Those dang back corners, prevent firebox corrosion.

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Highbeam

Minister of Fire
Dec 28, 2006
20,873
Mt. Rainier Foothills, WA
I burn my princess on low 99% of the time with very dry low btu woods like Doug fir and maple from a shed. The cat stays nice and hot, the probe for the flue meter stays brown and dry but the firebox can get pretty icky. The wet looking firebox deposits on the bare firebox steel can cause corrosion, especially in the corners, and this is what the deposits look like. To remedy this I’ll need to burn a half full firebox of wrist sized splits on high. That won’t clean the glass but it will dry out that tar stuff and allow it to flake off.



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Try some Cre-Away, if you can. It may not be good for a catalyst.
Nope. Not into burning trash in my cat stove. High heat will burn it out. Once per week is the BK recommendation.
 
I told you about the wrong product. This is the one I meant to tell you about that is safe for your catalyst.


Your right. You shouldn’t burn “trash” in your cat stove.

Might want to give the old time adage of burning hot once per day a try as the pictures prove once a week only burns it out, but doesn’t prevent it. If you prevent the build up you won’t have to worry about corrosion eating holes in the corners of your stove. Prevention seems the key to maintaining stove life, not removal.
 
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Interesting. I have build up in my corners too but it’s not shiny like that. Mine is thicker and duller colored. If I poke it with the fireplace poker it falls off. Probably just because of the different wood species.

My plan is to remove all the fire bricks in the spring and scrape the inside of the stove out. Also I’m going to get a skinny wire brush so I can get behind the side (inside) heat shields.
 
Back to back 24 hour burns of softwood. Don't even need kindling. The stove is sized just right for my home, fuel, and for minimum burning effort of 24 hour cycles. Burning it hot enough to dry out the firebox will throw off the whole cycle. So I certainly wouldn’t do it every day. Otherwise I might as well burn a noncat!

Just wanted to show folks what happens with very dry wood burned very slowly. Clean emissions and top of stove but that cold firebox metal gets icky.
 
Back to back 24 hour burns of softwood. Don't even need kindling. The stove is sized just right for my home, fuel, and for minimum burning effort of 24 hour cycles. Burning it hot enough to dry out the firebox will throw off the whole cycle. So I certainly wouldn’t do it every day. Otherwise I might as well burn a noncat!

Just wanted to show folks what happens with very dry wood burned very slowly. Clean emissions and top of stove but that cold firebox metal gets icky.
That looks like my in the shoulders.
 
That looks like my in the shoulders.

Yes, my climate is probably equivalent to the shoulder seasons of the interior. We have a 9 month heating season but it's usually above freezing out. Occasional week of very cold weather but usually pretty comfortable.

During the cold snaps, it is pretty easy to keep cleanish glass and dry firebox walls. Also, if I needed to burn off the tar during a cold snap I wouldn't likely have a problem with overheating the house.

Definitely burn that tar off before the summer slumber.
 
With a 9 month heating season do you find it tough to maintain a 1 to 3 year advanced supply of wood dried and ready to go?

Here we usually need heat beginning in early to mid-October and burn until at least mid to late April and occasionally early May. Certainly need heat Nov-March, so about 5+ months.
 
With a 9 month heating season do you find it tough to maintain a 1 to 3 year advanced supply of wood dried and ready to go?
The Western Washington heating season sometimes starts in mid-September, and might not end until the first week of July. But for most of that the overnight lows are in the 40s and daytime highs may be in the 50s. Almost always burning low-and-slow, so Highbeam's post about firebox corrosion is good info.

Hardwoods are rare here. Most of what I burn is hemlock, alder, pine, and fir. The lower BTU wood means collecting/processing/storing more cords. The good news is that it dries fast, so 1 to 2 year cycles seem to be long enough.
 
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With a 9 month heating season do you find it tough to maintain a 1 to 3 year advanced supply of wood dried and ready to go?

Here we usually need heat beginning in early to mid-October and burn until at least mid to late April and occasionally early May. Certainly need heat Nov-March, so about 5+ months.
In the end it's not more work after the first rush to get ahead. Just process one years worth of wood each year...
Gotta process what you burn anyway, regardless of whether one is on the one or three year plan.
 
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I get the same in the back of my firebox. I was told it’s pretty normal way in the back like that. Usually after I use a scoop of creosote removal on the fire it flakes right off.
 
I get the same in the back of my firebox. I was told it’s pretty normal way in the back like that. Usually after I use a scoop of creosote removal on the fire it flakes right off.
Do you need to burn it on high with that scoop, or just a normal burn?
 
That's substantially cleaner than one of my fireboxes, which only ever sees 24-hour cycles (low burning). I'm not losing any sleep over it.

My take on these stoves is that they're not exactly family heirlooms. They're just another appliance, like any refrigerator or dishwasher. Use it as suits your convenience, and don't hesitate swapping it out when it's past it's prime, or the next better thing comes along.
 
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With a 9 month heating season do you find it tough to maintain a 1 to 3 year advanced supply of wood dried and ready to go?

Here we usually need heat beginning in early to mid-October and burn until at least mid to late April and occasionally early May. Certainly need heat Nov-March, so about 5+ months.

No problem at all. In fact, I had so much that I sold about 5 cords last year. My woodshed holds 11 cords and I currently have about 6 out on pallets top covered. Selling wood is pretty enjoyable. My last load of logs came on a western log truck. 40’ long logs up to two feet across. I enjoy processing.
 
That's substantially cleaner than one of my fireboxes, which only ever sees 24-hour cycles (low burning). I'm not losing any sleep over it.

My take on these stoves is that they're not exactly family heirlooms. They're just another appliance, like any refrigerator or dishwasher. Use it as suits your convenience, and don't hesitate swapping it out when it's past it's prime, or the next better thing comes along.

I agree that these are not lifetime stoves. Much longer lasting than my hearthstone though!
 
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As a follow up, it’s supposed to snow tonight so I let the house cool and then did a clean out burn to demonstrate how this tar converts.

The fire only lasted about 2 hours and was log cabin stacked fir splits about the thickness of my wrist. I kept the stat pretty high but kept the cat under 1500 and the chimney under 900.

The tar puffed up like popcorn and popped off like a big sheet of beef jerky. Clean metal underneath. The bricks didn’t clean up. In my experience there is no accumulation behind the bricks.

If I repeated the high burn load it would further degloss that metal. That’s what I do in spring.



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No problem at all. In fact, I had so much that I sold about 5 cords last year. My woodshed holds 11 cords and I currently have about 6 out on pallets top covered. Selling wood is pretty enjoyable. My last load of logs came on a western log truck. 40’ long logs up to two feet across. I enjoy processing.
That sure makes it easier, but a far cry from doing it the old fashioned way, processing it in the woods. I’m not down playing the work involved from processing a truck of logs. It’s still a bunch of work. It’s just different chasing it all around the woods, processing logs and tree tops…that takes far more time. Of course, I bought my last three cords and them delivered and that’s even easier than logs being delivered, although I would buy logs that way too if I could find someone to buy a truck load from. I’d enjoy working them up in my yard. Just don’t know anyone around here who sells logs by the truck. Probably would have to come out of eastern Ohio, southern Indiana, or Michigan for me.
 
That sure makes it easier, but a far cry from doing it the old fashioned way, processing it in the woods. I’m not down playing the work involved from processing a truck of logs. It’s still a bunch of work. It’s just different chasing it all around the woods, processing logs and tree tops…that takes far more time. Of course, I bought my last three cords and them delivered and that’s even easier than logs being delivered, although I would buy logs that way too if I could find someone to buy a truck load from. I’d enjoy working them up in my yard. Just don’t know anyone around here who sells logs by the truck. Probably would have to come out of eastern Ohio, southern Indiana, or Michigan for me.

There are choices. Your way is a far cry from the old fashioned way of axes, mules, and bow saws. I’ve done it with tractors in the woods also and I prefer running saws and splitters.
 
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