All EPA approved Wood furnace owners; I need your creosote Advice!

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A good secondary burn is an amazing thing to watch!

I see two types in my Caddy. Sometimes the flame burns right off of the secondary air tubes in the top of the firebox. It looks like a burner on a gas furnace! This is the type that you see in the link in Mrpelletburner's vid at post #15. This seems to be the type of burn I usually get in a hot firebox with a fresh charge of wood.

Sometimes, it is more subtle. I will see what I call ghost flames, essentially the entire firebox will have flames filling the air space above the wood. Davewoz, just like the vid you have at post #13. I get this type of secondary burn usually later in the burn cycle, maybe a couple of hours in when the load of wood is burned down and starting to convert to red hot coals.

Either way, it is very efficient and clean burning - and kind of mesmerizing to watch!
Good luck Davewoz with your Max, I am starting season #4 and have been very happy with my Caddy.
 
Not much to add. As usual @brenndatomu has it covered. Once you get your furnace, and wood dialed in then you'll spend hardly anytime tending your wood furnace. Not unless you like to tinker and want to the build the next SpaceHawk1000 ;).

In the morning, evening, and when I get home from work. I rake the coals forward, throw more wood on, set the timer, and walk away. Every few days I'll empty the ash pan when I go out to feed the cows. I fought with wet wood the first year I started burning our catalytic wood stove and it definitely makes it frustrating. I learned my lesson after that.

Good luck, and you got one heck of a deal.
 
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What do you guys think, should I replace this? Not sure what it’s called but like a foam firebrick I’m assuming. It’s in the top of the firebox and the gap was in the front of furnace for what I’m assuming the smoke goes from the front to back to burn more of smoke?
 
Yeah it will need replaced...not an emergency though...you can push it together as best possible and order a new one...FYI, they are a bit pricey. You can also make one out of 1" ceramic insulation board that is commonly available online (ebay amazon etc) but still not super cheap.
The OEM one from SBI may be a bit more durable, maybe?
 
That could affect the secondary burn somewhat...depending on the gap...but if its pushed together, shouldn't be too much...I'd still get a new one coming though, if it breaks and falls completely apart the firebox will just turn into a "campfire in a steel box" basically...not clean, not very efficient.
 
So 12" x 24" is big enough to make 1 new one?
I usually try to order a big enough piece to make 2...makes it about half price of OEM usually...
 
So 12" x 24" is big enough to make 1 new one?
I usually try to order a big enough piece to make 2...makes it about half price of OEM usually...

Yeah it’s 2 pieces right now both are 11x19. About a 3” gap in the front of the furnace that goes above it to the flues

I also took part those tubes and they were all fairly clean not much dust in them at all. Above that fiber board there was at least a quarter inch of fine ash dust sitting on them.
 
I also took part those tubes and they were all fairly clean not much dust in them at all. Above that fiber board there was at least a quarter inch of fine ash dust sitting on them.
I did that one time. Never again. I just vacuum mine out once a year, and call it good.
 
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I’m thinking my wood is a little too moist, 10* outside now and that’s my smoke this morning with a good hot fire. plenum steady at 132* with the blower on. Other things I’m reading my smoke should be a lot less...although it is more like a vapor and dissipates fairly quickly
 
As cold as it is...you'll see that "steam"...for the first hour or so anyways. You have to realize that even "dry" firewood can be 15-20% water by weight...that's quite a bit really.
Do you have a barometric damper? Peek in there and see what your pipe looks like, if its tan or brown dry/fuzzy soot, you are doing OK. That's not to say that the chimney might not look a little worse that that though, maybe?
 
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What do you guys think, should I replace this? Not sure what it’s called but like a foam firebrick I’m assuming. It’s in the top of the firebox and the gap was in the front of furnace for what I’m assuming the smoke goes from the front to back to burn more of smoke?



Couldn't you just use a high temp cement and glue the 2 pieces together? I did this once with an old fireplace and it held up for years.

Eric
 
As cold as it is...you'll see that "steam"...for the first hour or so anyways. You have to realize that even "dry" firewood can be 15-20% water by weight...that's quite a bit really.
Do you have a barometric damper? Peek in there and see what your pipe looks like, if its tan or brown dry/fuzzy soot, you are doing OK. That's not to say that the chimney might not look a little worse that that though, maybe?

To add what brenndatomu said... From what I have experienced first hand, “wet wood” can have a “dirty” smoke appearance where that “steam” smoke will have a very clean white appearance.
 
Couldn't you just use a high temp cement and glue the 2 pieces together? I did this once with an old fireplace and it held up for years.

Eric
Yeah, you could. Its not cheap either.
 
Oh, that's what you meant...I have never tried that...might work short term...I have never had much luck with it on the things I used it on...I may have not been using it how it was meant to be though either.
I thought you were talking about the cement that is made for ceramic insulation board...that's kinda pricey...or you have to buy it in a quantity that makes it impractical for a small repair like this.
I got some from a buddy that builds rocket stoves...he just gave me a blob of it to try to repair a broken baffle...haven't tried it yet. He said it would be stronger than the board itself though...
 

Not bad I’ll get that and keep this as a backup when I repair it, sounds like these go bad after a while. I cut a few pieces of wood in half and had a moisture content of .2 to .25 so definitely a little wet, hopefully next month or so with a fan on it 24/7 it’ll get it all down more. I can definitely tell a difference of the flames when pushing those 2 pieces together, I think I definitely had smoke escaping.
 
Not bad I’ll get that and keep this as a backup when I repair it, sounds like these go bad after a while.
I've had my furnace for 7 years or so and mine is still in one piece. I definitely could see how someone could break it with a piece of wood. But under "normal wear and tear" I am not sure how it could go bad. I'm wondering if yours could of possibly cracked when you moved the furnace. Hard to tell really.
 
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Not bad I’ll get that and keep this as a backup when I repair it, sounds like these go bad after a while. I cut a few pieces of wood in half and had a moisture content of .2 to .25 so definitely a little wet, hopefully next month or so with a fan on it 24/7 it’ll get it all down more. I can definitely tell a difference of the flames when pushing those 2 pieces together, I think I definitely had smoke escaping.

The baffle on my wood insert cracked in half front to back. I used hi temp stove cement and has held up for a whole burning season before I got my tundra furnace.
 

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