Need Advice on Larger wood boiler

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and the 3200 would be nearly $60k by the time it landed here, that's a lot of cheese!

Holy crap - I guess.

The exchange rate is a killer up here now - I thought it was bad when I got mine, but now I'm glad I got it when I did. I think it was around $1500 for freight, duty & exchange for me, almost 3 years ago. Ya, I can't see the pellet situation being any better on the rock than it is here. Can't get over how good they have it in Michigan - would really make me question burning wood.

How much would a 2000 be, landed?


18000 us plus shipping and duties or whatever
 
My direct experience with boilers that may fit your heated space needs includes:
1) A Froling FHG-L50 (170,000 btuh with 1600 gallon storage tank) heating a poorly insulated 6000 sq ft residential/visitor center, with two hot water to air plenum heat exchangers, also domestic hot water.
2) A Garn WHS 3200 (tested by me to provide 500,000 btuh continuous output for up to about 18 hours), 3200 gallon integrated storage, supplying hot water heat (with the Wood Gun) mostly through fan-coil units and domestic hot water for a 56000 sq ft residential/educational center.
3) A Wood Gun E500 (tested by me to provide 500,000 btuh continuous output), 4000 gallon external storage, supplying hot water heat (with the Garn) as indicated in (2).
4) The Garn and Wood Gun effectively share their storage capacity, resulting in 7200 gallons of available storage.
5) All boilers require well seasoned wood. Froling smaller splits, 4-6" plus some larger, 28-20" length. Garn and Wood Gun will accept smaller and larger splits, 24" length for ease of handling. Keep in mind that larger splits can take more than one spring-fall period to season.

Alll these boilers meet 100% of space heating and a very high % of domestic hot water heating needs through the coldest winter MN has to offer -- average January -10F to +5F would be the coldest month, with periods during the winter with temperatures plunging much lower, even into the -40'sF. Average wood consumption of about 100 full cords each winter, mixed hardwoods and pine.

For your needs the Froling by itself would work well to heat the house. It is both easy and a charm to operate. It requires storage, and I believe 1000 gallon is a reasonable minimum, the 1600 gallon is excellent to provide hours of heat between needed firings. With proper plumbing it will provide low temp for in-floor pex + higher temp for the water to air plenum heat exchanger.

I thing either the referenced Garn or the Wood Gun within my experience are too large for your needs. Smaller capacity models probably would work well for you. I have no information to suggest that smaller versions would operate any differently than the larger versions. Both are very good boilers. I would not recommend a Wood Gun without storage, although it is advertised to work without storage. Storage allows the Wood Gun to excel in performance by eliminating all idling and restart issues. The Garn has integrated storage.

The Garn is very easy to use, is intended for a batch burn operation, and excels in meeting needs for water temps of 140F and below, although it can meet needs for higher temp water. This is because the Garn can perform a batch burn to heat its integrated storage to a much higher temperature, then be allowed to burn out and reduce coals to ash, and to use the storage to meet heating needs until another batch burn is required. I don't get too concerned as to whether or not the Garn is a "true" gasification boiler because it is very efficient, probably qualifies as gasification, and is about as smoke free as a cordwood boiler can be. Based on quantify of ash/dead coals remaining after a batch burn (which need to be regularly removed), I don't believe the Garn is as efficient as the Wood Gun

The Wood Gun also is very easy to use and with adequate storage performs equally as well as the Garn, and would operate in a similar manner to the Garn, the exception being that the Wood Gun reduces the wood to fine ash as it burns, ash residue is collected in an ash barrel, and the Wood Gun can be operated continuously if needed. An advantage of the Wood Gun (or other gasification boiler with storage) over the Garn, if this is important, is that the Wood Gun can provide very hot water (160-185F) directly from the boiler even if the external storage is not first heated to this temperature, while the Garn generally must first heat its integrated storage to provide the very hot water. This is dependent on the amount of mixing that occurs in the Garn tank during the batch burn.

The amount of storage you have will dictate how long you will be able to provide needed heat between boiler burns. This is mostly about the math in calculating heat demand and stored btu's. Cordwood boilers need to be regularly fueled and if they cannot be tended during absences, a backup heat plan will be needed. In this regard, since it appears that you now have heating capacity installed, I would believe that your existing heating can be your backup and you shouldn't have to add another backup system.

If you want much more detailed test burn information on the Wood Gun E500 and the Garn WHS3200, send me a PM and I will provide you with the links to that information. Best of success on you biomass heating venture.


Wow Awesome reply! I will be sending you a pm for more information . Maybe a Wood gun or garn with a pellet backup would be my solution
 
Any tanks over there you can use for storage? Used propane?

I got mine in Moncton NB - just FYI, in case you or someone you know with a truck and/or trailer is driving by there sometime...
 
Any tanks over there you can use for storage? Used propane?

I got mine in Moncton NB - just FYI, in case you or someone you know with a truck and/or trailer is driving by there sometime...

Yeah if I go with the wood gun I will be prob using propane tanks for storage, lots in scrap yards
 
!!!!!!!!!

That would never fly for my wife or heck even for me,
70* all day
67* overnight

Ya, me too, pretty much exactly. Actually, the living room where everybody hangs out in the evenings is 72f when being used.
 
Jim, between the WG and the Froling, which would you say is the most pleasant to live with as far as restarting and the controls. Something that may be useful to the OP, I'm now being forced to mix -25% wood with a moisture content of 21-23% in with my 15-17% oak. Any experience with how the Froling would handle less than idea wood with the lambda controls? BTW I was going to ask where DP got a 70 class Froling (sure I read it was a 70 at DP somewhere). Really good info that 50 class Froling heating 6,000 way up in your area. Great post. Thanks
 
I was going to ask where DP got a 70 class Froling
If I said that, error. It is an FHG-L50 (170,000 btuh).
Jim, between the WG and the Froling, which would you say is the most pleasant to live with as far as restarting and the controls.
The WG has very basic controls: 1) aquastat for operating limit (180F); (2) aquastat for high limit (200F); 3) fan and purge switches/timers. It needs to be provided with return water protection. It is easy to start and restart. Although it can be operated without storage, the auto restart after idle can be very unpleasant, with a loud bang and emission of wood gas into the boiler area. Using it with storage and not overloading storage to cause idle eliminates this issue, and operation is then very smooth. It needs to be installed in a weather protected space.

The Froling is sweet all the way. Start is very easy, and then the computer takes over and runs the show. It will modulate the burn to a considerable extent and keep the burn efficient. It must be used with storage, and it will idle if storage/demand is not sufficient to accept btu output. Froling calls this "slumber." I would strongly recommend avoiding any slumbering. With sufficient storage, the Froling is about as it easy as it gets for a wood boiler, within my experience. The Froling comes with a loading unit and the computer controls the loading unit operation, which also provide return water protection. It comes with turbulators and a lever to move the turbs through the firetubes to keep them clean. And it looks great too. Although there would be reasons not to do this, it looks good enough to install in the living room (maybe a little exaggeration here). It needs to be installed in a weather protected space.

The Wood Gun is pretty forgiving on MC, and if I remember correctly, up to 30% is acceptable. And it can take fairly large size round wood, 2 foot lengths are easy to handle, and therefor the need for a lot of splitting is reduced. The Froling seems to work best on 18-20" splits, relatively small, up to about 4-6" diameter. 20% MC is recommended, although I know at DP the MC is variable between species, probably a range of 15-25% +/-. No adverse impact noticed.

Both have an operating/learning curve, which I think is true of all the gasification boilers. Having a mentor available for a novice to guide the path is a great advantage. Also, I think a person who has mechanical aptitude and a desire to learn, maybe some engineering/science-type inquisitiveness, are an advantage.
Really good info that 50 class Froling heating 6,000 way up in your area.
Our coldest this winter only has been down to about -25F. As that song goes, "no problem." Since we worked out the installation wrinkles with some replumbing for both the WG and the Froling, and adding storage for the WG, DP is about as pleased as reasonably possible. Savings in use of locally available wood bought at market rates, including staffing costs, over LP have been in the range of about $40,000/year.
 
Froling smaller splits, 4-6" plus some larger, 28-20" length.
My prior post had a typ. Should read "... 18-20" length."
 
Vigas makes a 100kw

Just under 10k here in the states. If you've got a source for a couple of 1k gallon old propane tanks.. You could likely be done with pumps and everything for around 15k.

JP
 
Vigas makes a 100kw

Just under 10k here in the states. If you've got a source for a couple of 1k gallon old propane tanks.. You could likely be done with pumps and everything for around 15k.

JP

They look pretty fancy and at that price it's half the price of everything I've been looking at, they look like a European company?
 
Local guy is AHONA. Mark is the owner. You won't find anyone talking trash on here about him. Well informed gentleman and is fantastic with service and support.

Slovakian boilers. He carries another brand or two. Vigas is a solid boiler. Been very happy with mine. Haven't heard many complaints about them on here.

JP
 
Local guy is AHONA. Mark is the owner. You won't find anyone talking trash on here about him. Well informed gentleman and is fantastic with service and support.

Slovakian boilers. He carries another brand or two. Vigas is a solid boiler. Been very happy with mine. Haven't heard many complaints about them on here.JP
I spoke to Mark a while back - a knowledgeable, honest guy.
 
Would that be large enough tho? I was thinking ill need about 500k btus for that heat load? I think Im more confused or overwhelmed than when I started lol
 
341k Btu... you need to KNOW what your heat load is. It's ok.. it's confusing to start. It's all math and physics. what are you judging your 500k number from?
 
Just found the load calculation he did, sorry for some reason i thought it was 500k but here is what he came up with. It was just a rough estimate from a friend of mine who is a hvac guy, with a 11000 sqft steel building and a 4000sqft home (8050 degree days) in my town and with R- 20 on steel building, coldest day load of about 20 btu/sq ft or a total of 300,000 btu/hr. between the buildings. He didn't take into account any windows or doors into the heat load calculation and he wasn't sure on a few things since he doesn't really do that kind of stuff often. How does that look to you guys?
 
Have you looked into the cost of a professional heat load analysis including air infiltration ("blower door") tests for your 2 buildings?

I'm a genetic cheapskate and have no idea how much they cost in your area but with the kind of money you might spend on heating that combined space it seems like it would be worth quite a lot to know for sure what size system(s) you need.

They can also let you know where you can do things to decrease your load and in what order you'll get the best payback.
 
windhager 26 KW and a garn 2000, for peaking and helping the fossil system during absences. How about that? much cheaper and less space than 2 2000's.
Edit:
Just saw the newer posts. 300,000 is a bunch. maybe a windhager XL and a GARN 2000
k
 
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No matter what.. you're talking about a good amount of money. You need to really know your requirements. Not a guess. The little money you spend on a plan, then any money you spend on air sealing and more insulation is MORE than covered in energy savings and not over buying on a new system.

I went at mine backwards.. I put an hour meter on my boiler (cost me just 20 bucks of so) and watched the boiler and the outside temps for a year. On the really cold days and nights.. I'd monitor the heat input. confirmed my estimates of heat load using measurements and online calculators.

google up 'calculating heat load' there's a solar site that has a good calculator.

JP
 
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I sent you a pm

gg
 
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