Canawick Bricks In Furnaces

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clyancey

New Member
Nov 17, 2021
2
Maine
Hey guys. First time posting in here.
We are trying an experiment this winter and using Canawick bricks instead of cord wood in our indoor furnace. We have a Kerr Scottsman hot air furnace and the fire box is a barrel shape.
So far the bricks are kind of a problem. When we go to bed at night I stoke the furnaces with a full sleeve of bricks and stack them like dominos going towards the back of the firebox. So the problem is we are getting some pretty healthy backfire every night and our basement fills with smoke. SO I am thinking I can not stoke the stove before bed and then turn the heat down because the damper then closes. I am concerned that if I stoke the stove earlier in the evening and then turn the heat down that it will still backfire.
-Is there a proper way to stack those bricks?
-What should be my routine for the night?
-Am I missing something (ie: I need to replace my rope gasket?)

If this is in the wrong forum I apologize and thanks for any help.
Charlie

IMG_2822.jpeg IMG_2823.jpeg
 

brenndatomu

Minister of Fire
Aug 21, 2013
6,766
NE Ohio
You probably won't be able to use 100% bricks...they are very dry and start to off gas pretty hard the first hour or two...many people find they work better mixed in with cordwood...
 

clyancey

New Member
Nov 17, 2021
2
Maine
That was what I was afraid of. I got in touch with Canawick and asked if there was a way to stack the bricks that might help but so far their best suggestion is to stack the bricks with the logo facing up. Come on man, you got to give me more than that. I guess we are going back to cordwood in the future and will just slowly eat through these bricks and supplement.
 
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Rockstar1346

New Member
That was what I was afraid of. I got in touch with Canawick and asked if there was a way to stack the bricks that might help but so far their best suggestion is to stack the bricks with the logo facing up. Come on man, you got to give me more than that. I guess we are going back to cordwood in the future and will just slowly eat through these bricks and supplement.
I have not tried 100% bricks but I’m pretty sure the package says not to use more than 3 at a time? But I find they work amazing when mixed with cord wood.I throw one at the bottom stack kindling around it with paper and wood in a log cabin around it makes an amazing quick fire. Then before bed I throw 2 at the top of my logs I have stacked in there keeps it going all night.
 
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sloeffle

Minister of Fire
Mar 1, 2012
894
Central Ohio
I have not tried 100% bricks but I’m pretty sure the package says not to use more than 3 at a time? But I find they work amazing when mixed with cord wood.I throw one at the bottom stack kindling around it with paper and wood in a log cabin around it makes an amazing quick fire. Then before bed I throw 2 at the top of my logs I have stacked in there keeps it going all night.
I've had very similar results. I ran into some wet wood last year and started using them myself. I did notice the price went up a $1 a bundle from last year at my local Rural King. That's to be expected though, I guess.
 
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NorMi

Member
Nov 18, 2021
110
Northern LP, MI
I'm actually testing my furnace with some pressed sawdust bricks today by chance, envirobricks, which should yield very similar results. So far, I am on my first test run, and sticking to the Intertek 10lbs/cu.ft. "full load" firebox loading for cordwood. My furnace is a 3.4 cu.ft, so I loaded (10) 3.33 lb. bricks into a luke warm stove with about 2 lbs. of coals at 11am this morning. It's a forced induction, so I let it run for 30 minutes to re-heat the stove, and shut it off. It was still lightly smoking at the stack an hour later, so I did another draft fan run for 25 minutes and then set it to idle. It cleaned up to zero smoke at 1 hour 22 minutes from first fire. It probably would have been shorter had I let the furnace reach full temperature on the first firing. I plan to test another full load tonight on a hotter stove when this load stops producing enough heat to cycle the duct blower. I'll report back.
 

Rockstar1346

New Member
I've had very similar results. I ran into some wet wood last year and started using them myself. I did notice the price went up a $1 a bundle from last year at my local Rural King. That's to be expected though, I guess.
Yupp me an you were in the same boat then! I moved into a new house last fall with no wood readily available so I bought” seasoned” wood which was as green as you could get so I supplemented 2 of these every fire to get it nice and hot then mixed all winter worked out great but yeah the price did go up here too. So did everything else too I guess
 
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NorMi

Member
Nov 18, 2021
110
Northern LP, MI
IMG_20211119_175447188.jpg

That's the remnants of the 10 bricks I used after a 7 hour burn time at idle, decided for a hotter reload test at 6pm. The duct blower was still cycling heat at about a 6-7 minute interval at this phase. For the next test, I'm going for a long, overnight burn in a more "worst case" condition with these bricks. I spread the coal bed down and loaded (12) 3.33 lb. bricks for 40 lbs. total - roughly 118% of a full load, plus a larger coal bed.
IMG_20211119_175552863.jpg

Slightly evened out the coals/remnants.
IMG_20211119_180017722.jpg

Loaded 12 bricks.

For this run I wanted to get the firebox up to temps and secondaries burning as quickly as reasonable, so I start with draft blower on, a 1/2" cracked load and ash door. At 5 minutes, I close the load door, and at 10 the ash door. At 12 minutes the smoke was very light, and at 20 the stack was clear. I idled the draft blower at 20 minutes, but there was still too much fuel and light smoke returned. I did 10 minute tests/checks every time any smoke returned when I switched the draft blower off. At 50 minutes it was clear at idle and it will burn for the overnight test. 50 minutes to [email protected] for an overfuel is not too bad, but also longer than it would take on cord wood in this furnace.

I've never had any puff back on this arrangement so far on any other loads, and I have a habit of making sure it's clear at the stack before idling down, so that may be part of it. As for price, these bricks I picked up at $280/ton which is about 30 or 40 over what I saw last year I think. Split seasoned cord wood sells for about $225/cord up here and a log truck with 8' trunk cuts buying 19-20 cords at a time runs about $100/cord unprocessed.
 
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