Who makes the MOST Efficient OWB?

[Deadman]

I'm getting ready to build a house and I am looking to purchase an OWB in roughely 6 months. I am wondering who makes the most efficient OWB?
I'll be heating a newly constructed house (well insulated) in Northern Wisconsin. The house will be roughely 2,000 square feet, and I also plan on heating my 3 stall garage (in-floor), and possibly in the future will add on another garage and MIGHT heat that.

I'll gladly spend more Money on a good quality boiler NOW, so I don't have to replace it in the near future, and also so it doesn't just burn a mountain of wood.

So what manufacturers do you recommend, or any special features to look for?

Thanks in advance!

 

[grandpatractor]

I'm getting ready to build a house and I am looking to purchase an OWB in roughely 6 months. I am wondering who makes the most efficient OWB?
I'll be heating a newly constructed house (well insulated) in Northern Wisconsin. The house will be roughely 2,000 square feet, and I also plan on heating my 3 stall garage (in-floor), and possibly in the future will add on another garage and MIGHT heat that.

I'll gladly spend more Money on a good quality boiler NOW, so I don't have to replace it in the near future, and also so it doesn't just burn a mountain of wood.

So what manufacturers do you recommend, or any special features to look for?

Thanks in advance!

Garn and Tarm make pretty effiecient boilers , I know that garn have to be put inside a building, which might work out with your shop or something

 

[Deadman]

I'd gladly build a small block building to put it in if that was needed to get into a better boiler.........do you have any links, or the companys full name? Then I could do some searching for more info. Thanks

 

[grandpatractor]

I'd gladly build a small block building to put it in if that was needed to get into a better boiler.........do you have any links, or the companys full name? Then I could do some searching for more info. Thanks

Check your pm's

 

[rx7145]

Your limited to Garn or Central Boiler. CB has no info on there web site I talked to a dealer and he said that they are all custom built and must be ordered from CB. They are about 10K. The garn is about 10K also. Look into both. Here is the garn link: http://www.dectra.net/garn/

P.S. Hardy also clams to have a gas unit. I have never seen one; somthing to look into.

 

[Deadman]

So with the Garn, you fire up and burn a couple loads of wood in a few hours, and then let the fire go out again.......and heat with the stored energy in the water you heated up????????????? Seems like a pain to have to start a fire every day or every other day. I think I'd rather have a maintained fire, but I'm a newbie at this boiler stuff.

 

[rx7145]

So with the Garn, you fire up and burn a couple loads of wood in a few hours, and then let the fire go out again.......and heat with the stored energy in the water you heated up????????????? Seems like a pain to have to start a fire every day or every other day. I think I'd rather have a maintained fire, but I'm a newbie at this boiler stuff.

I think that is how it works. They have a video that I saw the fire started very easy it might be because they "suck" the smoke out rather than blow it into the fire box.

They also said to stoke every other day. CB also said 48 hour burn time :monkey:

I still like the garn though.

 

[ktm rider]

. CB also said 48 hour burn time :monkey:

.

HORSE HOCKEY !!!

I will tell you why I think that. How can they actually tell you that you will have a 48 hour burn time? they don't know how big your house is, how well insulated, the wind and temps outside, the kind of wood being used. etc......this is just a sales ploy. If any manufacturer guarantees you a burn time that high, i would run away as fast as i could. they are feeding you a sales pitch and not being honest.:monkey:

 

[bassman]

I have a central boiler knockoff and love and hate it.
all of what I or anyone says will not make sence unless you are on your second year of burning wood to heat water to heat your home .
Tarm and garn and CB all work but you have to consider what will work for you ...
what wood can you get or have alot of.
garn and tarm need very dry good small wood where my boiler will burn almost anything and it may use up to 30% of what it burns and turn it into heat .
I can light up the sky with the fire that blows from my stack where as a tarm unit will warm your hands at the stack...
you have time . look and read .

If i was to do it all over I would install a tarm with a coal and oil burner add on so I could burn waste oil and coal and wood and pellets and grain and corn .


whatever you buy take the time to see it in action and stay the night or week so you know what you are getting into.

shayne

 

[windthrown]

Well, I dunno about there being no info on the Central Boiler(CB) site... unless you are referring to the new EPA certified boiler that they are working on. They have tons of stuff on their models, designs, in-home heating and retrofitting, etc. on their web site: www.centralboiler.com.

I have a CB here and I designed and installed the heating system, retrofitting the CB boiler into an existing solar hot water heater and hydronic floor heater. It works very very well. If I had it to do all over again, I would use this system again. We have gobs of wood here though, more than we can possibly burn from our own 85 acres of tree stand, or surrounding slash available after clear cutting. If I was here to build this house, I would have opted for building a Russian style fireplace in the center of the house. These are about as efficient as you can get.

The advantages of a CB type boiler is that you toss in wood and forget about it. You can cut large size logs that you do not have to split. You can burn just about any type of wood: hardwood, softwood, dry wood, wet wood, green wood, construction scrap wood, rotted wood, buggy wood, dry rot wood, sawdust, old furniture, and paper. Just about anything but treated wood. They also come complete so you can put them on a slab or gravel bed and hook them up. With some of the gassifier type boilers (ie, Greenwood) they are not fitted with an outside compartment or siding, and you have to put them in the house someplace, or build a shed for them. They also require smaller dry wood, and they have to be loaded a lot. They are a lot more efficient though. I know some people that got Greenwood systems and have regretted it. Most people I know with CBs like them, and the only real issue is that they are not that efficient. In the northeast they get a lot of complaints about smoke, but if anything, the boiler we have in full operation does not smoke that much, far less then our fireplace does, and only for short periods of time when the vent is open. Most of the time it hardly smokes at all.

Anyway, good luck with your decision...

 

[Deadman]

As for Wood, thats not going to be a problem for me. I have a couple of 40's with excellent wood on them. Mostly red oak, white oak, hard maple, beech, ash, Hickory and Ironwood!
I'll definately be burning seasoned wood, but it'd be nice to just cut big wood and be able to feed that right into a larger burner.

I really dislike starting a new fire every other day, so I'd rather go for a longer burning boiler (I think anyway). I'm really just looking for feedback on all the different types and styles, so this thread is priceless!
Thanks for all your comments and feedback.

 

[Farmerjon]

I am located in North West Indiana, have had a CB for seven winters. The only regret I have is I didn't purchase it earlier!!! My propane guy tried to wear out my driveway the first winter, oh I put 200 gallons in this spring because they were going to take the tank, we use if for our cookstove and dryer. Otherwise, forced air in the old part of the house, added on with the money saved from propane after the second year and put hot water in the slab. Also use it on our hot water heater so keep a fire going 24/7 365 days a year. Use pine slab in the summer for hot water. Hard woods in the winter. Can't tell you comparison for new stoves or other OWB as this is my first and only. Had one pump go bad, they paid for it and shipping. Blew a fuse on the vent door, otherwise, fill and forget. Consumption, a wheel barrow a day if zero or below. Yep, other post was correct, green wood, split wood, rounds, spalted, whatever, it will consume it.

 

[hanko]

I'm getting ready to build a house and I am looking to purchase an OWB in roughely 6 months. I am wondering who makes the most efficient OWB?
I'll be heating a newly constructed house (well insulated) in Northern Wisconsin. The house will be roughely 2,000 square feet, and I also plan on heating my 3 stall garage (in-floor), and possibly in the future will add on another garage and MIGHT heat that.

I'll gladly spend more Money on a good quality boiler NOW, so I don't have to replace it in the near future, and also so it doesn't just burn a mountain of wood.

So what manufacturers do you recommend, or any special features to look for?

Thanks in advance!

. I will try to answer your question, none of them are very efficient.

 

[Deadman]

How many cords of wood are you guys burning to heat a house? Just tell me what state you are in and how big of house and how good its insulated, and it'll be an estimate anyway.

 

[beerman6]

6-10.mid Mich,1440 sqft plus basement,poorly insulated

 

[Farmerjon]

2400 sq ft. half old house new windows no insulation, new part well insulated, new efficient windows.

12 pickup loads. I have never bought or sold wood by a specific value other than pickup load. Never sold wood actually. My pickup loads are what fit in/on the bed (stuffed) but the loads being sold are even across the top of the bedside some not stacked in the bed. Sorry don't have the specific measurement.

 

[Boundaryh20]

Take a serious look at the gasification units...

Bought a house with an older OWB about 4yrs ago. The unit lasted about 1.5yrs and sprang a leak. Since I was now sold on a OWB, I started shopping around and found this site and others discovering the gasification units.

Having ended up buying a gasification unit (EkoLine), I would not go back to a regular OWB. The main reason is wood usage. I, also, have all the wood in the world, but now I use about a third of the wood I did with the OWB. I also heat all my domestic hot water with it. And I usually keep my garage at 70F.

Disadvantage is that the wood must be dry and you should have a hot water storage tank like the Garn.

If you are building...don't mess around...put in hot water heat (in floor) and a pressurized OWB or gasification unit.

Also, I have my propane boiler 'in-line' with the system that will 'take-over' if I want it to when the boiler runs out of fuel. Currently I don't even have the pilot lit.

Good-luck,
Bryan

 

[windthrown]

I really dislike starting a new fire every other day, so I'd rather go for a longer burning boiler (I think anyway). I'm really just looking for feedback on all the different types and styles, so this thread is priceless!
Thanks for all your comments and feedback.

As far as I know, there is no all-wood OWB that will burn more than about 24 hours. You can get a larger system that holds more wood, and has more water in the boiler so that the wood last longer and the water stores more heat energy. But, there have been many debates here on AS and other sites over burn times, and if they will even go 24 hours w/o refilling. 24 hours is stretching it where you live. I can get a 24 hour burn at most down to about 40 degrees F. But in a cold snap (15 degrees here last year) I can get about 16 hours at most. That is filling the boiler with oak or madrone (hard dense dry wood) and having a good set of coals at the end to toss in more logs and its self-ignites for the next round of burning. If I use fir or pine, there are no coals and usually have to add wood and restart the fire with paper.

There are mutually exclusive aspects of OWB burners vs. wood gassifiers; OWBs will take a lot of wood and run in cycles and burn for a while until the preset temp is reached and then they shut down until the temp drops to about 10 degrees below the set temp. They are basically starved-air systems. The disadvantage of OWBs is that they are less efficient; the advantage is that they have long burning times and they can burn large rounds of wood. I get more efficnent burning out of our OWB by feeding it less wood more times a day, typically once in the morning, once in the afternoon, and once last at night (usually after reading and writing on AS just before going to bed). This reduces the process of charcoal making and wood gas escaping durnig the off-modes. Wood gassifiers (like Russian style fireplaces), in contrast, take a small amount of wood and burn at a very hot temperature for a short period of time. They are far more efficient, but they have to be fed small wood and lighted several times a day. They are also more EPA friendly and have less smoke than a typical OWB.

Basically what it comes down to is that OWBs store potential energy in the form of wood burning over a longer period of time. Gassifiers and Russian fireboxes store released energy in water or brick and not in the wood. So it is a trade-off in design and use model of these types of heating systems. Note also that there are combination systems out there, like oil and LP and NG combined with wood burners. There are also corn and coal combined with wood burners. Here we have wood and more wood, so we have a wood-only OWB.

 

[woodchuck76]

I Have a CB 4030.I'm heating my house of 1400 sq ft. 700 sq ft of garage space and hot water.Insulation R-19 in the ceiling ,2X6 wall construction.Use around 10-12 cords of seasoned wood. From October to May.

 

[windthrown]

How many cords of wood are you guys burning to heat a house? Just tell me what state you are in and how big of house and how good its insulated, and it'll be an estimate anyway.

We use about 8 cords of dense seasoned hardwood here (oak, madrone, alder, and doug fir mostly). The amount varies from year to year though, as temps here vary a lot between years. House is about 2,000 sq ft., modern with heaps of insulation, but has gobs of non-covered 2-pane windows and skylights, and a lofted ceiling (heat sinks). We also have a second clothes washer for cleaning sheep fleeces. Already had a floor loop, and an electric boiler. I used two comparisons to estimate OWB size needed: one was cubic feet of house air space and the other was to match the size of the electric floor loop boiler and water heater in watts. Both came out to about the same number, which I then doubled (std. engineering practice). That turned out to be the same energy as the smallest Central Boiler unit rating that they had at the time (a CL 4436, at 250k BTUs). We could have used one of their newer smaller systems, had they been available at that time. But we can expand it to heat a greenhouse or an enclosed shop in future, and it is nice to have a larger system in the coldest part of winter. Taken care of, these systems will not rust or leak. You can do a search on OWBs here on AS and find debates about stainless steel, fan driven or convction, flat plate vs. side arm Hx, company types, PEX lines and insulation, and different models available and what people think of them. There is also a lot of discussion and flame wars on these over on the Mother Earth News forum.