Newbie Needs Help with OWB selection!

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Natasha

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Oct 24, 2013
4
NJ
First of all to anyone that reads this thank you for taking the time, I know questions from the uninformed can be repetitive and annoying.

I would like to purchase the highest efficiency exterior wood burner/gasification furnace to heat my house (5000+/- sq ft) and possibly some day a pool.

I am absolutely and totally clueless. Is there a manufacturer that is considered to be the "cadillac" of wood furnaces? There is so much info on this site it is hard to digest and any help would be greatly appreciated. I want the cleanest burning and most efficient equipment, I don't mind paying a little more if it is well made and will last. Central Boiler was recommended to me but again I have no idea if there's are actually decent furnaces or not.

thanks in advance!!
 
If cleanest burning & most efficient are the first priorities, an OWB is not the first choice.

Those priorities are met with an indoor gasification boiler (either installed in the house or an outbuilding), and storage.
 
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First off, welcome to the board! There is no better source for info on wood boilers on the interweb than hearth.com as far as I can tell.

You're going to have quite a load with 5k square feet. I assume the pool would only be heated in the summer so that shouldn't really be "on top of" the heat load of your house.

If you're willing to "spend a little more for quality" I would highly recommend you consider building yourself a decent shed and installing within it a Garn. Almost every boiler out there is going to have good reviews and "not so good" reviews. The Garn, in my experience, is an excpetion to that. They are bullet proof. And made in the USA to boot.

Central Boiler is another well know USA made brand that you've already been made aware of. Depending on the site you visit you'll either find people passionately supporting them, or passionately bashing them. Unfortunately (in my opinion) this site is more the latter lately. Regardless of the reputation they are indeed an outdoor boiler and there will be some challenges in terms of efficiencies for anything sitting outside all day.

If it were my money to spend it would be a Garn, hands down. If the Garn Jr had been around when I built my system I can all but promise I would have bought that instead of my EKO. That being said, my EKO rocks and I can't say enough good things about it in spite of it being non-US made.
 
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Welcome Natasha, It's not often this group of crusty guys has a lady visit. Just imagine you've walked into a old country store with a bunch of young and old guys sitting around a pot belly stove. The guys here will make you at home.

Our home is about the same size as yours and we love whole heating with wood process during the winter. You'll get lots of good suggestions about calculating the load (heat) your home needs so you can properly size your boiler. Step one for me was that I had to keep my forced air system (ducts and blower). You'll read here about radiant versus forced air heat. Google that. I agree with Stee above, I was tempted to install a Garn also, but it's not as happy with a forced air system (per the pro installers here). Do a search and this discussion has come up often. Not long ago there was a thread trying to list the top 10. I think once you narrow it down to the top 5, 6, 7 manufacturers they are all well liked. Maybe someone will remember how to link you to a top 10 boiler discussion about 1-2 months ago.
 


Give the Garn a serious look !

Welcome to "hearth " .Experience is a good but sometimes expensive teacher .Take your time to digest all the information and make your first choice the right one .
Good luck.
 

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Hello Natasha,

An accurate heat loss calculation is the best place to start. Without that the next best info would be your annual heating needs (gallons of oil or propane, therms of natural gas, Kwh of electric). Share this with us if possible as it will make it easier to make recommendations on boiler sizing but it will also give you an idea of how much wood you are looking at needing to process/handle on a yearly basis. This could be substantial depending on you heat load which leads into.....

Are you experienced with the whole cutting/splitting/stacking/seasoning thing? If you are or are VERY committed to learning AND you have an endless supply of "free" wood than a cord wood boiler could be a great option.
If you are not absolutely, positively committed to this labor of love than another option could be a pellet boiler. Search the site for Windhager. Very impressive. You wont likely save as much $ with this option but you wont have to dedicate nearly the time that solid fuel boilers require either and this is a trade of worth considering.

What is your current heat distribution system? Pics of you existing system could also be helpful.

Noah
 
First of all to anyone that reads this thank you for taking the time, I know questions from the uninformed can be repetitive and annoying.

I would like to purchase the highest efficiency exterior wood burner/gasification furnace to heat my house (5000+/- sq ft) and possibly some day a pool.

I am absolutely and totally clueless. Is there a manufacturer that is considered to be the "cadillac" of wood furnaces? There is so much info on this site it is hard to digest and any help would be greatly appreciated. I want the cleanest burning and most efficient equipment, I don't mind paying a little more if it is well made and will last. Central Boiler was recommended to me but again I have no idea if there's are actually decent furnaces or not.

thanks in advance!!


A Mahoning can burn both wood and coal and they are very popular.

The issue is a CLEAN BURN AND MAINTAININGA CLEAN BURN.

This will allow you to use less wood because there will be little to no smoke



The Garn is a very good unit but it must be indoors in an insulated building.


You have not discussed how much in funding you are able to spend AND HOW MUCH TIME YOU HAVE
TO MESS WITH ONE OF THOSE BLOODY THINGS!!!!!!!




Save your money;

For the existing load you have or additional load you plan on having a coal stoker
is the only thing that will handle it.

Anthracite is clean burning with no smoke and produces little ash in a stoker.


THE coal stoker will not piss off the neighbors ever and cause problems.

There is a reason outdoor boilers are called smoke dragons Natasha.

these boilers spend a lot of time idling once the water temperature is reached and
you lose all that heat energy in the wood because the fire is smoldering.

AN EFM coal stoker will cycle on and off and run at a minimum burn to keep a coal fire going
and will not smoke at idle-high limit temperature which shuts the damper off.





For one example.

The EFM coal stokers have been in use for many years and are very well built and
have a closed hydronic system.

They work the year round if you have a domestic loop installed, and even the smallest
one could handle your heat load and a pool.


A coal stoker like the EFM has an auger feeding the coal into a burn pot which has a
fan blowing combustion air into the burn pot via the auger tube.


AN outdoor wood boiler will burn a tremendous amount of wood if you are not right there to tend it by
regulating how much wood you throw in there every once and a while to keep a hot fire going.

Do you own a wood splitter or chainsaw or are you able to buy wood locally?

IF you purchased even the smallest EFM Coal Stoker you could buy a tractor trailer load of pea coal and
it would last you at least five and possibly ten years with your heating load.
coal does not rot or decay as quickly as wood does.

YOU have to decide how much time you are willing to spend feeding a smoke dragon.

if you have close neighbors you will want a coal stoker because it burns clean.

A closed system will also not require water treatment like an open system.
 
For the existing load you have or additional load you plan on having a coal stoker
is the only thing that will handle it.

Sorry, that is just plain wrong.

Check out heatermans 'A pair of windhaggers..' thread a couple pages down to see how big a load pellets can heat, or any of jebatty's very informative postings on his Deep Portage experiences in heating institutional settings quite well with any one of three different brands of wood boilers. There are all kinds of options available.

Coal might have it's places in certain circumstances, but those are relatively few - or else we'd all be doing it.

Are you a coal salesman?
 
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I would like to purchase the highest efficiency exterior wood burner/gasification furnace to heat my house (5000+/- sq ft) and possibly some day a pool.

I want the cleanest burning and most efficient equipment, I don't mind paying a little more if it is well made and will last.

As mentioned above more info required on your current energy usage & other info on your current heating system. This will relate to folks recommending the correct size of boiler for your situation.

Will the future pool be a summer only or all year? Olympic size pool or slightly smaller? Pellet boilers are an option as well, up to you really as it will be a trade off time cutting, hauling, splitting & stacking vs cost of pellets. Basically a time/money trade off.

Pellet boilers (good ones) will be higher eff. than cordwood due to the MC of the pellets.

Plenty of options to be sure but folks will need more info on your situation in order to get you started on your search.

Welcome to the forum. Great bunch of folks here.
 
Sorry, that is just plain wrong.

Check out heatermans 'A pair of windhaggers..' thread a couple pages down to see how big a load pellets can heat, or any of jebatty's very informative postings on his Deep Portage experiences in heating institutional settings quite well with any one of three different brands of wood boilers. There are all kinds of options available.

Coal might have it's places in certain circumstances, but those are relatively few - or else we'd all be doing it.

Are you a coal salesman?

----------------------------------------------------------------------------------------------------------------------------------------------------------------------

No I am not in coal sales, I burn wood and coal both
.
I lot of people burn coal in the northeastern states, Canada and Alaska as well.


She offered little to no information about her situation
so I offered an opinion that's all I did.


AS I mention to so many posters on a another forum "Help us to help us help YOU"
 
First of all to anyone that reads this thank you for taking the time,
I would like to purchase the highest efficiency exterior wood burner/gasification furnace
I am absolutely and totally clueless. Is there a manufacturer that is considered to be the "cadillac" of wood furnaces? .

I have been burning wood in boilers for many years. The first just a water jacket around a barrel type firebox (Smoke Dragon). The second, a cast iron down drafting triple pass creosote dripping unit later connected to storage to become the most terrifying creosote producing burner I have ever owned and lastly for 30 + years a Gasification boiler with storage and piece of mind.
The biggest problem with any wood burning boiler is that in most cases you cannot match the boiler output to the load on a consistent basis causing idling and idling is where the problems begins. In most cases the firebox is surrounded by water which can quickly reduce the firebox temperatures - a perfect environment to make creosote. When there is no load and the oxygen is cut to the fire, the fire goes into smolder mode; the beginning of the creosote producing time and also loss of efficiency. Even the best outdoor gasification boiler can have problems if there is too much idle time and the high temperature burn time is too short.

If you want the "cadillac", my opinion is that the Garn meets the bill but it will require its own building. The problem of matching the load to the boiler's output is solved by the boiler's own internal storage. One high temperature burn (batch burn) with no idling and the load is drawn from its storage only as needed.
Another aspect that many wanting to install an outside boiler do not consider is the expense of the underground lines that deliver the heat to its load.

There are several outdoor gasification boilers, one being the Portage & Main Optimizer but I have only seen one in operation and it has problems with there not being enough load for its output. There are many of these boiler out there but their owners are reluctant to get involved in these discussions. SO IF YOU OWN ONE, get involved and tell the hows and the whys needed to make the boiler operate successfully.

The below pdf is the section from the Jetstream boiler manual on the principals of gasification and storage. It explains it much better than I can.
 

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To offer a bit more info. My house is brand new, less than one year old. I have a hydronic forced hot air system throughout. I live in 65 acres in the middle of 2000 empty acres of parkland, so, no neighbors. I am farm assessed for forestry management and I am converting some of my property to fields for livestock and I have stacks of wood as far as the eye can see. It is borderline asinine for me to not take advantage of the free heat I can generate from all of this wood. I don't know if it matters but I have a lot of ash trees. I am not going to put in an enormous pool and I will probably only heat it in the summer but I want to size my system accordingly. I spoke to a Garn distributor and while slightly more expensive than what I had originally anticipated it is within my budget. In my town I would have to house the furnace in a separate structure so that is a non issue and something for which I had already planned.

I don't really have an interest in coal, or I didn't, because I have so much wood I just want to use that.

I am committed to the process of using wood, my property already requires maintenance and this is in line with what I am already doing.

Thank you all again for all of the information this has given me a significant leg up in my research.
 
http://www.builditsolar.com/References/Calculators/HeatLoss/HeatLoss.htm

This calculator should give a rough idea of your hourly heat load.
Example if your hourly house load is 60,000 BTUs per hour. The Portage & Main Optimizer 250 has a maximum output of 200,000 BTUs per hour and water storage capacity of 250 gallons. If the boiler fire shuts down at 195 degrees and the fire comes back to life at 170 degrees, the 250 gallons of storage allows for 1 hour of idle time and 20 minutes of burn time.
So only the people that operate these boilers can tell you how successful they are.
 
You're on the right track. If you've got the space for it & can accomodate it, I really don't think you can go wrong with a Garn.

One thing you can do while you're deciding on the details - make sure you get your wood in good shape for burning. That means seasoned - cut, split & stacked for some time, in a place where air can move through & around it. Everything that burns wood should be burning only well-seasoned wood [and not green] anyway, but gasifiers are generally more fussy about it (so to speak) in order to attain their potentials.
 
They are permitted if they are inside a separate structure, so I have to build a shed in which to house it regardless. The rule is silly but that's what it is.
 
I'm waiting for Heaterman or someone to discuss why the Garn is more ideal for radiant heat versus forced air. Not dinging the Garn, just remember an old discussion explaining why the Garn was a more happy match with radiant and low temps vs ductwork.
 
I'm waiting for Heaterman or someone to discuss why the Garn is more ideal for radiant heat versus forced air. Not dinging the Garn, just remember an old discussion explaining why the Garn was a more happy match with radiant and low temps vs ductwork.
One thing is that Garns start to lose efficiency as the water temperature inside rises above a certain point, so if you need water up over 180 degF then a Garn suffers certain amount of relative disadvantage to units that work better at higher water temperatures. Radiant systems don't need water to be all that hot. This is not a fault of the Garn, it's just a disadvantage as a result of the sweet spot they aimed for in their design being less compatible with higher temperatures.

Another is that Garns typically require a water to water HX, and it's a lot easier to get 120 degF out of a HX with 175 degF input than it is to get 180 degF out of a HX with 185 degF input.

And finally, radiant systems naturally take full advantage of heat storage, Garn or otherwise, since the return water to storage is way down around 100 degF or less even.
 
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Thanks EW, I didn't remember the specifics, but when I kicked around putting in a Garn about a year ago vs adding storage to the BioMass this came up. Natasha's situation is much like mine since she also has ductwork. Natasha, you need to see the picture of "_dan" setup. You other guys with jazzy systems send her pics.... not me.... but I'm still proud of my barn.
 
I'm waiting for Heaterman or someone to discuss why the Garn is more ideal for radiant heat versus forced air. Not dinging the Garn, just remember an old discussion explaining why the Garn was a more happy match with radiant and low temps vs ductwork.


The issue is not that the Garn is any more or less efficient than any other wood boiler when considering high or low water temps. Any and all boilers are more efficient when firing into cooler water regardless of whether they are fired with wood. coal. oil or gas.

The point to be made is that any typical forced air/duct system usually demands a minimum water temp of 140* to deliver adequate heat to the structure. This is inherent in the nature of the delivery system, not so much any particular boiler. I have seen many Garns that function quite well within the temperature requirements dictated by a forced air system.
What is lost on a forced air system/Garn combo....or any wood boiler/storage system for that matter, is the ability to heat with low temperature water typically used for a radiant floor design. This limits the allowable "swing" before having to reload or re-fire the boiler.

The math is pretty simple... A boiler system holding 1000 gallons of water will "unload" 416,500 btus when you drop the water temperature from 190* down to 140*, which is about the minimum temp for a water to air heating coil typical of a forced air system.
If the same boiler is connected to a radiant floor system that can provide heat with only 110* water, it can now deliver 666,400 btu's before having to stoke it up again.It's just a matter of what the heating system demands and if it can work with lower temps, you can take full advantage of the characteristics that are particular to the Garn.

The advantage that Garn has over a normal gasifier in an application using temps <140* is that condensation and/or cold shocking the boiler is not an issue. A person can start a fire in a Garn at 110-120* and just let it run with no tempering valve or other protection. This is definitely not the case with other wood boilers.
 
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The Garn I believe has addressed this issue for higher temperature needs of over 150 degrees , with its larger storage capacity units of 1,500 and 2,000 gallons! You still have ample time between firings .
With the Jetstream when just heating DHW in the summer I let the storage drop to 120 and then take it back up to 195 , there is marked higher efficiency at these lower temperatures .
But the need for boiler protection I believe takes away this advantage for its newer cousins .
 
Natasha, if you want the straight scoop on a Garn give Jim Korzack a call at 908-852-9008. He's the Garn rep for NJ and owns one himself. He's a straight shooter and will tell you if a Garn is right for you or not.
 
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The issue is not that the Garn is any more or less efficient than any other wood boiler when considering high or low water temps. Any and all boilers are more efficient when firing into cooler water regardless of whether they are fired with wood. coal. oil or gas.
No, as you well know the efficiency can be measured according to the temperature and composition of the flue gases. As the water temperature rises in a Garn through the burn cycle the flue gases get hotter and efficiency goes down. A gasifier with flue temperature control can reduce burn rate and maintain efficiency.
 
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