I'm done with the Dauntless after a runaway fire

[manofstihl]

This is our third year with the Dauntless. I can’t say that I love the stove, but I was doing decently well with it. As a ballpark estimate, we have had somewhere between 80 to 120 fires in it. We have had it professionally installed and, after each season, had the chimney professionally cleaned.

I think we are done with this stove, though, after what I went through tonight.

We started a fire around lunchtime. The temperature today was really cold. It was around 11 degrees when I went walking very briefly around 5:30.

About 6:45, I reloaded the stove with a mixture of maple and oak, all seasoned two years. The coal bed was thick. The flames started quickly under the wood that I had loaded (I usually put a two smaller pieces on the bottom because the doors get really smoked up if I don't).

After about ten minutes, I closed the bypass damper. I do not remember the stove top temperature, but I do remember that the probe was in the middle of the damper range.

The damper made a sound like a blowtorch, which it has done multiple times in the past. I had been planning to head into the basement to clean, but the sound continued, which was abnormal. I thought something might be wrong and decided to stay upstairs instead. When I noticed that the flames were dying on and off, I opened the bypass damper.

Flames were instantly everywhere inside the firebox. I’m used to a certain amount of flame, but this was more than normal. This concerned me, so I dialed the air back. Shortly after—and I don’t know the exact amount of time, but it seemed like only a few minutes—the inside of the double-wall stove pipe started to turn orange. Smoke came from the stove and activated our smoke detector.

At this point, I was really concerned that I was about to burn the house down, so I located our Chimfex, ignited it, and placed it into the firebox. Then I called the fire department, and we evacuated to a neighbor’s house.

Thankfully, by the time that the fire department arrived, the fire was somewhat more under control. One of the firemen mentioned that the cast-iron griddle on the top was glowing, which I did not see. They let it burn for about fifteen more minutes, but when it was apparent that it was not going to die completely on its own, they removed the coals and dumped them into a snowbank.

It’s entirely possible that this is somehow operator error. I don’t know if some combination of the low temperatures today or something else made this different than all of the other times we have had fires. All I know is that tonight something went very wrong.

I don’t love my local dealer as they have been dismissive a couple of times when I have had questions after the sale, and since I made the mistake of buying a VC, I can’t contact the manufacturer.

I understand some people on here are more skilled than I am at using this stove and using stoves in general. Like I said, this could be operator error. It’s just interesting to me that nobody else I know who has a stove seems to experience these sorts of problems.

Sorry for the rant. All that I can say is that the whole experience scared the **** out of me, and I won’t be using it again.

 

[skb31]

This is an over fire and they can be scary. I would get the stove inspected before using it again if you reach that point. There’s a couple things that stand out in your post but you might not be looking for that kind of feedback at the moment.

 

[all night moe]

oak takes 3yrs to season, in many parts of the country. It may be in the Midwest, you are able to achieve faster drying times with above average winds?

If not seasoned below 20% moisture content, you most likely had creosol build up in the stove pipe and chimney. Probably a bit further up from the stove where flue temps are a little cooler. Being really cold out increases draft. I would think that the flames shot up the flue upon your opening of the bypass damper, igniting the creosol. This would also increase draft, burning everything available, ass fast as possible.

 

[manofstihl]

This is an over fire and they can be scary. I would get the stove inspected before using it again if you reach that point. There’s a couple things that stand out in your post but you might not be looking for that kind of feedback at the moment.

Thank you. Sincerely. I wasn’t last night, but I think I can deal with it today. What did I do wrong?

To be honest, I think, if I buy another stove, I just need something simpler.

oak takes 3yrs to season, in many parts of the country. It may be in the Midwest, you are able to achieve faster drying times with above average winds?

If not seasoned below 20% moisture content, you most likely had creosol build up in the stove pipe and chimney. Probably a bit further up from the stove where flue temps are a little cooler. Being really cold out increases draft. I would think that the flames shot up the flue upon your opening of the bypass damper, igniting the creosol. This would also increase draft, burning everything available, ass fast as possible.

The oak was a fraction of the maple—maybe 10 to 15 percent.

When I have measured in the past (I didn’t measure the load that I placed into the stove), my measurements were—if I recall correctly—around 12 to 14 percent on the maple and slightly higher on the oak, maybe 13 to 16. This is measured from the middle of a fresh split.

I’m not saying it wasn’t an issue with the wood, but I am very serious about splitting and seasoning in an adequate amount of time. The wood sits in my backyard where it is exposed to lots of wind and sunshine. I don’t tarp it until autumn, and I only tarp what I need for a season.

 

[manofstihl]

Couple notes:

I asked about creosote buildup when I had sweeps come after each of the past two years. Neither noticed any.

I went outside to see if I had flames coming from the chimney when I thought that I might be having a problem start. At no point was I able to see any. I don’t know if that makes a difference, but I have read that people often see flames when there is a chimney fire.

 

[all night moe]

the oak, maybe 13 to 16. This is measured from the middle of a fresh split.

Should also be up to room temp and the prongs parallel with the grain. Just to be clear.

it is exposed to lots of wind and sunshine. I don’t tarp it until autumn, and I only tarp what I need for a season

This is good. The wind is the major drying factor. When you do tarp, try just top covering your stacks, or pile. I realize many, who live in windy areas, can get away without stacking. Also elevate off the ground on pallets. Helps with complete air flow and separating from ground moisture.

Again, just for clarity.

 

[stoveliker]

Couple notes:

I asked about creosote buildup when I had sweeps come after each of the past two years. Neither noticed any.

I went outside to see if I had flames coming from the chimney when I thought that I might be having a problem start. At no point was I able to see any. I don’t know if that makes a difference, but I have read that people often see flames when there is a chimney fire.

One "vein" of wet wood in your stacks of only 2 or 3 stove loads of wood that's too wet and that is turned down much can mess up a chimney already.

On the other hand, maybe it was all dry and that is what caused an overfire; it taking off quicker than you could dampen it down, especially with it being colder than most times you've burned (I think), which increases draft.

I don't know the ins and outs of the operation of your stove, so I'll leave advice on that to others.

 

[skb31]

With the information you’ve provided I don’t think you had a chimney fire. I think you over fired your stove. Many of us have done this at some point and I certainly I did with my previous stove.

I do not have a dauntless but I do have a VC encore. Here’s a couple things I noticed and hopefully the smarter people here will also chime in.

Colder temps outside will create more draft because the temperature difference is greater. I need more control of the air when it’s cold and if it’s also windy the draft is noticeably stronger.

You reloaded on a thick bed of hot coals and used smaller pieces directly on the bed of coals to aid in keeping the glass clean. The state of the glass seems to be an area of concern for VC owners because they tend to get dirty. For me the glass is not indicative of how well the stove is running. I run my stove off referencing the cat chamber and flue temps. If they are good then I am good. When the stove is cold you can easily clean the glass using damp paper towels dipped in cold ashes from your firebox. Skip the smaller pieces in the future and load big splits directly onto the hot coals.

You waited roughly 10 minutes to engage the bypass damper. On a hot reload I engage the bypass damper immediately per my instructions. The fuel doesn’t need to be fully ignited prior to engaging the damper. I manage the temps with the primary air control once the damper is closed and the temps come up,

You opened the bypass damper when the flames began “dying on and off.” I’m not sure how quickly you closed the damper again after this and I’m not sure what your temps were at the time but this contributed to another rapid ignition of your fuel. Primary air was likely the go to if you wanted to adjust the stove at this point because these VCs can look to be smoldering when they’re actually running well. Cat and flue temps tell the real story.

So increased draft, small splits on hot coals with a larger fuel load in top, waiting to close the damper, and then opening the damper under these circumstances led to what appears to be an over fire. If your stove has unregulated secondary air you can take steps to restrict it when it runs hot, or use a key damper to limit draft.

On a side note, I have no idea what a Chimfex stick does when used in an over fire. I have never used one so maybe someone else knows but I think they are used in updraft mode to flood the chimney with CO2 when there’s a chimney fire.

I’m glad it worked out ok for you. Get your system inspected as glowing parts can get warped. There are simpler and easier stoves you can buy. No one would blame you one bit if you moved on from this one and onto something else. There’s plenty of advice on this forum for which brands and types to consider.

 

[all night moe]

With the information you’ve provided I don’t think you had a chimney fire. I think you over fired your stove. Many of us have done this at some point and I certainly I did with my previous stove.

I do not have a dauntless but I do have a VC encore. Here’s a couple things I noticed and hopefully the smarter people here will also chime in.

Colder temps outside will create more draft because the temperature difference is greater. I need more control of the air when it’s cold and if it’s also windy the draft is noticeably stronger.

You reloaded on a thick bed of hot coals and used smaller pieces directly on the bed of coals to aid in keeping the glass clean. The state of the glass seems to be an area of concern for VC owners because they tend to get dirty. For me the glass is not indicative of how well the stove is running. I run my stove off referencing the cat chamber and flue temps. If they are good then I am good. When the stove is cold you can easily clean the glass using damp paper towels dipped in cold ashes from your firebox. Skip the smaller pieces in the future and load big splits directly onto the hot coals.

You waited roughly 10 minutes to engage the bypass damper. On a hot reload I engage the bypass damper immediately per my instructions. The fuel doesn’t need to be fully ignited prior to engaging the damper. I manage the temps with the primary air control once the damper is closed and the temps come up,

You opened the bypass damper when the flames began “dying on and off.” I’m not sure how quickly you closed the damper again after this and I’m not sure what your temps were at the time but this contributed to another rapid ignition of your fuel. Primary air was likely the go to if you wanted to adjust the stove at this point because these VCs can look to be smoldering when they’re actually running well. Cat and flue temps tell the real story.

So increased draft, small splits on hot coals with a larger fuel load in top, waiting to close the damper, and then opening the damper under these circumstances led to what appears to be an over fire. If your stove has unregulated secondary air you can take steps to restrict it when it runs hot, or use a key damper to limit draft.

On a side note, I have no idea what a Chimfex stick does when used in an over fire. I have never used one so maybe someone else knows but I think they are used in updraft mode to flood the chimney with CO2 when there’s a chimney fire.

I’m glad it worked out ok for you. Get your system inspected as glowing parts can get warped. There are simpler and easier stoves you can buy. No one would blame you one bit if you moved on from this one and onto something else. There’s plenty of advice on this forum for which brands and types to consider.

Wow, very well said.

 

[manofstihl]

Colder temps outside will create more draft because the temperature difference is greater. I need more control of the air when it’s cold and if it’s also windy the draft is noticeably stronger.

Lesson learned the hard way there.

You reloaded on a thick bed of hot coals and used smaller pieces directly on the bed of coals to aid in keeping the glass clean. The state of the glass seems to be an area of concern for VC owners because they tend to get dirty. For me the glass is not indicative of how well the stove is running. I run my stove off referencing the cat chamber and flue temps. If they are good then I am good. When the stove is cold you can easily clean the glass using damp paper towels dipped in cold ashes from your firebox. Skip the smaller pieces in the future and load big splits directly onto the hot coals.

We are talking literally two tiny pieces of kindling laid perpendicular to the larger splits. These are maybe the same circumference as a dime. Is that really making a difference? Not trying to be hostile here, and I won't do it again, but that seems like such a small detail.

I've been doing that for a couple years because it seems to reduce the amount of fouling on the glass. The glass on the Dauntless gets so dirty that it takes me 15 to 20 minutes hard scrubbing with ashes to remove the carbon or whatever it is.

It's astounding to me that my handful of friends with stoves clean their glass a few times a year at most. Some of these guys are not nearly as picky as I am about splitting and drying and moisture content. One of them bucks in winter the year before and splits maybe a month before burning season.

You waited roughly 10 minutes to engage the bypass damper. On a hot reload I engage the bypass damper immediately per my instructions. The fuel doesn’t need to be fully ignited prior to engaging the damper. I manage the temps with the primary air control once the damper is closed and the temps come up,

I don't know the exact time frame, but your point stands that I did not close the bypass damper immediately. In the past when I have done that immediately, I have gotten completely opaque glass.

You opened the bypass damper when the flames began “dying on and off.” I’m not sure how quickly you closed the damper again after this and I’m not sure what your temps were at the time but this contributed to another rapid ignition of your fuel. Primary air was likely the go to if you wanted to adjust the stove at this point because these VCs can look to be smoldering when they’re actually running well. Cat and flue temps tell the real story.

That blowtorch sound persisting was starting to scare me pretty badly. I had never heard it for that long before. I thought that I might have a chimney fire.

If I recall correctly, I didn't close the damper again because I was restricting the primary air at that point. Maybe I should have. Shortly after, I saw the overfiring on the inner pipe of the double-wall stovepipe. Then I shut the primary air off.

@skb31 I appreciate the help. Any frustration in the post is not intended toward you.

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Like I said, I do not think this is the stove for me. When I bought it, I was looking for a Jotul, but they were really hard to find at that time. It is going to prove to be a costly mistake on my part. I don't trust the Dauntless.

 

[brenndatomu]

Yup, loaded on too many hot coals...should have let them burn down a little more before loading.
Can turn air down faster when loading on plenty of hot coals too...keep the firebox from being completely engulfed in flames. (If fire is likely gonna try to take off on you, gotta start damping down earlier) if you damp down too early and the fire stalls, you can always open it back up some until things settle in, much harder to rein in once it really takes off though

 

[skb31]

Don’t worry about sounding frustrated. I read and write text as plainly as possible so it’s a two way a street when it comes to communication this way.

I don’t think two dowel size pieces would make much difference if you had closed the damper right away. The irritation with the opaque class is understandable. The blowtorch sound is something most of us have experienced. I’m curious if you had a temp reading from the cat chamber at that point? Or if using the factory supplied probe, was it in operational range?

It now makes sense why you had glowing parts if you left it damper up with a significant fuel load in the stove.

Lastly, there’s a couple ways to consider whether how costly mistake this actually was. Here’s one way. Your investment has clearly shown you what you expect out of a wood stove and its manufacturer. You are far from any worst case scenario up to this point and if you need to replace the stove for peace of mind then so be it.

 

[a59cheffy]

manofstihl​

I am so sorry this happened to you. It's scary stuff. I had a chimney fire during the first season with my Dauntless. Stopped using it and got the stove and chimney inspected. With a $6200 investment in stove and install I was determined to figure out how to make this stove work. Thanks to this forum and experience I have come to love this stove.

It is my understanding and experience that when the CAT overfires and causes the blow torch sound it's because there is too much out gassing and smoke from the burning wood. Having it cold outside increased the draft which made the burning gasses reach much further up into your chimney. Causing more draft and hotter temps at the stove. By closing the air down that created more smoke for the over- fired CAT to burn. I can't tell you what caused the extreme out gassing initially, I can only guess at the condition of your wood. You would know better than I.

Once I didn't close the ash pan tight enough and that caused a really hot fire and overfiring, I had left the room and came back to a roaring hot fire. Luckily I figured it out quick,

Since learning how to use this stove I have had no problems with the glass on my doors. I burn pretty hot (450 -600 degrees) and it helps tremendously keeping it clean. I just wipe if there is build up with a dry paper towel. Comes right off.

I don't blame you one bit if you ditch this stove. From what I have read on these forums all the downdraft and updraft models of CAT stoves are not without their own problems. Some are easier for sure.

 

[bullittman281]

Howdy,
Couple of thoughts...
There is no arguing that these stoves are fussy, putting it mildly. I run mine sans a cat so my experience isn't exactly the same as those with the cat. I've found the secondary burner to be quite noisy. If I can't hear mine, and there is active wood in it, its smoking hard. Period. The manual does a huge disservice to the owners of these. I can have one tiny stick on the coal bed burning and it makes it rumble. There is NO way a single, small piece of wood is over firing the stove. These things make some noise.

Second thing I've observed. With the damper open and the stove hot, it drafts STRONG. There is nothing stopping the stack from sucking fire. Turning down the air control doesn't help. There are 2 paths for air to enter the firebox. The air wash on the glass and the secondary air for the secondary burner. There is no control over secondary air supply, only the primary. When the bypass is closed, the secondary air is forced only though the secondary burner and out the bottom back. With the damper open it can escape the bottom of the burner and add additional air to the fire. Closing the primary only further encourages this. Pretty much once hot the bypass needs to be closed, or things go wild. I haven't had anything glow, but this stove flat gets after it with the bypass open. Again, the de-structions for running this stove are incomplete and don't do anybody involved any justice. The stove is hard to run.

The last thing I'm running into is temperature monitoring. Cheap surface thermometers are trash, at best. I found mine reads more that 150* high. These stoves want to run warm. Trying to keep mine at what turned out to be less than 450 MAX lead to burn problems and black glass. When it runs well, the glass stays OK-ish and can be cleaned off easy enough. I still give mine an F+ or D- for the glass but its not completely unbearable. Trying to burn it too cold with no fire in the fire box leads to black glass, smoke and back puffing. The needs to be some flame, and at least without the cat, a rumble.

Ultimately your call on its final fate, but I enjoy mine now that I can run it. They can burn clean and look great doing in.
After that thing got as hot as it surly did, make sure everything still fits and seals. I can see an air leak being disastrous, especially the ash door. That would turn it into a forge and melt things!

Good luck!!

 

[Woodsplitter67]

One of the things Id like to touch on is the blowtorch sound.

Om not sure why this bothers people so much and people feel the need to panic. I have read this on a number of thread's and people feel the need to do something, and that something leads to the stove running away.

The sound in the back of the stove is absolutely nothing to be afraid of. Normally you don't hear anything, but sometimes people do something wrong and you'll start getting that sound. So what is this sound. Its the sound of ALOT of smoke going through the combuster and the combuster is getting hot.. like really hot, and the stove will start to draft harder. So what should you do.. Absolutely nothing the stove is fine.. its just going to run hot in the back end for a little bit until the offgassing stop.. Smoke is what actually is burning in the combuster so once the majority of the offgassing passes the catalyst will dip down into the normal range.

The worst thing anyone can do is actually turn the air up and open up the damper.. That turns the firebox into a complete flaming mess and an uncontrollable fire.. making things worse your dumping wayyyy to much heat up the stovepipe and making waaaayyy to much draft and at that poing trying to close the damper will make the cat go super nuclear.

If you guys hear the blowtorch sound.. STOP Panicking and just watch the stove and monitor the flue temp.. the temperature spike will pass before the stovepipe gets to hot. Just let it burn, the worst thing that will happen is you will take some life out of the catalyst.. THATS IT..

I think a month ago I loaded the stove before bed for my overnight burn and my coal bed wasn't as thick as normal. I loaded the stove full and a couple hours later the entire box started to offgass and my catalyst rocketed past 1730.. guess what I did.. Absolutely nothing .. and the catalyst dropped to 1400.. If I would have opened the damper... The fire department would have been hanging out at my pad for a little while with burning logs thrown in the driveway.. instead I let the burn run its course and then.. continued burning for the rest of the winter

 

[all night moe]

One of the things Id like to touch on is the blowtorch sound.

Om not sure why this bothers people so much and people feel the need to panic. I have read this on a number of thread's and people feel the need to do something, and that something leads to the stove running away.

The sound in the back of the stove is absolutely nothing to be afraid of. Normally you don't hear anything, but sometimes people do something wrong and you'll start getting that sound. So what is this sound. Its the sound of ALOT of smoke going through the combuster and the combuster is getting hot.. like really hot, and the stove will start to draft harder. So what should you do.. Absolutely nothing the stove is fine.. its just going to run hot in the back end for a little bit until the offgassing stop.. Smoke is what actually is burning in the combuster so once the majority of the offgassing passes the catalyst will dip down into the normal range.

My old school "dragon breath" wood furnace can do the same. It doesn't have a combuster but a vertical chamber on the back wall of the furnace. With the bypass closed, exhaust exits at the bottom of that chamber. As of late, I have been pushing coals to the back and covering the opening with them. The coals start getting excited and you can here the rush of air. This chamber has a secondary heated air feed. When I start throwing wood in, and it starts off gassing, that sound becomes a roar. I call it the dragon's breath. It's the combustion of those gasses, and Iove it.

It's a primitive system from the mid 70s but it works. Company started in '76 I believe. Mine is dated '78.

 

[manofstihl]

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I don’t think two dowel size pieces would make much difference if you had closed the damper right away. The irritation with the opaque class is understandable. The blowtorch sound is something most of us have experienced. I’m curious if you had a temp reading from the cat chamber at that point? Or if using the factory supplied probe, was it in operational range?

It was around the middle of the probe range when I closed the damper. I honestly don't remember where it was when I reopened it.

One of the things Id like to touch on is the blowtorch sound.

Om not sure why this bothers people so much and people feel the need to panic. I have read this on a number of thread's and people feel the need to do something, and that something leads to the stove running away.

It could possibly be that the manual states, "If you hear a rumbling or a roaring noise (like a propane torch) from the stove, that is a sign that the stove is over-firing" [emphasis mine]. It's on page 14. There is zero mention of that being a normal operating condition anywhere in the manual.

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I think after reading through the thread that Woodsplitter's description of what happened is essentially accurate.

The worst thing anyone can do is actually turn the air up and open up the damper.. That turns the firebox into a complete flaming mess and an uncontrollable fire.. making things worse your dumping wayyyy to much heat up the stovepipe and making waaaayyy to much draft and at that poing trying to close the damper will make the cat go super nuclear.

My conclusions:

• My wood was dry and seasoned. This is the least likely explanation.
• My coal bed was slightly larger than normal, but not significantly so. This may have played a minor contributing factor.
• The temperatures that night were extremely low. This likely played a contributing factor.
• My decision to wait to close the damper after a hot reload and then open the damper at that point in the burn led to the overfiring. At that point, there was probably nothing that I could have done differently than what I did to get it back under control.

Having a stove is something that my family and I really enjoy. It's going to need to be a different one than this one, though, and I'll eventually start another thread to that end. I am planning to buy something that is simpler and less efficient.

 

[all night moe]

I am planning to buy something that is simpler and less efficient.

No need to sacrifice efficiency.
Plenty of great burning stoves on the market.

 

[Woodsplitter67]

It was around the middle of the probe range when I closed the damper. I honestly don't remember where it was when I reopened it.


It could possibly be that the manual states, "If you hear a rumbling or a roaring noise (like a propane torch) from the stove, that is a sign that the stove is over-firing" [emphasis mine]. It's on page 14. There is zero mention of that being a normal operating condition anywhere in the manual.

---

I think after reading through the thread that Woodsplitter's description of what happened is essentially accurate.


My conclusions:

• My wood was dry and seasoned. This is the least likely explanation.
• My coal bed was slightly larger than normal, but not significantly so. This may have played a minor contributing factor.
• The temperatures that night were extremely low. This likely played a contributing factor.
• My decision to wait to close the damper after a hot reload and then open the damper at that point in the burn led to the overfiring. At that point, there was probably nothing that I could have done differently than what I did to get it back under control.

Having a stove is something that my family and I really enjoy. It's going to need to be a different one than this one, though, and I'll eventually start another thread to that end. I am planning to buy something that is simpler and less efficient.

So to clarify.. I never stated that the blowtorch sound was a NORMAL operating condition. What Im saying to you and everyone else is dont panic and just leave the stove alone. The sound is your stove/wood is going through alot of offgassing and that is what is making the sound. If you leave the stove alone the offgassing phase doesn't last long at all and the temperature of the catalyst will drop well before the stovepipe overheats

If you want to get rid of the stove.. that's fine, Im not trying to talk you into keeping it.. and I know what the manual says as I have an encore myself. What im saying to everyone who reads this is even though your manual says this is bad.. just let it run its course.. because nothing bad will happen and if you leave the stove alone the world will not spontaneously combust.

Again my cat went to over 1730 and I did nothing.. and nothing happened, I woke up the next morning.. the sun came up.. birds chirped.. everyone went to work and school and life went on..

 

[skb31]

It was around the middle of the probe range when I closed the damper. I honestly don't remember where it was when I reopened it.

No worries, just curious. Many of us rely on our digital gauges to manage these stoves which to me suggests they’re not as user friendly as we’d like. All you can do is make the best choice for yourself going forward. You gained a bunch of knowledge from your experience and so did some other people who will read this.