Do I want a wood boiler?

[Ruger]

Hi guys, I just moved into my first house, it's a 1,000 sq foot ranch with a full basement. I decided I wanted a woodstove mainly to reduce my oil usage and to have a heat source during a prolonged power outage. Right now I'm running an inefficient oil boiler with hot water baseboards and no hot water storage tank or water heater and it burns through oil like mad. I went out and looked at a few new wood stoves. I had it narrowed down to the largest qudrafire (forget the specific model) or Jotul TL50 when I spotted a Harman wood/ coal burner across the showroom (sf160). That thing opened a whole new can of worms for me and now I'm overwhelmed with all the possibilities. I'm hoping there are a few people here who have learned a few lessons over the years regarding wood stoves/boilers and can head me in the right direction. I have a limited budget of about 6k to work with for now and want to do what I can with it. My budget may not allow for it right now but eventually I would like a system that allows me to:

1.) use wood as the primary fuel source. (coal is ok as a secondary or supplemental fuel)
2.) provide all domestic hot water and if possible eliminate oil usage entirely
3.) not be reliant on electricity (ok supplementally or for convenience features but not dependent upon to function).
4.) be capable of heating the entire house and basement.

Is doing something such as incorporating the Harman boiler into my current oil boiler system a realistic option or should I just settle for the lower heating costs and simplicity of a good wood stove and hold off on any more "integrated" ideas like the wood boilers for now? Also any other ideas are welcome if I'm headed in the wrong direction already.

Thanks

 

[Boil&Toil]

It is difficult to near-impossible to have a boiler system that is fully functional (or even nearly so) when the power is out. Too many pumps, etc. required to move the heat around. For that case, a simple woodstove in the lowest level of the home that has a surface you can heat a pot or kettle of water on is hard to beat, function and reliability wise. Won't heat the whole house well, but it will keep it from freezing (well, most houses) and let you eat.

My "only partially implemented plans" for dealing with serious power outages (and having boiler systems and other electric things, in small amounts anyway, work) are to have a low-speed (reliable, quieter) diesel generator with liquid cooling, said liquid cooling being dumped into the heat storage, and also electric elements available if other loads are not providing sufficient load (diesels don't really like not working at least 25% load or so.) But there's also a simple woodstove...complicated systems can break down.

$4K for "not a gasifier" is probably not going to fly with most of the boiler-heads here. You can get a used creosote-factory for under $1000 with a little patience on craigslist, and from what I can see in the vague literature, it won't be any more of a creosote factory than this is likely to be. Gasifiers are far more popular here precisely becasue they burn pretty much all the stuff that will form creosote before sending it up the chimney, and many owners have had a "smoke dragon" and the associated chimney fires (or at least need for extensive cleanings) before they got a gasifier.

Another possible option that should fit your budget would be to replace your oil boiler with a full-on pellet boiler, if your oil boiler is, indeed, inefficient. Set up appropriately, they are a "fully automated source of heat" and so far the $/BTU delivered is staying well below oil...

 

[Woodfarmer1]

I ran my boiler for three days before Christmas when our power was out with a portable 3000w Honda generator

 

[NE WOOD BURNER]

You could look into FHA wood furnace. several can be run in the event of a power outage.

 

[peakbagger]

It would be hard to justify a wood boiler for a small house. Ten to fifteen thousand bucks will buy a real nice wood stove and several year of wood. The least cost way to run a boiler with the power out is generator. Sure you can put in battery bank but for the rare times you will need it hard to beat a generator. I have wood stove that can be switched in place of the boiler and when I lost power many years ago for en extended period the wood stove was fine.

 

[Ruger]

I have no idea if it would work in practice, but in theory, wouldn't it be possible to just install additional bypass piping to exclude the circulator pumps, etc and allow the system to simply operate on one open loop where the heated water rises to the upstairs and upon cooling, returns to the boiler in a continuous cycle? I have seen this work on a small scale and if I understand correctly, don't some of the old cast iron systems work in a similar manner?

 

[Boil&Toil]

Theory and practice are the same in theory, but different in practice. That works better in theory than in practice, and it works better in practice if it's designed from the ground up to work that way. You don't need a bypass - circulator pumps are non-blocking. You may need larger diameter pipes than a pumped system needs. Long horizontal runs (you did say "ranch") are not too friendly to having it actually work - last one I worked with was a single baseboard loop around the floor - hard to get much gravity flow on that. If you spend to change over to a lot of tall wall radiators that can be top fed and bottom drained in short segments, mayyyyybe. How often does the power go out, and for how long, where you are at? Here's one example of tall radiators...

(broken image removed)
I'd say the answer to your question is invest in a good, clean-burning wood stove and a proper chimney for it - and perhaps some insulation, depending on the state of your basement/rest of the house. You definitely can heat (to the point of not freezing, anyway) a one-story ranch house of moderate size with a wood stove in the basement...and it's a lot less cost than a decent boiler, or even a bad boiler.

 

[rowerwet]

For the money any woodstove will beat a wood boiler in simplicity and cost to buy. The boiler will get heat to every room the same way oil heat does, the wood stove will need fans in doorways to get the ends of the house close to comfortable in a ranch.
Unless you live where power failure is comon the times you will run on a generator will be few enough that the boiler could be a good option.

 

[STIHLY DAN]

Save the cash. get 2 wood stoves one in the basement 1 in living area. Then get a hp water heater. No oil easy heat and cheap hot H20.

 

[Ruger]

I see what you guys mean. Sounds like it would be a lot of money for an at best moderately effective setup. It has some novelty to it but I don't have the time or money to mess with that. If I would go with the boiler I guess a small generator would be the ticket. I'm about an hour north of Philly near Allentown PA and we don't really have more than 3-4 outages a year, however, the last 3 years we have had some freak storms like Sandy and I believe the year before that a rare October snowstorm that occurred while the trees still had leaves and brought down thousands of huge trees, many onto power lines. Both caused 7-10 day outages. Other storms 1-2 days.

My house was built in the 50's and is brick with a full concrete unfinished basement and uninsulated walls but is still pretty well sealed with new windows and doors. Because the house is only 1,000 sq ft excluding the basement, I think a good size stove like the Jotul 50TL at 83,000 max BTUs should be plenty if I put it dead center in the basement near the steps and run a six inch double walled pipe straight up through the roof. The heat coming up through the doorway and through the floor should add a good amount of warmth to the upstairs. Maybe then it would just be a matter of cutting a couple of vents into the floor of the far rooms?

 

[Boil&Toil]

Yep. Kept a 24x36 full-basement ranch thawed with a woodstove in the center of the basement during at least one 3-day winter outage. Both the "hot air up the stairs" and the radiant floor heat (from hot air in the basement) work. I don't know that floor vents are OK with current fire codes (I suspect they are not, but it's not an area I've looked at too closely.) If attached to a hot air furnace, they are, but as simple openings between floors, I think they are not.

 

[STIHLY DAN]

If you go that route. I would highly suggest that you insulate the basement walls. You will have an 80* basement and the concrete is a huge heat sink.

 

[Ruger]

Yea I might consider some thin insulation, maybe that foam board or something. I don't have any experience with heating a concrete area but part of me wants to see what this stove will do first. From what I hear, the new Jotul stoves are really impressive and I'm afraid that I will cook myself out of the basement where I have a workshop and laundry room. My basement seems to hold heat surprisingly well. I had two 1500 watt space heaters down there at one point and they actually raised the temp quite a bit. I wish I would have used a thermometer. Its bone dry and well sealed for an older house. Maybe I'm being overly optimistic though haha.

 

[Vizsla]

Are the older non gassing Tarms really a creosote problem? Iam sure they can be made to be bad. But the ones I seen in cheboygan and traverse city were either well used, just cleaned up or I missed something. Only one had storage and did batch burns.

 

[Chicken Farmer]

I live in rural midwestern Ohio. It is not uncommon for us to loose power occasionally during the winter. I had an old boiler system in the house when I bought it about 10yrs ago. The house was built in 1900. The boiler was a gravity feed system with a wood box that was installed in the house in the 1920's. Some time during it's life, somebody converted it to a propane burner. It kept the house warm but would drain a 500 gal propane tank in about 6-7 weeks - ouch. I tore the whole system out, radiators and all. I put in a wood forced air furnace with driving idea that it had to heat in a power outage. The furnance (check signature) I chose is a non-gasser and does not not have secondary burn and makes a fair bit of creosote. I will tell you that the Charmaster will definitely keep the house warm, but you have to keep an eye on the chimney and the flue temps. I am in the process of designing a radiant floor system and will probably go with a Garn Jr. It will run on a small Honda generator indefinitely. Since I already have a new class A stainless chimney, I will re-purpose it for a small wood stove for use in an extreme outage or to boost the romantic mood.

I guess my advice to someone who is in the same spot I was two yrs ago, don't get hung up on the "heat during power outage" thing like I did. If you choose a good wood stove with secondary burn, you're killing two birds with one stone, no power needed for normal operation and heat during outage. If you choose the boiler system, you are gaining huge efficiency over the oil boiler and can still run it on a small-ish generator.

I started a thread awhile back to talk about wood furnaces and what drove my decision, you can read it here:

https://www.hearth.com/talk/threads/charmaster-chalet-anybody-running-one.121921/#post-1637589

Good luck!!

 

[bpirger]

Don't skimp on your chimney. When you say double wall, hopefully you mean the insulated double wall stainless steel stuff. You'll know when you go pay for it....is it $30 a foot these days? Make sure the install allows you to inspect it inside some "chase" that encloses it, or have it in the back of a closet (protected) or whatever. Double wall, non-insulated, is not what you want. Your chimney may cost more than your woodstove. Never ever heard of a house fire caused by the woodstove falling apart....have heard of the chimney fires starting a fire....almost everytime it is wood burning related.

 

[Boil&Toil]

Are the older non gassing Tarms really a creosote problem? Iam sure they can be made to be bad. But the ones I seen in cheboygan and traverse city were either well used, just cleaned up or I missed something.

Firebox has direct (steel plate) contact with waterjacket - so firebox walls/floor/ceiling never get above 200F - so you get creosote and incomplete burns. Does seem to burn through cast iron grates quite nicely though, based on what was with it when my brother retired it for a gasifier. I am quite seriously toying with gasificating mine (the intact one my brother retired - uploaded a new profile pic of the other one) and part of that will be to insulate the firebox to some extent. Obvious downside is that the heat exchanger is not up to snuff with modern gasifiers...if part A works, that will be part B; or I'll get some common sense and use the wallet crowbar instead. Naaah...

 

[Chicken Farmer]

Don't skimp on your chimney. When you say double wall, hopefully you mean the insulated double wall stainless steel stuff. You'll know when you go pay for it....is it $30 a foot these days? Make sure the install allows you to inspect it inside some "chase" that encloses it, or have it in the back of a closet (protected) or whatever. Double wall, non-insulated, is not what you want. Your chimney may cost more than your woodstove. Never ever heard of a house fire caused by the woodstove falling apart....have heard of the chimney fires starting a fire....almost everytime it is wood burning related.

+100

 

[Ruger]

Don't skimp on your chimney. When you say double wall, hopefully you mean the insulated double wall stainless steel stuff. You'll know when you go pay for it....is it $30 a foot these days? Make sure the install allows you to inspect it inside some "chase" that encloses it, or have it in the back of a closet (protected) or whatever. Double wall, non-insulated, is not what you want. Your chimney may cost more than your woodstove. Never ever heard of a house fire caused by the woodstove falling apart....have heard of the chimney fires starting a fire....almost everytime it is wood burning related.

Yea I believe double wall insulated was what I was looking at. I am going to close off the end of a closet and run it up through there. Each three foot section was a hundred bucks at Tractor Supply if i remember correctly. I will buy the best i can find tho if there is a difference in quality between brands. i know they carry some chinese junk at times so ill have to do my research first. Hopefully the fact that I will have a good 15 feet of chimney inside the house will help prevent creosote issues too but i wouldn't know.

 

[Chris Hoskin]

Ruger, based on 1000 square feet, your heating load is probably something on the order of around 30,000 btu/hr on the coldest day of the year. You will not be well served with a big wood stove - same as with a wood boiler that is too big - lots of damped down, smoldering burning, over heating of your basement and creosote in your chimney. What ever you get, size it closer to your load (a little under-sized is better than a little over-sized). If you really do want a boiler, you may want to consider the small Walltherm that Marc Calluwe sells. Used with a 200 or 300 gallon tank this would be a great solution for your small heating load and not cost as much as a "full sized" 100,000 btu/hr+ traditional gasification boiler.

 

[Ruger]

Ruger, based on 1000 square feet, your heating load is probably something on the order of around 30,000 btu/hr on the coldest day of the year. You will not be well served with a big wood stove - same as with a wood boiler that is too big - lots of damped down, smoldering burning, over heating of your basement and creosote in your chimney. What ever you get, size it closer to your load (a little under-sized is better than a little over-sized). If you really do want a boiler, you may want to consider the small Walltherm that Marc Calluwe sells. Used with a 200 or 300 gallon tank this would be a great solution for your small heating load and not cost as much as a "full sized" 100,000 btu/hr+ traditional gasification boiler.

Yea what you are saying is a concern i suppose. It is tough to determine what is the right size and it could be expensive to get it wrong! The problem is conflicting goals. I am looking for long burn times that come with larger stoves but dont need the BTU output. I plan to put the unit in the basement so i would imagine that would require a little larger stove but maybe 70-80k BTUs is extreme. I came across those Walltherm units and thought that was really neat but figured it was something hard to obtain here in the US and had never heard of them before. There again though, they are only claiming a 4 hour burn time and i wont be home/awake to keep it going. I suppose there is just no getting around the shorter burn times of a smaller stove...

Now keeping in mind that I have limited experience with woodstoves, i'm goin to ask what will probably be a dumb question: If i go a little to big, would it be possible to just crack a basement window and allow some of the heat to escape or am i going to create drafty conditions or other issues? This is one of those questions i think i know the answer to but need to hear someone say it haha

 

[Boil&Toil]

Point being the 2-300 gallon tank means you don't HAVE to keep it burning all the time, but it still heats your house.

As for the heat load, given the age of your house, I'd look at current oil consumption first and foremost to try and narrow that down a bit; but you are also talking about heating the basement (which you mostly don't now, I gather) so you may be looking at more like 2000 square feet, as it's "full basement." Most oil companies will provide an average (outside) temperature along with the bill, which can help in figuring what your current use in terms of BTU/Hr/DegF is, so you can plug that into the design temperature (lowest exterior you expect to see and stay at "normal" temperature inside) to get a value for BTU/Hr based on something other than pure guesswork.

 

[Ruger]

Point being the 2-300 gallon tank means you don't HAVE to keep it burning all the time, but it still heats your house.

As for the heat load, given the age of your house, I'd look at current oil consumption first and foremost to try and narrow that down a bit; but you are also talking about heating the basement (which you mostly don't now, I gather) so you may be looking at more like 2000 square feet, as it's "full basement." Most oil companies will provide an average (outside) temperature along with the bill, which can help in figuring what your current use in terms of BTU/Hr/DegF is, so you can plug that into the design temperature (lowest exterior you expect to see and stay at "normal" temperature inside) to get a value for BTU/Hr based on something other than pure guesswork.

This is true! I can't believe i wasn't thinking that way. It really will be the equivalent of a 2,000 sq ft house because i would like to heat the downstairs. Unfortunately my oil company supplies me with a carbon paper BOL and thats about it. Also, I would have to take their figures with a grain of salt anyway given what i believe is inefficient functioning of my furnace. Its interesting how opinions seem to range from "insulate the basement" to "get a much smaller stove" haha I am certainly not qualified to have an opinion yet but i am leaning toward the belief that the 80k BTU stove may end up being a little large. I think that will most likely be true in regards to the basement though. My gut feeling is that a large stove would be fine if i had proper heat distribution to the upstairs. Im envisioning a sauna basement and somewhat cool upstairs but thats some poorly informed speculation right there!! If the truth lies somewhere in the in between and what those like StihlyDan are suggesting regarding heat loss to the concrete, maybe that would keep the basement temp in check....

 

[Boil&Toil]

Check that carbon paper - it's often on there; or the bill if they bill you for the delivery. If you keep your oil bills for date and fill amount you can (more tediously) look up the climate data from the nearest weather station (airport, usually) when it's posted by the NWS. Even if you you don't like the boiler (and those can be upgraded, too) it's a real number that says something about the actual heat load of your house, rather than being a guess.

 

[Rory]

Back when my house was a 1000 sq. ft. ranch we heated it beautifully with a woodstove in the basement. My father helped me build a plenum over it and we ran 3 ducts and put a large cold air return in the far corner of the house. With just a passive air flow the duct under the towel rack in the bathroom lifted the towels. The only downside was the lack of any filtering that you would have in a forced air system. I also added a water coil and got most of my hot water in the winter from that. Four cords of wood a year did wonders.