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[ChrHerrman]

I live in a 300 year old uninsulated farmhouse in SE PA and am considering buying a OWB. Currently, we have an oil boiler and a small indoor wood stove in the stone kitchen. Our house is 2600 sq ft, heated by hot water baseboard.

The local dealer suggested a 200 css because of the old, uninsulated house and some drafty windows. We are going to start by putting in a new oil boiler this year to replace the 30 year old existing one, so that should save us some on oil consumption. To get the 200 css delivered and installed would be right around $10k so we have to budget for that until next winter, but I have heard a lot of bad things about OWBs hear lately, more than good things. I have heard several people say that they installed one, and could not keep their old house warm, so they went back to conventional heating (oil, gas). I have also heard that new oil boilers are very efficient and rather inexpensive compared to an OWB, it makes me wonder if we should not just heat with oil.  I enjoy cutting firewood and sell 8-10 cords a year, but have thought about just using it to heat our entire home and hot water. I have a small tree business and access to woodlots, so I am not worried about access to firewood. I think we will use a new oil boiler this year and in the spring compare it to what an OWB would do. We also thought about putting a propane firplace in the stone bedroom upstairs for ambiance, but I think it would actually heat that bedroom.

A couple general questions-

How much wood would we burn compared to oil we would use with a new boiler?

Does it sound like we could get by with a 100 css with a small indoor wood stove in the kitchen and a gas fireplace upstairs, or should we go with a 200 css? (about $1200 difference)

What is the maximum distance we should put the OWB from our home?

Can we burn green wood as well as pine?

Is there a lot of smoke from the OWB?

Does anybody have an indoor wood boiler and any comments about those?

Thanks a lot I look forward to hearing from you!

[Scott7m]

A lot of people who have old houses use outdoor wood boilers and love the heat.  You will hear a lot of false claims that could be due to poor installation or who knows what. 

Look at the bright side, your wood is free of cost to you and your cutting it anyway.   I hear some crazy claims on here of people burning 10-12 cords per winter.  With proper installations I've no found that to be the case.  I'm a lil further south but 8-10 truck loads seems to be the norm around here. 

DO NOT go undersized on an outdoor wood boiler, you wont need the indoor unit if you get one that is properly sized for your homes needs. 

With quality insulated pex you can have your boiler as much as 250 feet away with the right pump, there is some line that is so good the water can leave your stove at 180 and travel 150 feet and the temperature stiill be 179.6.  So thats not an issue if you use good line.

As long as you dont buy a gasification unit, you can burn green wood or whatever you would like. 

OWB, smoke some yes, dryer wood results in much less smoke of course.  Most people will add a chimney extension onto there stove to get the smoke up higher to help remove it from there area.  On cold rainy nights you might notice smoke hanging around a bit more.  But for most its definetly not a problem.

[willieG]

youday your old oil burner is about 30 years old (lets use it for comparison as it is likely 50 to 65 percent efficient the same as a non gasification out door boiler)

it takes about 7 gallons of heating oil to make 1 million BTU so to make 20 million (about equal to a cord of good hardwood) it would take 20 x7 or 144 gallons of oil to equal a cord of good dry hardwood. figure out how many gallons of oil you used last year and you will see how many cords of wood you will need (very close) and I will bet it is at least ten cords if not 14 in your older home
todays oil stoves are much more efficent and you woul use a lot less oil
lets say you get a new oil stove that is 95 percent efficient and you save at least 30 percent of you last years oil bill..if you were to put that savings towards insulation and windows every year and made your home much more energy efficient you could spend this savings every year and not have to cut wood. But if you like to cut wood as a lot of us do then by all means get an outdoor boiler
Don't let the sales guy tell you about 24 hour burns on a load (maybe in May)
if you live in an old farmhouse poorly insulated you need to improve that situation before doing anything else in my opinion

pine wood is about 3 to 4 million btu less per cord and if it is wet only around 10 million (and remember these are usable BTU but you must cut that in half as your boiler is only 50 to 60 percent efficient

i heat a home such as yours but i have done a lot of insulating and when my underground pipes were good (new) i used between 8 and 10 cords of wood

[MattyNH]

What I tell people that are interested in a outside wood furnace is..You gotta like doing wood and its a expense up front.. I burn about 9 -10 cord  in a 7 month period for heat and hot water..Like WilleG said dont let the sales guy  tell you 24 hr burn. I know a lot of people that own OWB's and its filled twice a day in the dead of winter..Less when its warm out... Some are backed up by propane if fire goes out (central boiler) You can burn pine..Green wood does smoke esp green pine.. Seasoned wood youll get the most btu's..The new epa furnaces dont smoke like the older ones..What ive heard you cant burn green wood in them and the wood is a lot smaller.There is a option of pellet and corn burning OWB which are pretty much smokeless..My furnace is 90 feet from my house..Some OWB claim up to 500 ft...Either way being a old house its gonna take a lot to keep warm..Wood is always cheaper!...Free wood free heat..Beats paying for that bill for foreign oil

[ChrHerrman]

Thanks for all the good input, I really appreciate it. I plan on redoing some windows and insulation as soon as I save some money, because I can see the wood I would be burning being wasted right there. Do you have to have a generator back up in case the power goes out in order to circulate the water? I know a friend with an indoor wood boiler that has to fire up a generator as soon as he loses power or else he will bust a pipe due to boiling water. What do you think is better, putting the OWB closer to the house so it is closer to load (30 ft), or closer to the driveway where I can dump the wood right out next to it (100 ft)? Any other tips or suggestions would also be appreciated. Thanks for the quick responses. This is a great site!

[ChrHerrman]

A couple more questions I thought of-

Has anybody had an indoor water boiler and how do they compare?

What is better mild steel or stainless steel and why?

Do you guys split your wood small (fireplace size) or just throw entire logs in?

[yoderheating]

 Just a few thoughts I had on your questions.
 It is better to oversize your furnace rather than undersizing it.  A well built furnace will only burn the amount of wood that it needs so on that is slightly oversized will just give you a longer burn time. If you were to undersize your furnace it may mean you will be out in the middle of the night loading wood.
 Outdoor furnaces do work well with indoor boiler systems so long as the indoor boiler isn't normally running above 180.  You may have a problem if your system is set up to run high temps in order to heat your home.  I normally tell people I can match or beat a system that is designed to run at 160 or below.
 Not all of the new gassification units are the same. The one I sell ( Heat Master G200) burns green wood just as well as dry wood. You still don't get as many btu's out of green pine but the furnace will burn it without producing smoke.
 If you are concerned about wood consumption try and buy a furnace with an additional bypass. Our High Efficiency models have the additional bypass and are 25% more efficient than a traditional outdoor furnace.
 Good Luck.

[CORVAIRWILD]

Hi, I'm a newby, and posted a general intro to myself here...

http://outdoorwoodfurnaceinfo.com/forum/index.php?topic=706.0

So I suppose I should buy something that's available locally, far NE upstate NY, Plattsburgh, 12901

1,200 SqFt log house with a 60x90 Warehouse

Central Boiler is one brand sold nearby. A friend said not to look at anything but Heatmore, but I suppose that's like a car brand. BTW, I collect Corvairs, drive an '84 Suburban 4x4 Diesel as a DD, and a '93 Hyundai Excel as a commuter car

I have hundreds of acres of woodlot, but I've never done more than cut down an occasional tree to clear a logging road. I don't think I've ever run a log splitter! The wood is 15 miles away, and plenty of folks sell cut and split cordwood locally, as we're just outside the Adirondacks

[kjw58]

For anyone contemplating a owb I have one word for you     GASSIFICATION!!!    its the only way to go.

[farmeral]

As far as distance from the house, in my experience if you use the right type of piping, it is very expensive.  You will have to balance the cost against having the wood mess and smoke farther from the house.
I would say if you like cutting wood and have a supply of your own, you will like having an OWB.

[leguftek]

Maximum distance of hosing recommendation is 130 ft.
Do not undersize.....calculate what you need and then buy the next bigger model.
To do the full deal....don't start unless you have access to about $11k. Burner, hose, fittings, valves, exchanger, hot water heater exchanger, pump, trencher, romex electrical line in trench, etc.
If you are in a highly regulated area then go with an EPA approved model which most codes acknowledge and they also come with tax rebates sometimes.

I own and use a Cadillac 5600 very happily to heat a 6000+ sf house and a 2000 sf shop.  Two underground lines over 120' each, two pumps, 3 exchangers, and a modine.  Strong recommendation for this brand and model.

[tbone]

I have mine 100' from my house where I can easily unload my wood supply...and if I ever need to...room for a triaxle delivery.  Sure you have an expense increase with the extra pex, but your wood handling or processing will be less.  No need to add more work. 

[RSI]

I haven't seen it mentioned yet but doesn't PA require EPA phase 2 certified OWB's now? If so there are not a lot of choices left. (The Heatmaster mentioned above is one choice)

If you burn under 10 cord of wood in an uninsulated house like that I would be really surprised. With a gasification boiler and hardwood it might be close.

You can put the boiler as far from the house as you want but the farther you go the more it costs and you will have less available heat (less GPMs) the farther you go unless you get bigger pipe. You could probably go 300' with 1-1/4" if you had to.

Most outdoor boilers are not pressurized so can't blow up and most won't boil over unless they have leaking door seals and it is warm outside.

[Ridgekid]

Yes.  Pa requires EPA approved OWF's.