Marginal wood

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BrownT10

Member
Jun 1, 2021
136
Massachusetts
So, I have posted about flue temps recently with my Osburn 3300 and have been struggling to keep the stove up to a hot temperature. I am aiming for the 700° range as it appears that is where the best secondary burns are. My flue temps can still ready around 400 to 450° but then slowly creep back down. That is with the key damper closed.

So back to the struggle, can't keep the firebox hot enough so I check so fresh splits and low and behold MC of some of the wood is 20-22%. I wouldn't have even known that with my Defiant as it would devoured those with no issues. So, it appears that with the humid summer my wood may not be ideal. It is 2+ years stack and top covered for a year, but I did end up replitting alot of the big pieces when I got the new stove.

So now I am trying to navigate the marginal wood issue. Some is quite a bit less than 20% but some is definitely more. I will split some and leave anything too high in a separate pile and try to mix it in. I have about 3 cord in the basement so may rearrange it to use better wood first. I was concerned with the heat output of this stove but seems dry wood will make this stove a good heater. As I have burned it hot this afternoon. I do have a some black buildup on the visible clay liner bit wanted to figure this out before the wet wood presents an issue.

I do work for a company that intended to construct new homes over the winter and I should have access to framing lumber scrap. I was thinking about mixing this in to keep things hot? Has anyone had reasonable success doing that? I have been discouraged with this stove but now the non ideal wood plays a huge factor in these new stoves. Any recommendations or suggestion would be appreciated.
 

MEngineer24

Member
Dec 6, 2020
170
WV
So, I have posted about flue temps recently with my Osburn 3300 and have been struggling to keep the stove up to a hot temperature. I am aiming for the 700° range as it appears that is where the best secondary burns are. My flue temps can still ready around 400 to 450° but then slowly creep back down. That is with the key damper closed.

So back to the struggle, can't keep the firebox hot enough so I check so fresh splits and low and behold MC of some of the wood is 20-22%. I wouldn't have even known that with my Defiant as it would devoured those with no issues. So, it appears that with the humid summer my wood may not be ideal. It is 2+ years stack and top covered for a year, but I did end up replitting alot of the big pieces when I got the new stove.

So now I am trying to navigate the marginal wood issue. Some is quite a bit less than 20% but some is definitely more. I will split some and leave anything too high in a separate pile and try to mix it in. I have about 3 cord in the basement so may rearrange it to use better wood first. I was concerned with the heat output of this stove but seems dry wood will make this stove a good heater. As I have burned it hot this afternoon. I do have a some black buildup on the visible clay liner bit wanted to figure this out before the wet wood presents an issue.

I do work for a company that intended to construct new homes over the winter and I should have access to framing lumber scrap. I was thinking about mixing this in to keep things hot? Has anyone had reasonable success doing that? I have been discouraged with this stove but now the non ideal wood plays a huge factor in these new stoves. Any recommendations or suggestion would be appreciated.
Yes mixing in some good dry (no treated of course) wood scraps will help! I know some on here have even used old busted up pallets too. The pressed sawdust bricks without any fillers/binders/waxes are also an option for you.
 

ABMax24

Minister of Fire
Sep 18, 2019
1,318
Grande Prairie, Alberta, Canada
I have 2 thoughts, either your wood is quite a bit wetter than 22% or there is not enough draft to get the wood burning hot. That 3.3cuft firebox should be an inferno with good wood and sufficient draft. Are you stuffing the firebox completely full and then letting it do it's thing? Or is this with partial loads?

That being said my Osburn much prefers wood under 20% moisture, and I really like it under 17%, but even at 22% I can get good heat from the stove, it just takes longer to get hot and the chimney gets buildup quicker with more smoke out the cap.
 

BrownT10

Member
Jun 1, 2021
136
Massachusetts
Not sure if you followed the thread about flue temps, but this is a about a 25 chimney and has huge draft. I had to completely close the key damper to slow it down because of high flue temps. So I have been fighting the draft a little bit which I am sure decreases the inferno? With the door open for a few minutes this this is ripping pretty good. I am just loaded with a partial load, maybe 60% and had 700° stovetop, 400° flue and angry secondary with little smoke out the chimney, but its night and smoke at night can be deceiving.

As you said I have some buildup in the clay liner and ran the soot eater up it over the weekend to clean it out some. I think with dry wood mixed it I can get through this winter, but will likely have my sweep inspect/clean mid-season which I have never had to do.

My setup isn't ideal with my clay liner, I know, but with dry wood and good draft I think I can make it work. The days of chucking big splits into the Defiant and not worrying about MC are over..maybe it's still over in the corner! Need to figure this new beast out because it throws serious heat this afternoon using dry wood.
 

marty319

Feeling the Heat
Nov 17, 2014
423
Belair mb
Dry wood is a must with this stove Travis.i have yet to let my 3300 rip yet as I will get thrown outta here,but that said I have had a couple good fires in the morning,but only 3 or 4 splits, this 3300 will rock when it gets cold enough to let it rip.
 

ABMax24

Minister of Fire
Sep 18, 2019
1,318
Grande Prairie, Alberta, Canada
Not sure if you followed the thread about flue temps, but this is a about a 25 chimney and has huge draft. I had to completely close the key damper to slow it down because of high flue temps. So I have been fighting the draft a little bit which I am sure decreases the inferno? With the door open for a few minutes this this is ripping pretty good. I am just loaded with a partial load, maybe 60% and had 700° stovetop, 400° flue and angry secondary with little smoke out the chimney, but its night and smoke at night can be deceiving.

As you said I have some buildup in the clay liner and ran the soot eater up it over the weekend to clean it out some. I think with dry wood mixed it I can get through this winter, but will likely have my sweep inspect/clean mid-season which I have never had to do.

My setup isn't ideal with my clay liner, I know, but with dry wood and good draft I think I can make it work. The days of chucking big splits into the Defiant and not worrying about MC are over..maybe it's still over in the corner! Need to figure this new beast out because it throws serious heat this afternoon using dry wood.

It's possible you have too much draft then, and are pulling in too much secondary air cooling the firebox and stovetop.

Out of curiosity is there a stanless steel sheet welded to the underside of the stovetop in the 3300 like SBI has done to some of their smaller models?
 

begreen

Mooderator
Staff member
Nov 18, 2005
91,301
South Puget Sound, WA
Be sure to have the flue system cleaned at least once for every cord of wood burned. Poorly seasoned wood cools down flue gases which often leads to excessive creosote buildup.
 

kennyp2339

Minister of Fire
Feb 16, 2014
6,279
07462
Its been a little to warm to be using a key damper, why not do a few burns with it opened to see if that changes anything, I'm assuming your getting your temps by probe? Has the metal probe been cleaned? Have you tested your draft officially with the right equipment?
 

BrownT10

Member
Jun 1, 2021
136
Massachusetts
The stove has been running much better with smaller splits and using the dry pieces. I have not noticed a welded piece of stainless under the stove top? What was the purpose for this in smaller stoves?

begreen, I intend to have the chimney inspected and cleaned as you mentioned. I see no visible smoke when I open the cap at the tee, but there is some smoke coming from the chimney at times, certainly nothing like my previous smoke dragon. I was thinking of using Cre-Away to try to help out, can this powder be pit directly into the class A cleanout cap? Would you recommend using this to help?

Kenny, it has been warm however the stove will rub wild without the key damper. Even if I just crack the damper from horizontal I can hear the air rush through the stove pipe. I know the draft is very strong not sure what a real test of that would do other than confirm that. Unless I am trying to reduce it to a certain measurement? I would love to try a few burn, maybe I will start medium size fire, but that flue reading will likely be up over 600° reading on the surface of a single wall pipe in no time. As of now, my only means of slowing it down is the key damper. I could try turning the air down sooner but have found that the flames become unstable until the firebox has reached temp. I have found the firebox temp lags way behind the flue temp. Maybe just a timing issue.
 

begreen

Mooderator
Staff member
Nov 18, 2005
91,301
South Puget Sound, WA
cre-away is only necessary if there is serious creosote build-up. It won't hurt but it is not a substitute for a proper inspection and cleaning. Have you considered cleaning the flue system yourself? Most accumulation will be at the coolest section of the chimney which is usually at the top. Is access safe and relatively easy or very challenging?

How is the stovepipe temp being measured? Is this single-wall with a surface thermometer or double-wall with a probe?
 

ABMax24

Minister of Fire
Sep 18, 2019
1,318
Grande Prairie, Alberta, Canada
The stove has been running much better with smaller splits and using the dry pieces. I have not noticed a welded piece of stainless under the stove top? What was the purpose for this in smaller stoves?

My understanding is this plate exists to shield the top from the heat of the flame, and for emission purposes to prevent the flame from being quenched when touching the cold steel of the top.

This acts as a thermal break in the stove, limiting heat transmission through the top, but if your stove doesn't have this plate then this isn't a factor.
 

BrownT10

Member
Jun 1, 2021
136
Massachusetts
There is no safe access from the top, at least for me. I run a soot eater up from the inside cleanout, but not real sure what's happening up top, but presumably dirtier. I plan on having a sweep check things out mid season for peace of mind.

The temps are from a surface thermometer on a single wall pipe. The flue is hotter now than wirh the smoky Defiant I was running.
 

stoveliker

Minister of Fire
Nov 17, 2019
2,821
Long Island NY
The sweep will be very busy mid season. Book him now for that time. May already be too late...
 

MMH

Feeling the Heat
Jan 21, 2019
486
NV
If you can let the wood sit longer, I’d say split the bigger stuff again and let it dry; if not mix it with the good wood or any other idea you have (like untreated lumber) and sweep more frequently.
 

begreen

Mooderator
Staff member
Nov 18, 2005
91,301
South Puget Sound, WA
If you don't mind the look, consider bringing the wood into the house in big boxes or plastic totes in order to help dry it out. A week or two indoors can make a notable difference.
 
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BrownT10

Member
Jun 1, 2021
136
Massachusetts
It is actually all stacked in the basement and has been for a few weeks with dehumidifier going. I am hoping that I can knock some moisture down as it is in the heated space to drive out some moisture. I intend to split then into smaller pieces and burn hot, maybe add in pallets or untreated lumber if needed.
 
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BrownT10

Member
Jun 1, 2021
136
Massachusetts
I have been having pretty good success running the stove without the key damper. I have split the bigger pieces smaller and everything catches pretty quick. I have to change my loading method with how I ran the Defiant. I will now add a bottom layer and allow that to catch for a few minutes and then keep adding a bit at a time over the first 10-15 minute until everything is burning good before I close the air down in increments. Then the secondaries get strong and not visible smoke in the chimney today. I have found that loading it full and try to char the whole box ends up with alot of smoke and a bunch of creosote. I have the shipping pallet to mix in and a builder friend is going to save me the untreated scrap lumber if I need it.

My wife like not use the key damper as it simplifies things a bit. Once colder weather hits we will see if I need the damper or not, could at least slow the draft some and put more heat into the house. Think I may have this stove figured out, at least I hope.
 
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