What's wrong with this idea?

[gregoryinns]

I've been watching my neighbors rush to put in new outdoor wood boilers (variety of brands, variety of reasons). I like the idea of burning wood (we did this as a family when I was 10-22), but I don't think it's the perfect solution.

Concerns with existing OWBs:

1) Notoriously inefficient compared to "indoor" wood gasifiers (simply this: uses more wood).
2) Will freeze if you have to leave for an extended period of time (I know you can get a "backup" system installed in some OWBs, but for lots of extra $)

Why not do this:

Buy an "indoor" wood gasifier and place it in a small (10x10), insulated building with a small propane heater. The result is you use a lot less wood, and you don't have to be married to it (you can let it go out, if necessary).

I have to add up all the costs, but even considering having to construct a small, insulated building and put up a chimney, I just can't believe it's a lot more than what these guys are paying for their OWBs.

 

[oneoldbanjo]

For me the decision to install an OWB was influenced by not wanting the smell, smoke or dirt from wood in my house. I researched building a seperate room on the side of my basement that would only have a door to the outside and be completely seperated from my house - any kind of woodburner other than a fireplace would increase my insurance premium by 50% according to my insurance agent.

I also have seen/talked to lots of people that have installed Woodburners in their house and have had someone in the house that was allergic to smoke and they had to stop using it.

My outdoor woodburner will not freeze in the winter. The thermostat for our OWB is set at 68 and the one for our regular furnace is set at 65. If I leave for an extended period the indoor furnace will sense the temperature drop and start to heat the house, and the heat exchanger will carry warm water out to the OWB and keep it from freezing (in theory) - What actaully happens however is that I have 2 neighbors with OWB's and they will come over and put wood in my OWB while I am gone.

I expect my OWB will last a long time - and I hope that by the time I need a new one the technology is better and they are cleaner and more efficient. Until that time however my house is very well insulated and my land has enough trees that it drops enough dead trees and limbs to keep me warm all winter. My neighbors are a long way away from me and smoke from my OWB is never a problem.

 

[mtfallsmikey]

There is another well-known website where the gasifier is king...it's easy to find. OWB's are kind of frowned upon there. Gasifiers are good, but..

1. They are pricey $$$
2. Most require good dry wood
3. Most need/require large capacity storage for HW

The OWB fit my needs because...

1. No basement
2. Built-in water storage
3. No mess inside the house
4. Insurance issues
5. No close neighbors

:deadhorse:

 

[gregoryinns]

Clarification: when I was talking about a small building, I was envisioning a detached structure about 100 feet from my house (similar to how many people locate their OWBs). I think the idea of keeping it somewhere as long as it's outside the house is a good one for a variety of reasons.

 

[ericjeeper]

Most of the innefficiencies come from

The stove not being in the house.Not whether it is gasifier or just an OWB. The Stove if placed in the house you get the radiant heat from it .. Your 10x10 barn won't need a propane heater....You lose some heat in the pipes in the ground.You Just for best performance need to have them located in the building you are heating.
I have an OWB. One of these days I will have an IWB.

 

[gregoryinns]

One thing I noticed while I was living with my parents: the modern wood gasifier they had (I believe it was a Tarm, but I don't remember the model) was well insulated and gave off very little convection heat. That was somewhat of a "bummer" because the wood stove that it replaced was a simple steel box with 10-20 gallon water jacket on top and there were some advantages to that.

My goal is to design a system that I can let sit if I can't run it (like becoming ill, going on vacation, etc.) So, if there is a way (and a previous response indicated the possibility) of having my indoor furnace (in my case, Buderus oil furnace) circulate hot water to the boiler sitting in an unheated outdoor building, I might be able to avoid the extra cost of "freeze protection."

I do not want to be a slave to my wood furnace, whatever the solution is, and I realize there may be an extra cost associated with that.

 

[oneoldbanjo]

I just looked at the Garn website and they have a video.

http://garn.com/content/Movie.aspx

The furnace appears to burn very clean and it is nice to be able to open the door and not get a blast of smoke out the door.

It appears that you might actually be more of a slave to this type of furnace. According to the video the burn lasted a couple of hours and will heat the home for 24 hours on the stored heat without any additional burning. It might be possible just to start a fire in the morning and another at night and not have to tend the fire by adding wood until the temperature is reached. I don't know what kind of safeguards they have to prevent the water getting too hot in case you put in too much wood.

I originally looked at the Garn before I bought my Woodmaster. The Garn was more expensive and didn't have any local dealers and there would have been a significant frieght cost in addition to the purchase price - plus it would have been necessary for me to install the furnace in my garage instead of outside and I really couldn't spare the room. Our heating season is actually pretty short in Northen Kentucky and the OWB sits dormant longer than it is in use......I couldn't justify the extra expense and loss of garage space for the Garn even though it was cleaner burning and more efficient. I don't imagine that it will be too far in the future before someone combines the technology of the Garn into a unit that is mounted outside like a conventional OWB.

 

[cabinman]

antifreeze

One thing I noticed while I was living with my parents: the modern wood gasifier they had (I believe it was a Tarm, but I don't remember the model) was well insulated and gave off very little convection heat. That was somewhat of a "bummer" because the wood stove that it replaced was a simple steel box with 10-20 gallon water jacket on top and there were some advantages to that.

My goal is to design a system that I can let sit if I can't run it (like becoming ill, going on vacation, etc.) So, if there is a way (and a previous response indicated the possibility) of having my indoor furnace (in my case, Buderus oil furnace) circulate hot water to the boiler sitting in an unheated outdoor building, I might be able to avoid the extra cost of "freeze protection."

I do not want to be a slave to my wood furnace, whatever the solution is, and I realize there may be an extra cost associated with that.

Whats wrong with using a antifreeze mix? Eric

 

[iCreek]

perfect for me ..

but I don't think it's the perfect solution.

Depends on the situation, for me it was a perfect solution...

low cost, got a used Hardy OWB from a family member that upgraded.

backup system is my existing propane furnace set at 65, owb set at 73

other benefits like some others stated: no close neighbors, (all family), no bugs, dirt, smoke in the house (big plus for pleasing spouse), free wood on the farm, (it would just rot away if we did not keep up with downed and standing dead trees), great exercise in the fall and winter.

I just can't believe it's a lot more than what these guys are paying for their OWBs.

I have about $800.00 in my complete setup.

 

[Coldfront]

I know insurance co's don't like them, but I love my inside wood/gas furance. It will heat my house even if the power is out for days. Of course I do have a basement that would be a big factor. Heat continually comes up from the vents even when the blower is not running. I can control the temperature of my house just by the kind of wood I am burning. Bugs have never been a problem, they usually abandon the wood when you split it and start throwing it around. I never notice smoke smell in my house. The dirt in the basement is easily swept up and thrown into the ash can. Best of all I can sit and watch the fire with a beer in hand on cold winter nights.

 

[mtfallsmikey]

Propylene glycol antifreeze is $$$$!!!! Around $10/gaal. here, 50/50 mix for an OWB with a couple hundred gal. storage would be costly to do.

 

[Butch(OH)]

While I will agree that the OWB is not a perfect solution, it is one that works well in certain situations. Like any other form of heat an OWB is an easy target to pick apart when people apply a "fix all" title to them. I have personally counseled more people away from an OWB than towards one.

If a person has unlimited fuel resources. If he would rather be in the woods then in the mall. If he uses lots of BTUs. If he doesn't mind spending time "minding the fire". If he doesn't mind spending half a day in the spring "putting it to bed". And if he doesn't have to charge it all on a VISA card. Then he should consider an OWB.

If not,, then the charges against them such as too much money, wood waster, time consuming etc become valid reasons not to own one.

 

[oneoldbanjo]

I agree with Butch - an OWB is not a cure-all for energy costs and they do not work in all situations. For me it works great and will save me a great deal of money over the years. I installed a forced air AC/Heat pump system in my house and I use it in the summer for cooling. I also installed an air/air heat exchanger in the house ductwork for the OWB, a heat exchanger for my water heater, and in my 40' x 45' garage I installed the hydronic heating in the concrete floor. My plan was to just use the heat pump until the weather dropped below 40 degrees and then fire up the woodburner - but I actually have been putting a small fire in it as soon as the house needs heat.

For me the OWB made sense as I was able to avoid having to install a second heating system in my garage, I get hot water, and I keep my house warm with the trees that get old and fall down. It probably isn't a lot of extra work as I would have to cut up the trees anyhow to keep the woods and pastures cleared. I have never heated this new house and the garage with anything but the OWB in cold weather so I can't really compare savings. I have talked to my neighbors and my winter utility bills of $ 70 a month for my 2,200 square foot house and 1,800 square foot garage seem small to their $ 300 - $ 600 a month bills. I also never feel guilty when I get cold and crank the thermostat up a bit - as it only requires another log on the fire and doesn't affect my wallet.

If you have neighbors with a couple hundred feet - I certainly don't think that a conventional OWB is appropriate and you may need to find a clean burning OWB or gassifier.

Also for me the issue of freezing or maintenance while I am away is not an issue. I live in a rural farming area and I have two neighbors with indentical OWB units and we all are willing to watch each others OWB while the neighbors are away. Also if my fire goes out and the weather is cold the furnace inside the house will keep the circulating water warm and keep the OWB from freezing - however it will be my Heat Pump that is providing the heat. Last Thanksgiving I loaded up our OWB as full as I could get it and turned the house thermostat down to 60 when we left on Thursday morning. The temperature was in the 20's at night and the 40's in the day and when we got back Sunday night the fire was still going and I didn't add any more wood until Monday morning, which was 4 days of heat from one loading!