I've been posting a lot in the IS tips and tricks thread but now that I have done a few of these tests and think I have it figured out, I'll post this one in its own thread in case it might be interesting to someone who doesn't follow the other thread. I bought a few tons of Ecobricks last year and have about 1 ton left. Since I no longer have access to the woods I used to cut in (inlaws which are no longer in-law) I have pretty much determined that whatever I can't scrounge for free or cheap I'll make up with Ecobricks. For the price I can get them I am not even going to mess with the local wood market. Plus they pack quite a bunch of BTUs into a stove! I have carefully experimented with smaller loads working up to todays full load of compressed wood bricks. Do not try this at home unless you know what you are doing! With my Ideal Steel stove, I seem to get about double the burn time with the bricks, but I haven't done to many long burn tests with it packed with hardwood. All I have is ash, and mostly cut to the wrong size for my previous stoves and also a bit on the small side. So burn length with cordwood I am unsure of, and will experiment more with that later. So I started the load yesterday at 11:13. It was loaded on very little coal bed and a cool 150F stove. The load. Actually I used 4 complete 6-packs for 24 bricks and about 84 lbs of compressed wood fuel. Partly loaded. 3 rows stacked against the back, 5 bricks each. Then 2 across the front on top of coals. The full load. 2 more across the front on top of the first 2, then another row of 5 even with the front and close (1" or so) to touching the secondary air plate in the back. Pretty much fully loaded. An inch or so of gap on the sides, allows for expansion, and a few inches in the front but not enough for another row. I stuck 3 pieces of kindling in the front just to help it get going. Oh and before I forget here are the thermometer locations I will be referencing: Using a Condar catalyst probe, grill surface thermometer on the center burner (hottest part of the stovetop), and the Woodstock supplied magnetic thermometer on the back corner of the stovetop (kind of average STT). These bricks pack a punch and very dry. In my previous tests the IS wanted to burn a little hotter at minimum air then I wanted so I experimented partly covering the secondary air hole. That did exactly what I wanted. I still would like to try a key damper instead, but until I get one the magnet seems to be working well enough, and I have not noticed any increased smoke at all, visibly she burns perfectly clean. In fact here is a shot at just 16 minutes in with CAT at 700F: And here are the stats, 22 hours into the burn so far... She burned just a tad hotter than I wanted there in the first 12 hours, but I think I'll still get plenty good long burn. My house is not very insulated and drafty so by itself this wouldn't be feasible right now (low in 20's high in 30's) but with my pellet stove running on the old side of my house (it's on its minimum setting of 1) is about perfect. I'm also trying to see what it does with minimal amount of fuss... shut it down in 3 moves at the beginning, and then 2 more at an hour and a half (should have just done those in one). It has been fully closed (first notch) ever since. I'll probably bump up the air once it gets close to 500 CAT but so far the house is warm and I am letting it coast as much as possible. The door is completely covered in black so no photos. I don't want to open it and disturb the load. But from what I can see right now it appears to be around 2/3-3/4 still there, a big section down the front in the middle is gone but sides and back still there.
Love these kinds of tests. Thanks for doing them and sharing your results. I discovered eco bricks several years ago and found that 5 of them in my old leaky Hearthstone made for a very exciting burn! When I found a thread where someone loaded 90 lbs of them into a BK I just started laughing out loud as the thought was frighteningly insane given my experience with these products - never quite understood how much better air control the newer stoves had. Curious to see how long my Fireview could go on a load, but I'm a bit too conservative to do such a test.
I used them a lot last year in my Jotul Rockland. I didn't have a good supply of seasoned wood - just some borderline dead standing ash (EAB) I cut that fall. I separated out the pieces that were 20-25% to burn that winter, and mixed in Ecobricks. I ran some loads up to 12 bricks or so but you really had to be careful to get the Rockland shut down quick or you were looking at an overfire situation. I advise a lot of caution for anyone trying the compressed wood bricks, and start with just a few. On the ash cordwood, my Rockland would go about 8 hrs. Loaded up with bricks, close to 12. So I got about 50% longer burn with them in a stove that could not idle low at all. But they gave out a considerable amount of heat the first 1/3 or so, then not very much toward the end. With the far better air control of the IS I am trying to even that out a bit better. Oh, and I guess they are called Enviro-Bricks now. I have not got any since this name-change I hope they are the same product for the same price. They are made close by here in Ohio so they are perhaps a bit cheaper here than elsewhere.
Very interesting. This is my second season using the ecobricks in my old Sierra wood stove. Really gives me a good perspective on the size difference between our stoves, I can just fit 12 bricks, 2 packs, in mine. Five bricks loaded on top of coals will get me through an eight hour night with easy light off in the morning. I have burned as many as eight at a time with no trouble controlling temperature.
Just hit the 34 hour mark and still looking good. Should burn through till the morning I hope. It was tapering off though, which worked fine for the bright sunny mild afternoon we were having. But with nightfall approaching I decided to bump it up. She wasn't throwing out a ton of heat, but still keeping that side of the house a degree or two above what I really needed so no complaints here. But wanted to get it up a tad for night... at 30 hours I bumped up the air 1 notch. Temps still slid a bit. 30 minutes later I went another notch. Temps picked up a little but within about 30 more minutes they started to decline slightly. I wanted to see if I could get it up a good 100F hotter or so, so at about 31 hours into the burn I decided to open the door, snap a pic, and stir up the fuel a bit. First time opening the door, 31 hours in. The back row is still just about full sized. I toppled the stack, poked it a little, closed the door and turned the air up a bit more. Now on notch 5. In one hour on notch 5 the CAT went from 575-750 and center burner 295-345. Here is the graph updated for 34 hours:
Its still alive... barely. Here is a pic when I work up around 6 am... 42 hours and 40 minutes I stirred it up again and opened the air a couple notches. Some of those bricks on the bottom were quite solid still! At 300F on the center burner right now. I won't let it get to the point of needing paper or tinder, but going to try for 48 hrs... I'll have a couple more pics and data shortly.
Just reloaded the stove, last measurement was taken at 49 hours 18 minutes. Here is 46 hrs 35 min, 48 hrs 20 min, and finally 49 hrs 20 min. I stirred up the coals each time but left the air control the same. That is why at the very end of the graph you see some fluctuation but the throttle remains at notch 6. And the chart plotting all the temperature points I recorded: Realize there are some big gaps between points when I was outside or sleeping, etc. I am very happy with the results! I was able to shut it down fairly quickly, but still needed 2 hours to get it into long stable burn. I could probably have shortened that some, and one or two less moves. From that point it ran about 28 hours completely untouched, and could have went much longer but I didn't want the CAT to get too close to 500. And it did not dip below 500 until about 40 hours. I reloaded shortly after the final picture, about 12:35. After raking the coals to the front I loaded it full, with 2 larger kindling pieces over the coals in front of the pile but everything else regular splits and a couple whole rounds. It didn't have a problem taking right off.
Good experiment and report, T-Stew. Always suspected the IS could go longer, but have been happy with 12 hour burns for the temps here lately. Looks like those EcoBricks pack a lot of BTU's and could release 'em slow under the right conditions. Thanks for the report.
This thread gave me the inspiration to try my own eco-brick test. I have used them to supplement before but have never run a complete load them, so I picked up three 6 packs (well four if you count the Labatt's) from the local Menards. Started the tests on Wednesday night but didnt realize I had an issue with my secondary air, which had caused a leak at the incoming air connection, so the first load burned down way too quick. Found the issue and corrected it for the Thursday night test. Got home from work Thursday afternoon and loaded 6 bricks in the Heartstone, 3 rows of 2 bricks. The bottom 2 rows were packed tight and I left about a 1/2 inch gap between the top 2 bricks. Put 2 of my homemade firestarters between the top 2 bricks and built a small "log cabin" out of very small kindling on top of the whole stack of bricks. Lit the starters at 4:00 p.m. and left the side door open until I could see that the top bricks had caught and the stack temp was at about 250, then closed the door. The stove was completely cold with no coals from the previous night, so it took forever to get the soapstone up to temp. With a normal fire it usually takes about an hour but this took about 2 hours. The stack temp also dropped to about 200 until the stove warmed up. Used the house furnace to bring the interior temps up to 66 and shut it down at 6:00 p.m. when the stove started cruising. Outside temps at this point were 18 and falling. With temps falling fast I decided to let the it burn a little hotter than normal (350-375 stack) until about 8:00 p.m, then started to slowly throttle down the primary to its normal cruising speed (250-275). Got the stove settled in and went to bed around 10:00, inside temps had climbed to 68 and outside temps had fallen to 9. Woke up for work around 5:00 Friday morning with outside temps at 3 and the furnace had kicked on but not sure when, the stove top was still warm which surprised me but there were no usable coals. As there wasnt adequate time to warm everything up before I left for work, I let it sit until I got home. I repeated the test Friday, with the exception of adding a couple small splits at bedtime, and had very similar results. The only difference is that I was able to reload and restart on coals this morning. Overall I was extremely impressed with how the eco-bricks performed. So start to finish the two tests ran for 13 hours each with only 6 bricks being loaded for each test. Although there wasnt any usable heat, I will guess after about 10 hours, we were also dealing with low single digit temps outside. If temps would have been more reasonable, I think I could have gotten good heat the entire 13 hours. Not bad for a probably 20 year old stove.
