Outdoor wood boilers

[katmike]

Anyone out there care to share their experience with an outdoor wood boiler? I'd like to hear pros and cons, as I am considering a purchase.

For me the pros:
I live in a timber are so I have a fairly reliable fuel source.

Cons:
Have a neighbor (smoke).
I have a separate upstairs and downstairs furnaces, so installation would be bit more than "standard".

I am also wrestling with the cost benefit of this system (wood) vs just going geo-thermal.

If you have one or know someone that does, please share the experience. Thanks, Mike.

[Bizzybee]

Been looking myself, so no practical insight here.

Wood is cheapest, but if you can't raise the stack enough so you don't smoke your neighbor out, maybe look into a pellet burner? They aren't going to be cost effective if you don't have a local supplier for the pellets though.

I'm liking the geo-thermal idea too. Especially if I get into solar power at some point.

Good thread, I'll be watching to see what folks have to say about these. Seems like a see a few more of them every time I go up to Mich.

[Scott J.]

I use Geo-thermal for heating my house. It's 3200 SF and my electrical cost to heat/cool and all the rest of the electrical appliances costs me $143 a month. I have a pond that is the heat source. It cost me a little more to have the system installed. I had it figured out that I would get my payback in seven years verses using propane. It's been running for 11 years now without any problems.

I also have a fireplace that I rarely use. Cutting wood and hauling it is pretty labor intensive. It also brings quite a bit of dirt into the house. I just dropped seven 150' Douglas fir last week and I am not looking forward to bucking and splitting it. I must be getting soft in my older age.

[Sundance]

Early outdoor burners had boiler problems and leakage.
I have heard that has been resolved.

My biggest turn off is cost!! They run upward of $5000
plus installation and whatever plumbing is required.

I have a wood stove in the basement ($100 used) and
coupled with off peak electric and an air to air heat
pump it just didn't make economical sense to fork out
close to $7000 for an installed outdoor wood boiler.

Payback would be decades, not years for me.

By geothermal I assume your talking about a ground
source heat pump?? That is the route I'll be going in
a couple of years. I saw a video of a do it yourselfer
installing his own in the yard with a trencher. It did
not look overly complicated and did not require digging
up the whole yard. Lots of deep (10' - 12') trenches
though.

[Scott J.]

Sundance,
Yes it is a heat pump system. It has two inch pipe that goes out to the pond. Its a closed loop. The pipe is made into a mat that is sunk to the bottom using rocks, bricks or blocks tied to it. The run to the pond is about 80'. I put the pipes in that trench a little over two feet apart. I wish I had used a little more separation for more insulation. I have seen some company's advertizing that they can put the pipe down a well too.

Is the Devils lake area still going under water? Last time I flew over the area I was amazed at how many roads were covered over and barns flooded. Scott

[Hobie]

Take this with several grains of salt, because I admittedly know very little about geothermal heat systems. But I do know water systems, and I personally would be leary about putting anything down my well. The best of pipes and valves leak, and most heating loops have some sort of rust inhibitor in them. It's not worth the risk of contaminating the well.

I have considered the outdoor wood burner, but the ones I have seen are very smoky in operation, and the only location I have to out one is upwind. Will be interested in the opinions of others.

[MapMan]

Smoke - yikes!

When the unit is "coasting" in early and late heating seasons, the unit will be dampered so much that you (and your neighbor) will be cursing. Typically that will also be the time when the air is damp and still, so look forward to a low-lying blanket of smoke-fog. It will be fine when you are going full blast in the coldest part of winter.

I have a wood stove in the main part of the house, and to supplement it I am considering a corn/pellet stove for my sun porch. Should be easier to work with, as it is a through the wall installation.

Have fun!

MM

[drotec]

I've had a Central Boiler for 12 years now. Overall, I have been very satisfied with it.

I grew up with a woodstove in the house, and the outdoor furnace is so much better.

1. No dragging wood and dirt into the house.
2. No smoke or ashed in the house.
3. No chimney fires.
4. Burn any type of wood.
5. Larger logs = less cutting and splitting

Smoke can be an issue, but I find it no worse than my neighbors indoor woodstove. The central boiler has an on/off damper, and when it is off, I get very minimal smoke (about as much as a good bee smoker). Most smoke comes during the few minutes after transitioning from off to on. A forced air blower helps, but I believe the newer models are computer controlled and monitor stack temps and such and produce less smoke.

Another great thing that I figured out after owning it, is I could get local tree removal guys to deliver softwoods cut to length right to my yard for free. Seems they have a hard time getting rid of it and landfills are starting to charge them. I find the softwoods actually work better in the Fall and Spring as they don't produce huge piles of coals like hardwood.

Took my propane company a few years to figure out gas consumption though, I must have been their only customer who burnt more gas in the summer than the winter. The wood furnace does my domestic hot water in the winter, but I go back to propane for the summer

[MapMan]

I've had a Central Boiler for 12 years now. Overall, I have been very satisfied with it.

I do believe the reason a lot of the boilers which I see belching smoke (which is about 80% of them) don't have enough water capacity and tend to cycle too often. With small water capacity, the water reaches the set point temperature and the stove shuts down, and with a good load of wood in the firebox, it sits there and smolders. Now, on the other hand if your unit has a large water tank capacity, you can burn the total load of wood with good draft, burn and efficiency. You may only have to fire them up once a day or even every other day, of course depending on outdoor temperatures.

Perhaps making certain that the model is efficient and has a large capacity will minimize some of the smoke, but I know that more cities and small towns are banning their use. I have heard good things about the EKO line with their gasification boilers which substantially reduce the smoke particulates and emissions. They also use a lot less wood than conventional boilers.

MM

[Bizzybee]

Seems odd that there wouldn't be a level sensor or float switch in the reservoir to keep it auto filled. Think that would be the first mod I'd be making. What a pain.

[Zane]

Just what I have been waiting for! I have been looking also. Most my neighbors have them installed and a friend just did one using corn. His idea was his wife can carry a bucket of corn easier than bulky wood logs, makes sense I guess. They make some combo styles that you can burn different stuff too(wood,corn, pellets, even oil) but there seems to be more moving parts(ie more mx) but I havent talked to anyone w/ the combo's. I have been told to make sure you get a sturdy door. Some have warped due to extreme heat. We have alot of Hedge tree's that burn very hot so just be careful they say. I am considering one w/ and extra port to run a set of lines to my garage and future greenhouse. Cost here is about the same as Sundance. One thing for me is I live 7 miles from the nearest firestation and insurance doesnt want a fireplace in the house$$$$ so outside seems a better option, besides the cleanliness aspect.
-Another consideration is if a person loses power? How to heat w/o the blower going? Scott, remember the inagural storm power outage in the early 90's. Lost power for almost a week in Snohomish!!!
Sidenote- Im not sure comparing costs of the Lake Stevens,WA winters to Devils Lake,ND would even be close as it really doesnt get that cold in Western, WA.

[iddee]

drotec gave a very good description of them.

I have this one. You can also add a propane unit into it, for the times wood isn't feasible. Like when you are gone for days, or it is only needed at night, ETC.

www.taylormfg.com

Compared to propane, it paid for itself in 3 years. I get all my hardwoods delivered free from the tree services.

[honeyshack]

We have an outdoor wood stove.
It is good for the mess part. It is all out side.
We have it hooked into the electric furnance. There are two thermostates on the furnace. One to operate the fan for the outdoor stove and one for the electric furnace...just incase the outdoor runs out of wood
cheaper than electric
constistant heat, when the furnace gets filled.
Cons:
goes through alot of wood. We use more wood that with our indoor stove

you need to check the water regularly for the PH level. As water circulates it gains oxygen which will eat at the metal. Hard water is also hard on the system
Alot of smoke, but it only bothers the house in the spring time...maybe cause the windows are open then.
The logs are big, can be hard on the back, and the smoke billows out when filling the furnace. Got to be good at holding your breath
If you get a leak in the furnace it can be a bummer to weld in the inside of the furnace. father in law has been there and done that.
We have an electric boiler in the honey house. We really like it.

[berkshire bee]

Check local ordinances before buying. Our town and a few others have put a moratorium on permits for outdoor wood boilers because of neighborhood complaints about the short stacks and smoke output. People who already had them installed with permits can still use them, but the towns are trying to come up with reasonable guidelines .

[J-Bees]

Seems odd that there wouldn't be a level sensor or float switch in the reservoir to keep it auto filled. Think that would be the first mod I'd be making. What a pain.

But these stoves are NOT sealed they are OPEN. So there is no blow up like in the old steam boliers.

Also GeoThermal's do NoT go into your WeLL you have to have seperate holes dug. We ( the compainy I work for just done 36 well holes all of them are at 600' deep and are no more than 10' from one another) by doing these Geo Holes they will heat an cool the new school for less than 100 a month so I am told.......... other than that I know nothing about them.

Did get to help hook them up an they are all in a loop, two pipes down two pipes up.

[Bizzybee]

But these stoves are NOT sealed they are OPEN. So there is no blow up like in the old steam boliers.

I didn't suspect they were sealed, then you would have to deal with boiler inspections and all that garb. All the more easy to have a fill switch on them. I can't imagine why they wouldn't have that?

But maybe something going on there they aren't telling about? Not that they are hiding anything. Guess it would help to see one up close and personal.

[iddee]

Mine has a sight gauge next to the door, and a shut off on the line going in. It is very easy to look at the gauge each time you check or fill the stove, and open the valve when needed.

An internal flow valve would just be something else to go bad. You add chemicals to combat scale when filling for the season, so all that would be lost if the valve stuck open. Your stove would get too hot and warp, possibly causing it to rupture, if it stuck closed.

[Bizzybee]

Yeah but there are plenty of good switches that can be had these days that would out last the boiler I'm sure. Just one less thing to worry about and have to stand around waiting on.

What can I say, I gotta have gadgets.

[iddee]

Old mules killed fewer farmers than tractors. I prefer simple.

It's not the switch, but the valve that the switch operates that would cause the problem.

[Bizzybee]

Solenoid valve on the cold water line. Good for many years.