Chimney fire after two weeks???

[NHWS]

Not all of us are experts. Not all of our family members are (or ever will be) experts. Still waiting on my stove install; still reading up on using the stove. Not everything is in the manual, e.g., what symptoms imply what kinds of problems, what tools to use (the stoves do not come with flue thermometers; which kind to use; how to install it; what the momentary readings and changes in readings over time mean), how to balance wood species, wood condition, load, wind, stack height, flue temperature. If it was all self-explanatory, there would not be any posts about flue fires or cat damage.

Still waiting on my stove install. No practice with one yet. Stoves look to be more complicated than toasters, less complicated than tractors. I have both a toaster and a tractor. I expect to be able to figure out how to use a cat stove, hopefully without making any mistakes that will damage it, people, or the home. Moving one lever until it clicks is not a problem. Remembering to do so every time in addition to watching for everything else that could indicate a problem may take some practice.

I expect that there will be more learning curve, and more potential for negative consequences, than there is for a toaster, and (maybe) less than for a tractor.

 

[bholler]

I think it's a silly argument. If moving one lever is too high a bar for anyone considering a stove, I'd argue we should take away their matches. I mean honestly... these people should not be allowed to operate basic home appliances.

I am sorry but you say time doesn't matter as far as closing the bypass. Even on a bk you can melt the retainers plus you are shooting lots of flames right up the chimney if there is much buildup it is very likely to start a fire. I agree neither type is terribly complicated to run. Some cat stoves are worse than others as are some non cats. I have run many stoves each one has its own quirks.

To me it's mainly about the cost of the cats and if it's worth that added cost in each person's situation

 

[Ashful]

I am sorry but you say time doesn't matter as far as closing the bypass. Even on a bk you can melt the retainers plus you are shooting lots of flames right up the chimney if there is much buildup it is very likely to start a fire. I agree neither type is terribly complicated to run. Some cat stoves are worse than others as are some non cats. I have run many stoves each one has its own quirks.

To me it's mainly about the cost of the cats and if it's worth that added cost in each person's situation

Agreed. And I said timing is not critical. If I wait 5 minutes, or 15 minutes... no big deal. I've even ripped thru half a load with bypass open on wide-open throttle 2 - 3 times, with no harm done, although I'm sure repeating that on a daily basis would shorten the life of the stove.

I was being called out on the use of a timer, as if that's somehow making a cat stove so complicated that it's worth considering that as a factor in choosing one over the other. It's a stupid argument to make, I only use the timer so I don't go outside for the day, before remembering to close the bypass. It's not a particularly time-critical operation.

If we really wanted to argue about it, I'd say non-cats must be more time-sensitive. With my stoves, I can let it rip an hour in bypass, then close bypass, turn it down, and be into "black box" mode in 2-3 minutes. No chance of run-away due to turning down "too late", ever.

 

[stoveliker]

Agreed. Though that is particular for (the t-stat) on a BK, and not generally true for all cat stoves.

 

[bholler]

Agreed. And I said timing is not critical. If I wait 5 minutes, or 15 minutes... no big deal. I've even ripped thru half a load with bypass open on wide-open throttle 2 - 3 times, with no harm done, although I'm sure repeating that on a daily basis would shorten the life of the stove.

I was being called out on the use of a timer, as if that's somehow making a cat stove so complicated that it's worth considering that as a factor in choosing one over the other. It's a stupid argument to make, I only use the timer so I don't go outside for the day, before remembering to close the bypass. It's not a particularly time-critical operation.

If we really wanted to argue about it, I'd say non-cats must be more time-sensitive. With my stoves, I can let it rip an hour in bypass, then close bypass, turn it down, and be into "black box" mode in 2-3 minutes. No chance of run-away due to turning down "too late", ever.

Most of the runaways you see here are due to the stove not being set up with proper draft

 

[Wildflush]

Most of the runaways you see here are due to the stove not being set up with proper draft

Question about that. Is the runaway caused by too much draft with a tall flue?

 

[stoveliker]

Most of the runaways you see here are due to the stove not being set up with proper draft

I did not have that impression. The need to turn down the stove soon enough during the off gassing stage to avoid not being able to turn it down as well if one is too late, appears to also be present in (non-cat, because easier air flow) stoves on normal height chimneys?

Of course it is true that too high draft will make more systems reach that point, and sooner.

 

[bholler]

Question about that. Is the runaway caused by too much draft with a tall flue?

Usually yes. But there can randomly be to much on shorter chimneys as well

 

[bholler]

I did not have that impression. The need to turn down the stove soon enough during the off gassing stage to avoid not being able to turn it down as well if one is too late, appears to also be present in (non-cat, because easier air flow) stoves on normal height chimneys?

Of course it is true that too high draft will make more systems reach that point, and sooner.

Every stove I have run has been set up with proper draft and I was always able to bring it under control at any point. And my last house had a 39' chimney

 

[Wildflush]

I did not have that impression. The need to turn down the stove soon enough during the off gassing stage to avoid not being able to turn it down as well if one is too late, appears to also be present in (non-cat, because easier air flow) stoves on normal height chimneys?

Of course it is true that too high draft will make more systems reach that point, and sooner.

I’ve had situations where the wood is off gasing and the secondaries are going crazy. In these instances seems like shutting the air down all the way eventually levels the STT off. At no point does it seem like I lost control. Other variables are draft and amount of fuel in the firebox.

 

[Ashful]

Most of the runaways you see here are due to the stove not being set up with proper draft

... and I suspect the rest are either:

1. A very small number of poorly-designed models, especially prone to this behavior
2. Poorly-maintained stoves, with leaky door gasket, etc.

On that first point, there were one or two stoves in particular, with which I remember several of our posters struggling ca.2012. I don't recall the specific models now, but it seems we see far fewer of those posts, in recent years.

 

[bholler]

... and I suspect the rest are either:

1. A very small number of poorly-designed models, especially prone to this behavior
2. Poorly-maintained stoves, with leaky door gasket, etc.

On that first point, there were one or two stoves in particular, with which I remember several of our posters struggling ca.2012. I don't recall the specific models now, but it seems we see far fewer of those posts, in recent years.

Oh absolutely some of the cheap box store stoves are prone to it. But a few higher end ones had issues as well.

And absolutely poor maintenance on any stove will cause issues

 

[stoveliker]

That any one of us has proper control does not say anything about the risk of runaway of a certain stove with the proper chimney height. After all we're tuned in experts here. We're here because we think about stoves.

 

[showrguy]

I ran my BK King 1 1/2 seasons on a 35’, 8” chimney straight off of the stove, and never had an overfire, even with a draft of .23-.26..
After that I added a pair of things BKVP can’t talk about,,,lol…
Now I can dial it right to BK’s specs. no matter what conditions are like outside..

 

[Woodsman on the Plains]

Update#1
I really, really like how this stove burns now. Now that I've installed that "draft control device" and figured out through trial and error different loading schedules and the best one that suits my needs I'm officially a BK fan! I'm able to calm my draft down on non-windy days to right around. 07-.08 which is slightly high out of spec but no where near what it was. Getting around 600 degree flue temps a few hours after start up, then the rest of the day until around hr 8 it's consistently 400, then it starts tapering off but cat is still active and at hr 10 I'm around 300 degree flue temps. I'm pretty sure the cat has settled down after being overactive for the first few cord last year. Also to comment on @showrguy post, I can now run the thing full bore for 30 minutes and only hit 800 flue temps, so that has calmed down significantly as well.