Gassification System General Questions

[Smroux]

Hi everyone,

So I have seen this touched on through various threads on here but I was hoping to get a more direct answer. 

I recently moved from CA to central NH and where we live is affectionately called the Gilmanton Triangle due to how hard the area tends to get hit with snow. This will be my first winter here, so lord knows I'm trying to figure out the best way to stay toasty. 

The house I bought has all the piping from the outside to the house where there used to be an OWB. Unfortunately, these are off the table for us now due to new regulations, unless we were to buy a used one that had been grandfathered in. Due to the logistics of that and not knowing what we would be getting we have decided on a gassifier as these meet the legal requirements. So that brings us to my questions (sorry for the blathering):

Personal preferences on best gassifier out there? 

Can someone please give me ballpark cost ideas for the install and any additional things that would be need to get this system up and running? I can find costs on a few of these gassifiers online but not all.

Do you have to have a thermal water storage tank installed with these?

Does wood have to be 100% seasoned for use? 

About our house: 2500 sq, bf is a forester/arborist so access to wood is not an issue, heating system is all baseboard heating fueled by propane currently.

I appreciate anyone's time!

Thanks,
Sarah 

[maple flats]

I was a dealer for the OWB units before gassification concepts entered the picture, but I can answer some of those questions.
If by a thermal tank you mean a large reservoir for the heating water, the answer is no, the heating units outdoors have plenty of water to store the heat. Then the hot water from the OWB in your case will just put heat into your heating system inside. It will be connected in series so you will have an either or choice on any given day. If you are asking about an insulated tank in the home for domestic hot water, while not absolutely necessary, it is far better to have one. Without one you would need to wait a very long time to get hot water to wash your hands or whatever and when the hot arrived it may well be hot enough to scald you. Most tie into a water heater tank, so the hot water coming from the OWB heats the contents of the inside water heater every time you draw hot water. Then, some people add a tempering (or mixing) valve to regulate the domestic hot water temperature, most don't use one.
I can't give you even a ball park price for 2 reasons. First I've been retired from that for 19 years, and secondly there are too many variables. Even back when I was in the business I could never give a price without a site visit. Check out 3 dealers on competitive currently approved units. Estimates were always free back when I did them.
While pipes are there from an old system, you may not want to use the old ones. Technology for the piping has changed in a big way. Years ago we had to field assemble the pipes and put foam insulation around them, then try to seal all of the seams. Then we had to pull the pipes into a corrogated tile. Most times that went OK but sometimes the seal would get damaged and there would be some heat loss. Now manufacturers of the piping insulate the pipes holding the pipes exactly the way that makes for best heating efficiency and there are no seams to fail, plus the insulation is thicker than what was used so many years ago. Today's pipe assemblies are far more efficient (less heat loss).
Study the technical specs of all of the units you get prices on and often the lowest price is not your best buy.
The wood is far better if properly seasoned but the units can and will burn less than perfect wood. Wood is never 100% dry, most is considered seasoned properly if the moisture content is under 20%. Many woods are properly dry if split and stacked where it gets good air circulation but is protected from the rain if it has aged 6 months, some do far better after 2 years. Read up on drying firewood and look at the different species in relation to drying time. Oak for example will burn after 6 months but gives far more heat after 2 years, split and stacked, there are others in that same camp.
Good luck!
Dave

[doctorb]

Welcome to the Forum:

1.  Seasoned wood is preferred by gasifier OWB's.   I have never tried to burn green wood in my gasifier, but the information seen on the FF makes me think that it's not too efficient when you do.  No, the wood doesn't have to be perfect, but the manufacturers recommend a moisture content below 20%.  As you get going, the first year may be tough in that department.  Put up 2 years worth of wood next spring and you'll be ahead of the game.

2.  Most of us have only owned one gasifier, so it will be difficult to get too many members who have significant experience with more than one brand to provide a great comparison.  The dealer makes a big difference and I would choose and OWB brand whose dealer has a good reputation with your neighbors.  There are many threads on the FF comparing the experiences of its members with regard to OWB brand.  Use the Search key near the orange Home key above.

3. As just said... no thermal water tank.  The water storage is within the stove.  Usually hundreds of gallons.

4.  As you have the underground piping, your install will include a heat exchanger to your basement propane furnace.  Some plumbing will be required to hook up the OWB to the furnace water jacket, dependent upon what the previous owner left behind.  I cannot estimate the costs, sorry.  Every house and system is different.

5.  Not mentioned....but I really like a backup generator system to keep the water circulating in the case of a prolonged power outage.  No matter how deep those pipes are buried, they still have to come out of the ground and into the OWB, where they can freeze if the circulating pumps are not working.

Best of luck.  When I started my gasifier 9 years ago this place helped me tremendously, shortening my learning curve and preventing frustration boil over.  Ask your questions and I am positive you will get straightforward answers.

[hedgerow]

Welcome to the forum.
I own a Garn it is a Gaser style boiler. Google them they are a little different as they have storage built into them. I have had it almost 10 years. I use it year around as I heat my domestic water with it. Prices on a complete system is hard figure as you may or may not be able to use the piping you have know. I have a long run on my pipes to my house and run several furnaces in my house and floor heat in my shop and I spent $30,000 on this system 10 years ago and I did all the work other than the spray foaming. I burn 10 to 15 cords or wood a year mostly locust and hedge. I haven't bought propane in 10 years. The Garn has been good it is needing the secondary burn chamber replaced. 

[DDW_OR]

NEW Central Boiler Install in Firewood and Wood Heating

End of year OWB cleaning in Firewood and Wood Heating

if i had it to do again i would get the Classic Edge Titanium

my reasons:
titanium-enhanced stainless steel = more rust resistant than my old classic edge
removable rear panel = easier cleaning and maintenance

[E Yoder]

I was a dealer for the OWB units before gassification concepts entered the picture, but I can answer some of those questions.
If by a thermal tank you mean a large reservoir for the heating water, the answer is no, the heating units outdoors have plenty of water to store the heat. Then the hot water from the OWB in your case will just put heat into your heating system inside. It will be connected in series so you will have an either or choice on any given day. If you are asking about an insulated tank in the home for domestic hot water, while not absolutely necessary, it is far better to have one. Without one you would need to wait a very long time to get hot water to wash your hands or whatever and when the hot arrived it may well be hot enough to scald you. Most tie into a water heater tank, so the hot water coming from the OWB heats the contents of the inside water heater every time you draw hot water. Then, some people add a tempering (or mixing) valve to regulate the domestic hot water temperature, most don't use one.
I can't give you even a ball park price for 2 reasons. First I've been retired from that for 19 years, and secondly there are too many variables. Even back when I was in the business I could never give a price without a site visit. Check out 3 dealers on competitive currently approved units. Estimates were always free back when I did them.
While pipes are there from an old system, you may not want to use the old ones. Technology for the piping has changed in a big way. Years ago we had to field assemble the pipes and put foam insulation around them, then try to seal all of the seams. Then we had to pull the pipes into a corrogated tile. Most times that went OK but sometimes the seal would get damaged and there would be some heat loss. Now manufacturers of the piping insulate the pipes holding the pipes exactly the way that makes for best heating efficiency and there are no seams to fail, plus the insulation is thicker than what was used so many years ago. Today's pipe assemblies are far more efficient (less heat loss).
Study the technical specs of all of the units you get prices on and often the lowest price is not your best buy.
The wood is far better if properly seasoned but the units can and will burn less than perfect wood. Wood is never 100% dry, most is considered seasoned properly if the moisture content is under 20%. Many woods are properly dry if split and stacked where it gets good air circulation but is protected from the rain if it has aged 6 months, some do far better after 2 years. Read up on drying firewood and look at the different species in relation to drying time. Oak for example will burn after 6 months but gives far more heat after 2 years, split and stacked, there are others in that same camp.
Good luck!
Dave

Good advice.
I would also mention that gasification outdoor wood boilers have come a long ways in the last several years. They're getting really nice.

[Kindlinmaker]

 Good luck, this is a complicated and confusing topic.  I’ve been researching for 3 years and will finally pull the trigger next spring with a complete home remodel. As the members have said, it is hard to find comparisons because of the equipment’s long useful life limiting individual exposures and constantly developing technology. A few general points I have learned:

• European gassers are very advanced in applied technology.  People seem to really like 1 unit available here In the U.S.  However, the available units have limited BTU output AND the manufacturers strongly recommend not using acidic wood like oak.  Like all my European woodworking tools, too complicated for my taste.
• You will get down to 2 or 3 manufacturers pretty quickly and it seems “regionality” plays a pretty big role In choice with available dealers and service. 
• There are certainly 2 sides to the water storage discussion.  Proponents are adamant about the benefits but only if it is technologically advanced storage and this comes with a serious price tag.  Opponents don’t think it is worth the investment which is a fair point but you will have to clean a non-storage boiler more often because gassers are designed to burn flat out.  Choking out a fire midburn defeats the gasser concept and will create residues which will lower efficiency and hinder proper operation.  Non-storage also requires a “dump zone” to relieve excess heat as the boiler is cooling between burn cycles.  New gassers don’t hold as much water as some or the older boilers so heat bleed is required (except Garn which has built-in storage)
• My latest estimates are in the 15 - 25K range depending on how much sweat equity I put in and how I handle storage. Garns are more expensive but they have built-in storage; owners seem to be loyal which certainly means something. A Garn just won’t fit my application or budget. 
• I will be heating about 5K ft² 
• New gassers will not operate well at all on less than well seasoned wood.  Most hard core officienados claim 12 months covered seasoning minimum with many preferring 18 - 24 months.

Send me a PM and I will be glad to share some opinions after research that I wouldn’t feel are appropriate for the forum. 

[hedgerow]

Kindlinmaker

Sounds like you have done your homework. I have a Garn we are starting the tenth year on it. It was a big investment. Now that I am ten years older getting the 10 to 15 cords of wood I burn a year is getting harder. If I was doing it today I probably would have went with a convention boiler and not spent so much money and only used it in the dead of winter and bought some propane in the warmer months. Burning wood on this scale is a life changing event. In our old house we burned wood in two wood stoves and probably only burned three cord in a long winter and burned 500 gallons of propane also. When you kick it up to 15 cord and burn year around it takes a lot of time. I have pasture that needs cleared so it is getting it done. Free wood does come with a cost.   

[Kindlinmaker]

Hedgerow

That is a serious amount of wood.  I cannot imagine cutting that much every year.  Thanks for sharing you realistic experience; it is very beneficial. I am planning to do as you recommend. I plan to only run the unit from the end of November thru end of March living in southern NY. We have a low DHW demand so I will probably tie it in for those months as I hope it won’t suck up too much additional wood. But I don’t mind heating it with the oil back-up to keep that system running somewhat. I also agree that I would prefer to continue using my wood stoves (I just love my big old Hearthstone soapstone) but the better half is tired of listening to my various fans circulating air and I have retired so I need to build the additions I’ve been promising for 20 yrs.  I just can’t get enough air moving to keep the place warm. Think my only option is a boiler tied into the oil fired baseboard hot water. I am hoping to get by on 6 - 8 cord from my current 3 - 4. Any other info or experience you are willing to share would be very welcome. 

Smroux

You can see that these systems are not a panacea nor as simple as a good old wood stove if you can get by with one.  There is nothing like walking into a home heated with a stove on a cold winter night. 

[jerry sundberg]

We have a Garn 1500, it saved us 6 cord the first year we used it. We heat home (1500 sq ft, shop another 1500 sq ft green house 10 x 32 March- May, and our domestic water) from Oct. to May. We use 12 - 15 cord of Aspen,Balsam, and Alder bushes. If we had good hard wood it would be a few cord less.

[hedgerow]

We have a Garn 1500, it saved us 6 cord the first year we used it. We heat home (1500 sq ft, shop another 1500 sq ft green house 10 x 32 March- May, and our domestic water) from Oct. to May. We use 12 - 15 cord of Aspen,Balsam, and Alder bushes. If we had good hard wood it would be a few cord less.

Jerry 
How do you like your Garn? How long have you had yours installed. 

[jerry sundberg]

We installed it in 2010. It does a good job at heating of all our buildings. We got it at a reduced price as it was a demo model that was used at home shows and was delivered right to our shop. It burns so clean you can't smell any wood smoke! I shovel out the ashes once a week about a five gallon pail full. I clean the flue pipes once a year and get a coffee can of dust. It's very easy to maintain once you get a system down. It does not operate like a OWB though, you burn it so that when your water temp is where you want it, then your firewood is totally consumed. It cannot be left outside to the weather but, has to be in a building of some sort. Ours is in my work shop and plumbed to all the buildings that we heat. I did order a separate insulation kit for it from a independent supplier as Garn at that time did not have one. Your wood should be as dry as possible (20% or less). There is never a creosote issue anywhere in the boiler as it burns it in the refractory chamber in the back. From 50* water it takes three loadings of wood to get 190* with normal winter temps 10* + maybe one to two loadings depending on wood type. Usually fire it in the evening and is good till the next day. If you go on the Garn site you'll see a video of Ernies Garn, he's had his for many years now and being as frugle as he is it has to be good ! I do all his maintenance once a year in the summer. He sold me on the Garn !

[hedgerow]

Jerry
I have the WHS-2000E model I installed it in late 2008 into 2009. I spray foamed mind now that don't want you doing that. It has been a good unit I have replaced one blower motor and getting close to needing another. My refractory chamber needs to be replaced. It has fallen apart. Dry wood is a key to them running correctly. I burn mostly locust and hedge in mine. I have mine in a small building in my pole building that houses the Garn, heat exchanger's, pumps and about a cord of wood. I have a sliding door on one side of the small building so I can park a dump trailer and unload wood into the Garn barn.  

[jerry sundberg]

Hedge
              The only things that we've had to replace are the gaskets while cleaning the boiler. They've sent me a electric isolation kit that I've installed this last week, had to disassemble the blower to drill out the mounting plate thou. Also bought the new gasket saver kit while ordering new gaskets. You mentioned replacing the blower motor, did it burn out or just the bearings? I bought a spare on e-bay for just in case. They are just a jet well pump motor 3450rpm C flange mount. Much cheaper than through Garn.

[hedgerow]

Jerry
The motor did burn out. Unit was only about three years old when the motor went out. I had a sister inlaw at the time that worked for Grainger  so I got the motor for cost like you said a lot cheaper than threw Garn. I had to cut the shaft on the old motor and put the blower wheel in a mill to get the shaft out of the wheel with out damaging it. 

[Engineer]

I heat 4300 square feet with a gasification OWB, and this winter I'll be adding 800 square feet of insulated garage to the heat load.  I installed my OWB (a HeatmasterSS G200) in January 2017, and it has been running continuously since then.  Not offline for more than 12 hours.  I use it for domestic hot water in the summer.   Prior to the G200, I had a Central Boiler non-gasser unit, and it ate 40% more wood for the same heat load.  The G200 has had a few issues, but nothing that I have needed to go back to the manufacturer for, or even to the dealer for that matter.  Many parts are available off the shelf, or can be locally fabricated.   There are good manufacturers out there and some sketchy ones too.  I would consider Heatmaster but also take a look at Polar, Portage and Main, and Heatmor (if you can find a good dealer for any of them).  I hesitate to recommend CB only because my experience with dealing with their customer service and standing behind their product, when I was first having issues with my old unit, was far less than satisfactory. 

I paid $10,000 for my unit, delivered, installed, and fired for the first time.  My dealer actually spent 24 hours at my house, camped out in his vehicle (it's a converted school bus, half RV and half workshop) and made sure that everything was working perfectly.  You rarely find this kind of service anywhere.  Unfortunately he's not a Heatmaster dealer anymore.

All of these units have a water jacket, which may (usually) contain a few hundred gallons of water.  I have heard of people adding additional thermal storage with separate tanks, but it is normally not necessary.  You do need separate storage with some of the indoor gasifiers (Tarm being a notable example) but typically not with outdoor units.

Does wood have to be 100% seasoned for use?  Yes.  I have burned "less than dry" wood in mine, and it is not to my benefit.  Primarily, you will lose some of your valuable BTUs converting the retained moisture in the wood to steam, and you will also create more creosote.  Another forum I belong to states that you should always try to have a three-year wood supply - enough for the current season, and for the next two seasons, in order to give the wood enough drying time.  Oak, especially, needs a full two years to dry after it has been cut, split and stacked. 

You should be able to install a plate-style heat exchanger and hook a new OWB right into the existing propane system.  The OWB should be able to provide domestic hot water for you during the winter, or however long you want to keep the fire lit.

[DDW_OR]

has anyone used coal in an OWB?

[E Yoder]

has anyone used coal in an OWB?

I have about 8 years ago. Lasted twice as long as oak. Gotta have a shaker grate.
Now I have a gasser (Heatmaster) and it doesn't burn coal but does burn a lot less wood.

[DDW_OR]

i was thinking of a 6 inch bed of coal
start the fire in the front and let it burn to the back.
the reload and let it burn from the back to the front