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One wood/oil combo boiler or two stand alone units?

  • Wood/oil combo

    Votes: 0 0.0%
  • Two stand alone units

    Votes: 7 100.0%

  • Total voters
    7
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Stihlms391

New Member
Feb 16, 2016
1
Indiana
Let me start by saying this is my first post on hearth.com, but I am no stranger to this site. You all are full of knowledge and have answered a lot of my previous wood burning questions. However, I have not been able to find much information on my particular situation.
I recently purchased a new home that was built in the 1920's it's a two story with around 3000 square feet. It's an extremely well built home with a lot of windows. It has an old fuel oil boiler in the basement with radiators upstairs. The oil boiler still works but is very old and inefficient. I am wanting to install a new boiler to replace the current one. I am pretty much set on the wood gasification units however my question is.....
Do I purchase one dual fuel/combo unit that is wood with an oil backup? Or do I purchase two stand alone boilers? One being a wood gasifier that would be the main heat source with a separate oil backup boiler. The chimney does have two flues so having two stand alone boilers should not be a problem except I wouldn't know where to start with plumbing them both up. I would think buying one quality duel fuel boiler would be much cheaper than buying two stand alone units.

Is there such a thing as an efficient duel fuel/combo boiler that does well at burning both fuels? I have found conflicting information regarding this.
- If so what brands should I be looking at? Currently the only combo units I've been looking at are the AHS wood gun and the new horizons biomass combo.

To me it only makes since to have one unit that burns both fuels. I understand that some of you will say to buy two stand alone units that way "all your eggs aren't in one basket" if the boiler sprung a leak, etc.. But to me the ease and convenience of having one boiler that burns both fuels far outweighs the negatives. The only way I'd consider two stand alone boilers is if there isn't a wood/oil boiler out there worth a crap. Also if I were to go with the two stand alone route I would buy a new wood gasification boiler and use the old fuel boiler as a backup for the time being. (Two boilers aren't in the budget right now)
But I'm fairly new to boilers and that is why I'm asking for your advice. My old home was a smaller ranch style and it had a Vermont Castings Defiant Cat stove and what a stove that was!

Looking forward to your advice!
 
I wish I could remember which dual fuel I was looking at a few years back... it's no help without a brand, but had great reviews.
I had to do an insert instead due to the cost of the boiler ($7k+ for unit plus piping ). I like the idea of an all in one boiler, but I am now kicking around thoughts of an add on unit to my existing boiler. In he event one does fail it could always be isolated/repaired w/o loss of heat due to down time.
 
Depending on your level of commitment to heating with wood you could potentially almost never use your oil boiler. I have an indoor gasification boiler with storage and I have not used my propane boiler for heat at all this entire winter. I have learned a lot since I had my system installed, some here and some by Googling things like low temperature heating. My advice would be to do a little reading about low temperature emitters and how the world of heating is moving in that direction. Assuming you are going to stay in the house for a gong time (I am assuming you will since you are investing in a gasifier) thinking about where heating systems are heading and deciding if you want to go that way might be worth some thought. If you see yourself heading in that direction you may want to consider boilers that have built in technology to accoodate it. You an certainly achieve the same thing by installing individual components but that will add cost and complexity. Here is a link to a good PDF on the subject, there is a YouTube presentation by the same person on the same topic but for some reason I wasn't able to locate it. http://www.duluthenergydesign.com/C...aterials/2013/Day1/hydronics-siegenthaler.pdf
 
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Depending on your level of commitment to heating with wood you could potentially almost never use your oil boiler. I have an indoor gasification boiler with storage and I have not used my propane boiler for heat at all this entire winter. I have learned a lot since I had my system installed, some here and some by Googling things like low temperature heating. My advice would be to do a little reading about low temperature emitters and how the world of heating is moving in that direction. Assuming you are going to stay in the house for a gong time (I am assuming you will since you are investing in a gasifier) thinking about where heating systems are heading and deciding if you want to go that way might be worth some thought. If you see yourself heading in that direction you may want to consider boilers that have built in technology to accoodate it. You an certainly achieve the same thing by installing individual components but that will add cost and complexity. Here is a link to a good PDF on the subject, there is a YouTube presentation by the same person on the same topic but for some reason I wasn't able to locate it. http://www.duluthenergydesign.com/C...aterials/2013/Day1/hydronics-siegenthaler.pdf
Hi 391, Check out pologuy. He lives close by ct, installed a woodmaster combo unit.
 
391, right about now, you're where I was 21 years ago - Back then, there were only a couple of wood/oil combo boilers. One was huge, way too big for our house at the time. The other took 16" wood, which I didn't want to mess with. Lots of combo hot air, very few boilers. I went with a Harman add on, and it pretty much worked flawlessly for 16 years except for..........massive creosote issues. The Harman had an auto damper door, when the water hit 180, the door closed, when it cooled to 150, it opened again. We use good dry wood, but this type of cycling hot/cold chimney is a disaster waiting to happen. I have the un-official record here for the most unreported, un responded to chimney fires. Some were scary. 5 pounds of salt dumped down from the top is the best extinguisher I ever used. Deep snow on the roof, no problem. Icy, well thats another story. If the Harman had burned to storage, [I knew nothing about storage back then], I don't believe I would have had a problem. Probably could have been hooked up that way, I just didn't know. Can a combo unit burn to storage? I don't know - The Harman only had about 30 gal of water in it. The flue here still has creosote in it, 3 winters after the Harman went to the scrap yard. It loosens up and I scoop it out. Nothing in it now but the oil boiler. The Garn [best investment in a long long time] is out in a separate shed, no chimney cleaning needed. I think separate units is the way to go, an oil boiler is designed to work with oil, a wood one with wood. Combining the two, you're going to loose somewhere.
 
Let me start by saying this is my first post on hearth.com, but I am no stranger to this site. You all are full of knowledge and have answered a lot of my previous wood burning questions. However, I have not been able to find much information on my particular situation.
I recently purchased a new home that was built in the 1920's it's a two story with around 3000 square feet. It's an extremely well built home with a lot of windows. It has an old fuel oil boiler in the basement with radiators upstairs. The oil boiler still works but is very old and inefficient. I am wanting to install a new boiler to replace the current one. I am pretty much set on the wood gasification units however my question is.....
Do I purchase one dual fuel/combo unit that is wood with an oil backup? Or do I purchase two stand alone boilers? One being a wood gasifier that would be the main heat source with a separate oil backup boiler. The chimney does have two flues so having two stand alone boilers should not be a problem except I wouldn't know where to start with plumbing them both up. I would think buying one quality duel fuel boiler would be much cheaper than buying two stand alone units.

Is there such a thing as an efficient duel fuel/combo boiler that does well at burning both fuels? I have found conflicting information regarding this.
- If so what brands should I be looking at? Currently the only combo units I've been looking at are the AHS wood gun and the new horizons biomass combo.

To me it only makes since to have one unit that burns both fuels. I understand that some of you will say to buy two stand alone units that way "all your eggs aren't in one basket" if the boiler sprung a leak, etc.. But to me the ease and convenience of having one boiler that burns both fuels far outweighs the negatives. The only way I'd consider two stand alone boilers is if there isn't a wood/oil boiler out there worth a crap. Also if I were to go with the two stand alone route I would buy a new wood gasification boiler and use the old fuel boiler as a backup for the time being. (Two boilers aren't in the budget right now)
But I'm fairly new to boilers and that is why I'm asking for your advice. My old home was a smaller ranch style and it had a Vermont Castings Defiant Cat stove and what a stove that was!

Looking forward to your advice!

Couple of basic starter questions.

If you got something wood burning in place, how much do you think you would need to use the other backup fuel source? Quite often, or rarely? With us it's only maybe 2 days per winter.

And, do you have other fuel cources available? Like propane or NG?

And another - how do you heat your domestic hot water?
 
Hi 391, Check out pologuy. He lives close by ct, installed a woodmaster combo unit.
Hi I've been busy this year. I also started installing low temp radiators. They are great. Back to the FlexFuel. One word..........PHENOMENAL! Its been everything i've imagined. Im not a techie. I love the interface. It reads my tank temps, I can have it start manually just by keeping it loaded. I set it to come on when the tanks go below a certain temp or a certain time. It cleans itself. I only clean the ashes per manufactures recommendations. My wife uses it easily when i'm not home. It doesn't burn much wood. I did buy the pellet setup. I haven't had the chance to use it. Its a simple change over. You change a small grate like a grill grate and put on a small chute to guide the pellets in. Honestly it takes 2-3 minutes to change over. The price of oil didn't lead me to pellets this year. Last year it worked well. This year i wasn't so eager to burn wood due to oil pricing. I did use the boiler but not much. Next year i'm going all out. This machine is a beast. I also love the fact i can load more wood and avoiding any smoke in the house by pressing a button. A fan comes on and sucks the smoke out. Tons of safety features. Permit passed with no problems. Great machine. Everyone here is somewhat biased. We all know what we use. I love mine, others love theirs. Best thing to do is read, read, read. What drove me to this machine is at the time it had the highest EPA rating, UL listed, made in the US, burns cord wood and pellets, changinging over very simple, auto igniter, on board screen technology that monitors flue temps, tank temps, return temp, air factors, and much more i haven't learned how to use yet. Great customer service. I talked to them for two years before buying the unit. you have to do yor homework and stand behind your decision. If I had to do it over I would have purchased the unit much sooner, lol.
 
I've the same question about how often you are planning to utilize the fuel oil to heat your home and DHW? I haven't used our propane furnace at all since installing our wood boiler except once during a power outage. Your boiler still functions, so it could be like you mentioned, your backup heat source and you could put your resources into a higher quality wood boiler. If you need to use oil with some frequency that would be a different situation.

Mike
 
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