I guess. So much to consider and I would like to get as much value for the money as possible.

This is a great site and I look forward to hearing from you all. Rob

 

[Nofossil]

Welcome to the forum and to the boiler room., RobnAridzona. I have a thread going right now with live data from an EKO 25. This evening, it reached useful heat output in just over half an hour from lighting a match, and was at full output in about 45 minutes. Some folks are putting these in outbuildings - not a bad approach in my never-so-humble opinion.

Lots of information here - spend some time browsing the threads.

 

[atlarge54]

Your home isn't currently set up for a boiler, correct? When you say "often gone for a week" an alarm goes off in my brain about freezing risk. At 7500' altitude is a pressurized system required? You've come to the right place for help, lots of experienced wood burners here. How's the solar situation where you live? Some solar might reduce the risk of freeze ups. Check out nofossils setup, his has to be a showcase of most heat gained per pound of wood burned.

 

[wsurfer49]

I will be checking back on all the relevant threads as there is definitely a wealth of info here.

I have a fair amount of passive solar from the new rooms and the house plumbing has not frozen in 6 years and I have been gone for as long as 5 weeks with no heat other than the solar. I will definitely have to have a closed system from the boiler to the house and that will have to have antifreeze, with enough water storage the house may actually be pretty well protected while I am gone. I don't think the altitude will open or closed but the position of the boiler relative to the house will as i am on a fair slope.

Appreciate the quick responses, thanks y'all. Rob

 

[sdrobertson]

I'm in the final stages of planning on my system. I'm thinking a 32 by 24 pole barn with a 8 by 24 foot "boiler room" on one end of it. I'm thinking 8 by 8 for the room with a gasifier (not my OWB) in it and a 16 by 8 foot "wood storage" room that will sealable for the summer so I can run ductwork and a big fan on top and a raised floor with air slots to pull air through the room to attempt to dry the wood further. In the wood storage room I'm thinking a 2900 gallon tank made out of insulated blocks underground like a septic tank (poured core) that will be 7 by 7 and 8ft deep (inside size) with a concrete top. With the insulated blocks and 2 inches of blue board insulation and a liner I think it will be sufficient. Any ideas?

 

[wsurfer49]

The barn and storage idea sound great. I don't have too much trouble drying my wood here in Arizona though I will need to get it under cover. The 2 feet of snow we just had makes it a bit of a pain to get at all that stacked oak that I cut last summer. Will also have to try to get a little farther ahead.

The buried tank intrigues me. I just wonder how much heat loss you will end up with. You get pretty cold up there and the frost probably goes down quite a way so insulation will be the key.

I am thinking of maybe a 10x12 foot shed that will house the boiler and several weeks to a months worth of wood. I already have too many sheds though and the building inspector will be out when the shop is built so the extra shed could be a problem. Need to get the shop built then will tackle the furnace. Still would be nice to have it in the shop so will give that some more serious thought too.

Rob

 

[sdrobertson]

I'm also wondering on the tank. I believe the blocks are about r30 and made for basement walls. I'm hoping someone else may have an idea how this would work. I though of a regular septic tank but the size would not leave alot of stratification in the tank and then I still would have to insulate it somehow. I want it underground as then I can still use the area for storage above it and I wont have a problem with the strength of the walls as the ground will help with the integrity of the tank. I have also thought of putting it outside of the building and building a small roof but I don't really want to have the look on the outside of the building as I am located in a village and I want it clean.

 

[Eric Johnson]

I like the idea of an underground tank. I think you could dig a pit, line it with plastic, put the tank in and foam the living daylights out of it.

What I'm wondering is if you could get away with pressurizing a suitable plastic or steel tank that was buried. Would the foam surrounding it provide enough support to allow an otherwise non-pressurizeable (new word) tank to hold more than 30 psi? If so, that would be a cheap way to get a large amount of pressurized, virtually invisible storage.

 

[wsurfer49]

Thanks for all the ideas, got me going and some of the problems are beginning to seem pretty resolvable. One concern I do have about the refractory is that when I come back after being gone a week how gently do I need to fire the furnace and for how long. The Greenway startup recommends 3 small fires and then build a fire, a several hour process. I know it probably would not be prudent to kick it up to 2000 degrees immediately. What are your opinions and experiences with your furnaces?

Rob

 

[Eric Johnson]

I don't know about the Greenway, but that sounds to me like the break-in routine, not the regular cold startup procedure. But I could be wrong.

With a Euro-style gasifier (EKO, Tarm, Econoburn, etc.) cold startups are simply a matter of starting a fire in the primary combustion chamber and getting it going good before closing the bypass damper and initiating gasification. On mine, it's about a 10 or 15-minute process, usually punctuated by a trip back into the house for a cup of coffee.

 

[Nofossil]

I don't know about the Greenway, but that sounds to me like the break-in routine, not the regular cold startup procedure. But I could be wrong.

With a Euro-style gasifier (EKO, Tarm, Econoburn, etc.) cold startups are simply a matter of starting a fire in the primary combustion chamber and getting it going good before closing the bypass damper and initiating gasification. On mine, it's about a 10 or 15-minute process, usually punctuated by a trip back into the house for a cup of coffee.

As Eric likes to remind me, his is bigger than mine. There's an advantage to being small, though. Where he takes 10-15 minutes, I'm done in 6.

 

[Eric Johnson]

I see you knocked a minute off your time, nofossil. As I recall, it used to be 7 minutes.

In real life, nofossil is an engineer and I am a journalist. So when I say "10-15" minutes, it's an attempt to avoid actually measuring anything. Another way to interpret it would be "not very long at all." Nofossil, on the other hand, seems to have everything measured, recorded and analyzed. BTW, I just cold started my boiler and it's closer to ten minutes than 15. I think.

 

[wsurfer49]

Thanks Guys, I just went and brewed a cup of coffee but I have not started a fire.

By cold start you mean that the furnace has not run for days, even a week. I will be gone that long regularly so I will have cold starts twice a month. I think what the Greenway startup literature said was that was the procedure to follow at the first startup and at the beginning of each season.
IIf you don't have to do that type of firestarting ritual after several days of a week off then that is what I want.

I also emailed Fred Seton and he said that the Setons don't require that either.

Am beginning to lean a little more toward maybe putting my own furnace together. I think $700 is a lot of money but since I have very little background it might end upbeing money well spent. I paid over $100 for several set of plans b4 I built my backhoe and isaved me beaucoup headaches. Got a ways to go yet though, shop up first and then contemplate projects.

Rob

 

[Eric Johnson]

A cold start to me means that there are no coals to start the fire with.

 

[wsurfer49]

When your furnace has been off for 5 or more days you still just run it right up to operating temp?

 

[Eric Johnson]

I haven't had the chance to do that, but I don't see why not.