BioPellet said:
Thanks to Be Green for his continued reality check and I say reality becuase he has actually taken the time to burn my product rather than worry about what might happen if you do
I burned compressed sawdust logs from several different major manufacturers in two stoves. One was a Defiant Catalytic and the other is a Hearthstone Mansfield non-Catalytic (current stove). I am now a fourth year 24/7 fall/winter/spring wood burner so although I'm not a seasoned vet, I'm no longer a novice.
Now, I have burned a couple tons of the things when I was low on wood or just wanted to try something new. These products are not BioBricks, but out in my area "Atlas" makes the brick version of the compressed sawdust wood and they look identical in composition to the compressed sawdust logs, except they are the size of bricks instead of 4-6" diameter X 12-16" "logs". I haven't burned the Atlas bricks (they were new last year), but will try some this winter just so I can put this story to rest one way or another.
My observations:
1) They burn either really hot or they smolder. The temperature control in my Defiant couldn't regulate the temperature of them correctly. The stove was either running near over fire condition when it was set on medium to high or the catalytic element was running orange hot for hours on end when set on low because of all the smoke the things created. You had two temperature controls: Surface of the sun hot or smolder. There was no in-between. Mind you this was with the thermostatic damper control of the Defiant. It clearly was not calibrated to burn the compressed sawdust products.
2) Same for my soapstone stove. My Hearthstone will run very hot with them or smolder. If I have the damper on anything other than the lowest setting the stove will approach over fire temperature quickly if I have more than three of the things in the fire box. If I set it on low then the fire is lazy and smolders creating a lot of smoke and a dirty burn.
3) Did I mention they burn incredibly hot? I put four of the logs in my Mansfield by mistake one night. The stove was hotter than the Space Shuttle rocket boosters. I really didn't think I could get it to cool off and was going to over fire. That was on the low setting. I had to stay up to watch the stove through the burn cycle to make sure it wasn't going to get into a bad condition. I'd hate to think what would have happened if I loaded the firebox up with the things.
4) The unburned gasses suddenly combust and cause mini-explosions in my stoves. Because the logs burn so hot you are forced to choke down the air. During the end of the burn cycle the logs create a lot of smoke and this smoke ignites suddenly. In my Defiant it blew smoke out of all the door gaskets into the room with a sudden whoosh. This is normally corrected by adding a little more air to the burn, but again the Defiant thermostatic damper never did this with cord wood. The Mansfield does the explosions as well, but not as spectacularly. However the Mansfield does not have an automatic damper and you're forced to either run the stove on the lowest setting, or give it more air and risk over firing the stove if you have too many logs in it.
5) They leave a bad coal bed to restart the fire. Yes, they burn with little ash, but they also burn with little coals. It's a major pain to restart the fire because you don't have a nice bed of coals to re-light quickly. Cord wood leaves nice coals and is fast to re-start. I
like having a bed of coals in the stove. It makes adding new fuel much easier and requires far less babysitting between cycles. The charcoal is not wasted by sitting in the stove, it is eventually burned.
6) They don't save you any money. Yes, they claim they have more BTUs than a cord of wood for the price. But I burned them faster than cord wood because of
how they burned. I'd rather have a cord of wood than 1.5 cord BTU in these products any day.
As for BioBricks and how they burn. I don't know specifically because they don't sell them out in my region. But, they do have the Atlas bricks out here and I'll give them a test run this season. I can't see any particular reason why they'd be any different than other compressed wood products though.
My experience is properly seasoned cord wood burns better and safer in wood stoves than these products. Yes, the compressed wood products may be more convenient, but they require more babysitting and figuring out how they will burn in your particular stove. However, there is also the idea that these stoves are designed to be burned with cordwood of a certain moisture content. I'm not a combustion engineer, but it seems that stuffing them full of extra dry and dense fuel it was not intended to burn could lead to unintended, and possibly dangerous, results.
In the end, I stand by my statements above. Burn these products if you want, but I'd watch them very closely to know how they burned in your particular stove. As for me, I prefer properly seasoned cord wood.