Fire brick corrosion and growth(??!!) . Why?

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shaggerty

New Member
Nov 27, 2018
2
Lynnwood, WA
Ok, so I have a Regency stove insert I have been using for 4 years now, really steadily from Oct - March, and just this year had something really strange happen.

So in the middle of the firebox, on top of the fire brick lining, I started getting this super crusty buildup I had never had before. It got really bad the last few weeks and finally tried to really clean it up to get down to clean bricks, but whatever the growth or deposit was seemed to grow from but also eat away at the firebrick! I took a piece of brick and the crusty stuff to a fireplace shop and the hardware store, and no one had seen anything like it.

Help!

The main difference in what I am burning this year is that there is some Spruce in the mix, and some fairly dry but not fully seasoned big leaf maple. But I have burned somewhat damp wood in the past and not had ANYTHING like this. There appears to be a nail imbedded in the crusty stuff?

One person thought it was moisture coming down my chimney, but that is not the case. It was windy and raining last night and I put clean sheets of white paper in the fireplace overnight, not a single drop on them.

Anyone have any ideas? See pics

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It's a clinker. Pellet stoves get them more but wood stoves do too.
 
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Yup, clinkers. They didn’t break the brick but they can stick to bricks and if you are rough removing them it can break the bricks.

It’s mineral. Think sand melting into glass.
 
Main thing your not doing anything wrong so just keep burning, just be careful taking them out.
 
i get them all the time, big ones too.... other people have never seen them.... I think it has something to do with the way the air intake is set up. If the ash gets really hot it melts the minerals and you get the clinkers... Dirty wood (dirt/sand/bark) definitely appears to exacerbate the issue. I have never had them attach to the brick. Just something in the ash to scoop out and dispose of.


a thread a while ago of mine... biggest clinker contest...
https://www.hearth.com/talk/threads/biggest-clinker.79475/
 
i get them all the time, big ones too.... other people have never seen them.... I think it has something to do with the way the air intake is set up. If the ash gets really hot it melts the minerals and you get the clinkers... Dirty wood (dirt/sand/bark) definitely appears to exacerbate the issue. I have never had them attach to the brick. Just something in the ash to scoop out and dispose of.


a thread a while ago of mine... biggest clinker contest...
https://www.hearth.com/talk/threads/biggest-clinker.79475/
I think your clinker wins
 
I am ambivalent about pumice bricks. See an old thread of mine: https://www.hearth.com/talk/threads/wow-the-quadrafire-brick-is-crappy.7655/ . It did the same as yours after not that long a time. You think it's some deposit, touch it a little and the brick dissolves. No problem after replacing with the solids. Running well for current owner, (friend).

I've had one stove company, not sure if it was Quad or Hampton, say that: "ahhh, you're okay until it gets down to 1/4". 1/4" ??? Yeah, great.

The dealer for my current stove doesn't even stock Regency/Hampton pumice bricks-he uses the solid firebrick (this is from memory). Have to special order tham.

My Hampton bricks have been holding up much better.
 
i get them all the time, big ones too.... other people have never seen them.... I think it has something to do with the way the air intake is set up. If the ash gets really hot it melts the minerals and you get the clinkers... Dirty wood (dirt/sand/bark) definitely appears to exacerbate the issue. I have never had them attach to the brick. Just something in the ash to scoop out and dispose of.


a thread a while ago of mine... biggest clinker contest...
https://www.hearth.com/talk/threads/biggest-clinker.79475/

I think I passed one of these similar to size through my urethra a few years back. :)
 
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