Has Anyone Tried Burning BIO Bricks in an older Tarm Boiler?

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defield

New Member
Nov 21, 2008
433
South Central Maine
I have a Tarm add on boiler that we have been using for supplimental heat for about 29 years.

Am getting to the point where the joy of stacking and hauling and restacking firewood is not as mnuch fun as it used to be, and space required is an issue. Partly why we installed a pellet stove . . . . . .

We still plan to use the Tarm during the cold months. Does anyone have information to share about burning BIO Bricks in a Tarm?

Thanks,

The Old Ranger
 
they should burn great. Start with smaller loads to see how it goes - the bio bricks have a lot more energy content than normal cord wood and, I believe, they expand a bit as they burn so you don't want too big a load. I am sure that you will quickly find the load size that lasts through the night but does not over load the firebox. Be sure your Samson draft control is working well too so you do not over fire. Good luck and let us know how it goes.
 
I am planning to buy a few and try them in my Memco once I get burning again. Keep us posted please!
 
I've got a few people testing the biobricks in several applications right now... so far, it seems like you can burn them anywhere that you would normally burn cord wood. Coaling is a little different, and I like to mix them with a little bit of wood if I can for that reason, but it's not absolutely necessary. They work nice in a fireplace too.

cheers
 
I have burned bio bricks in my fireplace insert and my prior wood boiler (Buderous 1980's era). I found that the bio bricks are awesome in the wood stove. IMO they work best when you damper the stove down and they release their gases slowly. In the Buderous wood boiler they seem to burn way to fast. Since that boiler did not have secondary combustion or gasification I found the bio brick burned very quickly and I suspect the gases went up the chimney. So IMO they will be inefficient in an older boiler that does not control secondary air that well... I think using them in a modern efficient boiler might work much better...
 
sparke said:
I have burned bio bricks in my fireplace insert and my prior wood boiler (Buderous 1980's era). I found that the bio bricks are awesome in the wood stove. IMO they work best when you damper the stove down and they release their gases slowly. In the Buderous wood boiler they seem to burn way to fast. Since that boiler did not have secondary combustion or gasification I found the bio brick burned very quickly and I suspect the gases went up the chimney. So IMO they will be inefficient in an older boiler that does not control secondary air that well... I think using them in a modern efficient boiler might work much better...

Biobricks can definitely release their potential energy quickly. You will find that people who claim green wood burns better than dry wood are the people who are using equipment that cannot regulate air flow through the firebox. Generally they say that the dry stuff just burns too fast. So, in essence, what they are doing, is using the water in the firewood to slow the burn, and at the same time reducing efficiency a significant amount.

Obviously, whether or not biobricks make economic sense depends on how much you spend for them and what other forms of fuel cost in your area. If you are running a high end gasifier, it's just like buying pellets for a pellet stove or boiler... and at the other end of the pendulum you probably would not want to buy biobricks to feed an older outdoor woodboiler.

If you are going to burn bricks in a traditional wood stove or fireplace, the key, like any other wood burner, it to keep the smallest but hottest fire possible to meet your demand for heat. I think most folks tend to use too many biobricks at a time not realizing how many btu's they actually store in each brick... to be sure, smoldering a biobrick is just like smoldering wood... you produce a bunch of gas that just goes up and out the chimney unburned. Use them sparingly, and burn them HOT and FAST for the best efficiency.

If burn times are an issue, then expect to lose some efficiency no matter what. The best answer to the burn time issue is a gasifier with thermal storage.

cheers
 
Piker, good points. But back to the OP's question. "How will BioBricks work in his 29 year old TARM?" And I think the answer to that question is that vintage boiler will probably not utilize BioBricks potential energy very well. Guess the best thing to do is to try them and see......
 
sparke said:
Piker, good points. But back to the OP's question. "How will Bio-bricks work in his 29 year old TARM?" And I think the answer to that question is that vintage boiler will probably not utilize Bio-bricks potential energy very well. Guess the best thing to do is to try them and see......

I understand what you are getting at, but I must politely disagree.

The bottom line is that the 29 year old Tarm will not utilize the potential energy of any biomass fuel as efficiently as a modern high end gasification wood boiler will... so whether the boiler is burning chunk wood or biobricks, you're going to use more fuel, the amount of which will be in proportion to the unit's efficiency.

Smoldering is bad for efficiency in any wood burning application, regardless of fuel or boiler/stove. So is over firing because of poor draft controls and extremely dry fuel. If combustion air can be controlled at least moderately well, the biobricks will work very well. Very well indeed. If controlling draft is an issue, then the fuel loads will need to be more closely controlled by the user... loads should be very small and the fire will need to be burned as hot as possible. This will require a little more tending of the fire. If this were the case, then I would suggest maybe burning the bio-brick when you are available to tend the fire, and use chunk wood or a mix of chunk wood and biobricks for overnight or when you are away during the day.

There is no doubt about it... you will pay more money for the biobricks than most firewood. The bricks are marketable because they are much easier to deal with than firewood. They take up less space, bring in zero pests like insects, spiders, etc... so there are other things to consider than just the up front cost of the fuel. We all weigh our options differently when it comes to purchasing biomass... so a one-size-fits-all statement that biobricks are only good in sophisticated gasifiers or that they just don't work well in standard stoves and boilers will not necessarily be true for everyone.

I have yet to speak with anyone who dislikes how the biobricks perform. I HAVE heard people say that they would rather save money and buy firewood or cut their own.

cheers
 
I am interested in this question and burning different types of bio bricks and my Tarm Solo Plus boiler. So what is the ideal size and how could I think about cost per BTU for bricks vrs cord wood.

I wrote a long cost comparison about cord wood vrs claims of "brick" dealers and deleted it before posting. Decided to do some more research in other threads. Short version: hardwood brick people can claim anywhere from 2,300 to 8,800 BTUs per pound of their product.. A few acknowledge it depends upon their wood source. Good old Mark Twain obviously never met a salesman doing an eco cost comparrison when he said "there are lies, damn lies and statistics". :)

As I get older, I am wondering about the long term prospects of the 6-7 cords a year wood routine. But after 4 years, I still like my Tarm. Toying with the idea of 4 tons of bricks next year, but first testing a couple of 20-30 pounds of different products for size and handling. Then there is the cost of BTUs.

Advice and thoughts appreciated. Chris
 
hardwood brick people can claim anywhere from 2,300 to 8,800 BTUs per pound

This doesn't make much sense unless somethings other than wood are in bio bricks. All cellulose at the same moisture content has about the same btu/lb. Pines run a little higher due to the sap/resin, and there are other small variations, but not like the quote. So, do some bio bricks have a non-combustible filler? Others a combustion enhancer? Is this a high heat or low heat rating? What moisture content?

As I get older, I am wondering about the long term prospects of the 6-7 cords a year wood routine. But after 4 years, I still like my Tarm.

I hear you. Soon will be 66. But fortunately only need about 4 cords/yr of aspen/pine to meet our needs with the Tarm Solo Plus. First heating season was 2007-08. Still original refractories. Everything looks good. And the wood felling, bucking, splitting and stacking is helping to keep the "old guy" a little buffer than his two sons! I'll keep cutting wood.
 
Jim, you are as pragmatic as ever. Always look forward to reading your posts. By the way, after the first four days using the chain turbulators you recommended I am pleased as the flue temps have been at a consistent 500-600 DegF. Clean boiler at this point but will see how it continues to go. Posted some pics in an earlier post 'Turbulators'.
 
Jim, you are as pragmatic as ever. Always look forward to reading your posts. By the way, after the first four days using the chain turbulators you recommended I am pleased as the flue temps have been at a consistent 500-600 DegF. Clean boiler at this point but will see how it continues to go. Posted some pics in an earlier post 'Turbulators'.

Good to hear from you, especially on the chain turbulators. I see temps around 420-480F on high burn (pine/aspen), and I shake the chains and brush the tubes about every 10 burns. Temps drop after cleaning, and then gradually rise again.

I also have the draft fan damper adjusted down a fair amount to achieve these temps, else the temps would be higher. Is your draft fan damper wide open?
 
This doesn't make much sense unless somethings other than wood are in bio bricks. All cellulose at the same moisture content has about the same btu/lb. Pines run a little higher due to the sap/resin, and there are other small variations, but not like the quote. So, do some bio bricks have a non-combustible filler? Others a combustion enhancer? Is this a high heat or low heat rating? What moisture content?

Off the subject slightly, I hear you. Soon will be 66. But fortunately only need about 4 cords/yr of aspen/pine to meet our needs with the Tarm Solo Plus. First heating season was 2007-08. Still original refractories. Everything looks good. And the wood felling, bucking, splitting and stacking is helping to keep the "old guy" a little buffer than his two sons! I'll keep cutting wood.

To answer the initial post, brick might work in an old Tarm but they are 2x or more expensive on a BTU basis and can cause issues in non-air tight stoves.

Sort of off the subject, I got a couple of years on Jim. I really took a close look at the http://www.chimneysweeponline.com/howoodbtu.htm wood data and how they calculated things. You are right about the same basic value which is 8660 BTUs per pound, with 0% water and 100% oxygen burn. But if the "dry wood" has 20% water, then you really only have of burnable material of 6928 BTUs.. Also the site (which I Iike) calculates stove efficiency when they say sugar maple has 23.2 MBTUs per cord in their chart or about 6200 BTUs per pound for all wood at 20% moisture. Interestingly a 128 cubic foot cord probably contains 85 cubic feet of wood.

Canawick, with 6.5% moisture, does not have any binders, pressure and heat create the bricks. I did some math. Based upon 6 cords of hard wood I got delivered, I figure the cost per MBTUs is about $10. The price of the Canawick at $310 delivered (but stacked!) is about $20 per MBTUs. The Canawick weighs about 5150 pounds per 85 cubic feet, thus takes up about 40% of the space of a cord of wood. More than you wanted to know. I got obsessed :)

So my math says I can pay somebody $200 a cord to stack firewood and still save money. I was a little disappointed but my wife told me to calculated the cost of propane per MBTU, our backup boiler. Indeed 91k BTUs per gallon at $3.50 is over $38 per MBTUs. Bricks is way cheaper and cord wood has all those priceless health benefits for us old folks :)

I have no idea where the American pressed wood brick people get their "approximately 8,800 BTUs per pound". I think it must have some magic dust in it.
 
Good to hear from you, especially on the chain turbulators. I see temps around 420-480F on high burn (pine/aspen), and I shake the chains and brush the tubes about every 10 burns. Temps drop after cleaning, and then gradually rise again.

I also have the draft fan damper adjusted down a fair amount to achieve these temps, else the temps would be higher. Is your draft fan damper wide open?

Damper throttled back a little from when I was trying to reduce flue temps early on.
 
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