I am having trouble controlling the burn of my VC intrepid. I opted not to get the cat and have it installed with stainless liner in two story chimney. Starting end of the season last year I was often unable to control the burn using the air control. The damper will be closed and the air control all the way to the negative and the fire can take off. This occurs regularly after cleaning the ash from the firebox. I regain some control by stuffing 2 or 3 small holes at the bottom of the refractory burn plate with ash, but it seems at random it can just take off. In addition, this year there is a noticeable whistle with the damper is shut. I was planning on replacing the ashpan and damper gasket then stuffing the small holes with insulation to see if this helps. figured though maybe someone with more experience may have a better idea. thanks
vermont castings intrepid flexburn trouble controlling burn
- Thread starter jstol
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I don't know your stove, but have a few suggestions to get some info that may help pinpoint the cause.
How tall is your chimney? Too tall may mean too much draft, and might make a need for a damper.
Have you done dollar bill tests on gaskets, including the ash door? Air leaking in from below will easily make it run away.
How tall is your chimney? Too tall may mean too much draft, and might make a need for a damper.
Have you done dollar bill tests on gaskets, including the ash door? Air leaking in from below will easily make it run away.
the chimney is 22 or so feet. I have read the whistle could be because of excess draft however the whistle was not there the last two seasons. the stainless flexible piping was also new though and has likely constricted since due to creosote buildup. I don't know if this could increase the draft. I don't know the dollar bill test but I have taken a stick of incense and drug it around the doors of the stove. I did see smoke getting sucked in around the joint where my stove pipe meets the flue collar. I could try sealing that up as well with some insulation or high temp caulking. is that a good idea? probably also a mess.
If you suspect constriction by creosote, you should stop burning as that would be a chimney fire waiting to happen. I don't think that is going on here, because it would decrease draft.
The whistle may be excess but doesn't necessarily have to be. 22 ft is on the tall side, but not crazy.
The dollar bill test is to put a bill between the door and body, close the door, and pull it out. It should have some resistance. Cold stove, of course.
Sealing the flue should not be necessary. Leaking in there decreases draft applied to your stove anyway. If the pieces fit snugly, it should be fine.
Is your wood much drier this year?
The whistle may be excess but doesn't necessarily have to be. 22 ft is on the tall side, but not crazy.
The dollar bill test is to put a bill between the door and body, close the door, and pull it out. It should have some resistance. Cold stove, of course.
Sealing the flue should not be necessary. Leaking in there decreases draft applied to your stove anyway. If the pieces fit snugly, it should be fine.
Is your wood much drier this year?
I’m starting to see a trend with these new VC flex burn stoves being used as non cats but I could be wrong. Maybe taller chimneys would benefit with a cat since it helps restrict the draft somewhat?
Which model Intrepid is this?
Is there a key damper in the stovepipe to help reduce draft?
Welcome to the club.
I have a VC Dauntless. Basically the same stove as you just slightly larger. Mine is at a weekend camp, and I just installed it right before fall hit. So I hadnt had the chance to really learn it before I needed to use it. I did some smaller short burns to start, then larger/longer ones and have done about 6 overnight burns and a few all weekend burns.
Im learning to control the stove,.....and I'm learning that the stove controls me.
Im totally new to wood burning stoves, I should mention. Im sure some of the lifelong stove burners in here would operate our stoves much differently that we do.
Overall though, Im a little salty about my Dauntless. For what I paid for it, plus the pipe etc, I guess Im up to about $4500? I did the install myself. I have a 15' total run.
I rambled on with my experiences in another thread but..
The air control on these can be kinda random. Outside temps, wood type, and how it is packed in the stove, and your air control all seem like factors you can use to control the stove, to some degree. I DO NOT understand the logic behind having the tiny holes for secondary air flow so low where they will likely get clogged by ash. You may be hearing a whistle coming from there. If you open your damper, wait a bit then slowly crack the top hatch - do you see flames RUSHING up the chimney? I do. Not always but if there is enough wood in there ablaze then I will see this. Be careful checking on your wood when you have the stove fully packed. I did this last weekend because I wanted to see after 30 minutes of having air control on medium what was going on with the wood. Me opening the door caused the slowly burning wood to suddenly erupt and a ball of fire rushed out and up towards my roof. Im not joking. I burned most of the hair on my hand and part of my arm. I then reached for my hair to make sure I wasnt more bald.
So last weekend, Saturday morning I woke up to a COLD house because we ran out of oil and normally I set that to like 60 however all other weekends I normally wake up to the living room (area next to stove) and the area the stove is in fairly warmish, around maybe 65-68? It was really cold outside, so the stove just wasnt keeping up. And I think I burned too fast thinking it was going to be cold outside and to have a warm morning I better set this thing to 5th from the lowest setting which is like 4 from highest as I think these things have like 9 clicks in them.
Well that saturday that I woke up to a cold house, I proceeded to load about 3-4 on the smaller side of medium splits inside the stove. I had some coals but had to pop in some cardboard to get flames going to get the stove back on fire. I left the damper open and the air control on highest. I knew it was going to be warm and sunny that day (65f) so once I felt like I was getting good heat from the stove I shut it down. I left for about an hour to do stuff, and then I heard my daughter yell and then she came over and said "whats that SMELL!", oh shoot - I smell it now. It's the smell you get when you are burning in your new stove. The smell that I shouldnt be getting anymore unless I hit a new all time high temp. I rushed over to the stove. 700 degrees. The stove was BLAZING! The entire window (the areas you could see through the thick black coating because this stove is designed piss poorly), was FULL of fire. I double checked that everything was set to where I left it, damper closed - check, air control on the lowest setting - check.
WTF. Now what? So I figured I would post on here, and wait for my favorite mod to respond. Begreen basically said keep calm it will settle eventually. And sure enough about 20 minutes or so later it QUICKLY went down in temps. I dont know if it was because I went over to the air control and moved it to the highest setting then back to the lowest setting thinking I was 'resetting' it, or just because it ran out of fuel quickly burning at that rate. I then opted to let it burn down at that point, but then the damage was already done. My mind was a bit more frail, my hair more gray (what didnt burn), and my room was now 78 degrees.
Did my son mess with it, because it was cold and then he saw it blazing and turned it back down? No one fessed up to it, but when dad is running around screaming those moments of honesty come usually a bit delayed. I honestly dont think he did though. I taught them to be afraid or being near the stove. I tried to show my wife how to operate it, and she said based on what Ive endured trying to control this she is afraid she will end up overfiring it and damaging it so she doesnt want to mess with it.
A fully packed stove, I will leave the damper open and air control on high for about 15 minutes or so after packing. Then I will lower the air control to about mid way after shutting down the damper. Many times I then need to lower it again, or raise it back up a bit depending on how cold it is and how well the wood type and the stove are burning the wood. A fully packed stove, I dont think Ive had get to high temps even with the air control fully open, unless Ive been burning it for a few hours. I will admit to constantly peaking at the wood inside to check how things are burning, especially when I only load about mid way. I dont know if smaller loads are recommended or if you are always supposed to load it fully. I like to see some flames though, so I load it mid way usually and then try to control the heat using air control. When I do this though, I am constantly messing with the air control. I never touch it more than once every 30-60 minutes because I want to see what happens when I change things. I often just let it go for hours without touching it as well to also see what will happen through the burn cycles, unless of course it starts getting to 650 then I will lower it quite a bit to stave off overburn risk.
I can heat the stove up fairly quickly with smaller splits and only like 4 inside and kinda criss crossing them. Even if I shut everything down, I will usually still see some flames wicking. However, if I have a fully loaded stove, even a modest amount of air open, I rarely see flames.
The stove does feel like it is either ON or OFF, the in between is a challenging thing to stay in. I too do not have the cat installed. I wanted to burn at least through a month or two of winter before getting the cat so that I could compare my experience. At that point it will be toward the tail end of winter heading into spring, and I will have similar burns with similar temps to what I had prior to installing the cat and will know how well it works (or doesnt).
Oh I should mention it was REALLY windy the day I had the 700 degree blaze. So that may have contributed to things as well. Who knows.
Is your glass always dark? Mine is. The glass gets cleaned by the heat/fire in the middle and lower sides but never the upper sides, it's always dark with thick black soot. I bet I could scrap about a table spoon of crap off each door. And I am burning wood that is generally around 17-18% MC, so well below the 'well seasoned' recommendation of less than 20%.
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there was a drought in Massachusetts this summer while it was drying so it could be a little drier but probably not that much Thank you, Ill try the dollar test. I have tried to determine where the whistle is coming from but can not pin it down.
model 2115. this will be the third winter I have been using it. problems started at the end of last year. there is no key damper unfortunately
I dont know if the dollar bill test is super viable for a complete check. On my dauntless I noticed on the door that creosote was like dripping onto the gasket that isnt covered by the door. It then firmed up to this hard mass, that I could chip away, but it seemed to have seeped into the gasket making it hard as a rock. I was hopeful that it didnt impact my ability to seal the door. This by the way is on a new stove, and I dont know if this is normal or poor design/abnormal. I did a 100 dollar bill test and of course I could pull the bill out, but I didnt pull very hard seeing as it was a 100 dollar bill. I normally never have cash on me, but I was at the casino the night prior.
I think the best idea would be to get something the same thickness as a dollar bill but much more narrow and much stronger, that would allow for a more micro check and a tougher tug without ripping the test media. What exactly to use I am not sure. A thin tin would surely slide much more easily than a cloth dollar bill.
This is essentially my experience at the end of last year and now the beginning of this year. My glass is always dark now but this and the uncontrollable burn were not aspects of the stove for my first 1.5 years of operation. This weekend I plan on 1. stuffing the holes in the refractory burn plate with insulation then firing it to see if I have greater burn control-listen for the whistle. If this does not change anything Im going to replace the damper and ash drawer gaskets. Ill post with the results or lack there of. thanks all.Welcome to the club.
Mine is at a weekend camp, and I just installed it right before fall hit. So I hadnt had the chance to really learn it before I needed to use it. I did some smaller short burns to start, then larger/longer ones and have done about 6 overnight burns and a few all weekend burns.
Im learning to control the stove,.....and I'm learning that the stove controls me.
Im totally new to wood burning stoves, I should mention. Im sure some of the lifelong stove burners in here would operate our stoves much differently that we do.
Overall though, Im a little salty about my Dauntless. For what I paid for it, plus the pipe etc, I guess Im up to about $4500? I did the install myself. I have a 15' total run.
I rambled on with my experiences in another thread but..
The air control on these can be kinda random. Outside temps, wood type, and how it is packed in the stove, and your air control all seem like factors you can use to control the stove, to some degree. I DO NOT understand the logic behind having the tiny holes for secondary air flow so low where they will likely get clogged by ash. You may be hearing a whistle coming from there. If you open your damper, wait a bit then slowly crack the top hatch - do you see flames RUSHING up the chimney? I do. Not always but if there is enough wood in there ablaze then I will see this. Be careful checking on your wood when you have the stove fully packed. I did this last weekend because I wanted to see after 30 minutes of having air control on medium what was going on with the wood. Me opening the door caused the slowly burning wood to suddenly erupt and a ball of fire rushed out and up towards my roof. Im not joking. I burned most of the hair on my hand and part of my arm. I then reached for my hair to make sure I wasnt more bald.
So last weekend, Saturday morning I woke up to a COLD house because we ran out of oil and normally I set that to like 60 however all other weekends I normally wake up to the living room (area next to stove) and the area the stove is in fairly warmish, around maybe 65-68? It was really cold outside, so the stove just wasnt keeping up. And I think I burned too fast thinking it was going to be cold outside and to have a warm morning I better set this thing to 5th from the lowest setting which is like 4 from highest as I think these things have like 9 clicks in them.
Well that saturday that I woke up to a cold house, I proceeded to load about 3-4 on the smaller side of medium splits inside the stove. I had some coals but had to pop in some cardboard to get flames going to get the stove back on fire. I left the damper open and the air control on highest. I knew it was going to be warm and sunny that day (65f) so once I felt like I was getting good heat from the stove I shut it down. I left for about an hour to do stuff, and then I heard my daughter yell and then she came over and said "whats that SMELL!", oh shoot - I smell it now. It's the smell you get when you are burning in your new stove. The smell that I shouldnt be getting anymore unless I hit a new all time high temp. I rushed over to the stove. 700 degrees. The stove was BLAZING! The entire window (the areas you could see through the thick black coating because this stove is designed piss poorly), was FULL of fire. I double checked that everything was set to where I left it, damper closed - check, air control on the lowest setting - check.
WTF. Now what? So I figured I would post on here, and wait for my favorite mod to respond. Begreen basically said keep calm it will settle eventually. And sure enough about 20 minutes or so later it QUICKLY went down in temps. I dont know if it was because I went over to the air control and moved it to the highest setting then back to the lowest setting thinking I was 'resetting' it, or just because it ran out of fuel quickly burning at that rate. I then opted to let it burn down at that point, but then the damage was already done. My mind was a bit more frail, my hair more gray (what didnt burn), and my room was now 78 degrees.
Did my son mess with it, because it was cold and then he saw it blazing and turned it back down? No one fessed up to it, but when dad is running around screaming those moments of honesty come usually a bit delayed. I honestly dont think he did though. I taught them to be afraid or being near the stove. I tried to show my wife how to operate it, and she said based on what Ive endured trying to control this she is afraid she will end up overfiring it and damaging it so she doesnt want to mess with it.
A fully packed stove, I will leave the damper open and air control on high for about 15 minutes or so after packing. Then I will lower the air control to about mid way after shutting down the damper. Many times I then need to lower it again, or raise it back up a bit depending on how cold it is and how well the wood type and the stove are burning the wood. A fully packed stove, I dont think Ive had get to high temps even with the air control fully open, unless Ive been burning it for a few hours. I will admit to constantly peaking at the wood inside to check how things are burning, especially when I only load about mid way. I dont know if smaller loads are recommended or if you are always supposed to load it fully. I like to see some flames though, so I load it mid way usually and then try to control the heat using air control. When I do this though, I am constantly messing with the air control. I never touch it more than once every 30-60 minutes because I want to see what happens when I change things. I often just let it go for hours without touching it as well to also see what will happen through the burn cycles, unless of course it starts getting to 650 then I will lower it quite a bit to stave off overburn risk.
I can heat the stove up fairly quickly with smaller splits and only like 4 inside and kinda criss crossing them. Even if I shut everything down, I will usually still see some flames wicking. However, if I have a fully loaded stove, even a modest amount of air open, I rarely see flames.
The stove does feel like it is either ON or OFF, the in between is a challenging thing to stay in. I too do not have the cat installed. I wanted to burn at least through a month or two of winter before getting the cat so that I could compare my experience. At that point it will be toward the tail end of winter heading into spring, and I will have similar burns with similar temps to what I had prior to installing the cat and will know how well it works (or doesnt).
Oh I should mention it was REALLY windy the day I had the 700 degree blaze. So that may have contributed to things as well. Who knows.
Is your glass always dark? Mine is. The glass gets cleaned by the heat/fire in the middle and lower sides but never the upper sides, it's always dark with thick black soot. I bet I could scrap about a table spoon of crap off each door. And I am burning wood that is generally around 17-18% MC, so well below the 'well seasoned' recommendation of less than 20%.
In one corner of the gasket for the ash drawer I believe this is happening. no noticeable smoke was getting sucked in there though. I replaced the gridle gasket last season and it was not hard. Ill probably just do this one soon.
Ripping a one dollar bill is a small investment to ascertain a gasket is still working well.
If the glass is always dark (evenly?) and you have good draft, that could mean cold air is leaking in near the glass.
I don't know how the glass is mounted in the door on this stove, but see if it is still ok. On a cold stove,.open the door and out your hands flat on both sodes of the glass. See if you can move.it in the door frame. (Be careful for accidentally lifting the door off its hinges, if possible...)
@GrumpyDad if your window is always dark, you could have insufficient draft, leading to too slow a burn, mucking up the firebox (and chimney).
With 22ft here I doubt that's the case. Unless the chimney is restricted by deposits (or remnant squirrel nests...)
If the glass is always dark (evenly?) and you have good draft, that could mean cold air is leaking in near the glass.
I don't know how the glass is mounted in the door on this stove, but see if it is still ok. On a cold stove,.open the door and out your hands flat on both sodes of the glass. See if you can move.it in the door frame. (Be careful for accidentally lifting the door off its hinges, if possible...)
@GrumpyDad if your window is always dark, you could have insufficient draft, leading to too slow a burn, mucking up the firebox (and chimney).
With 22ft here I doubt that's the case. Unless the chimney is restricted by deposits (or remnant squirrel nests...)
I dont think I have a draft issue. When I open the damper and open the top hatch, fire rushes up through the damper like someone has a flamethrower under the wood. If Im on secondary and have the doors closed, I can hear air rushing through that chamber.
The only problem I ever had with draft was walking into a cold house at around 49 degrees with the outside temps at 49 degrees, I started the furnace up, and then the fireplace in the other room, then I tried lighting a bottom up fire. And then smoke billowed out of all the doors, fresh air intake, ash drawer, everywhere. However I have tested all of those areas when I first got the stove prior to using, and they did pass the dollar bill test.
@GrumpyDad
Well, I've been told here over and over again that tube stoves have such a fantastic fireview, opposite to my cat stove (that I enjoy watching burn). Ergo, something is wrong when your stove gets mucked up on the inside.
Well, I've been told here over and over again that tube stoves have such a fantastic fireview, opposite to my cat stove (that I enjoy watching burn). Ergo, something is wrong when your stove gets mucked up on the inside.
I thought itnhad both tubes and a cat, the latter if which you didn't install.
If you have neither, you are likely mucking up your chimney big time now, considering the creosote deposits in your stove.
If you have neither, you are likely mucking up your chimney big time now, considering the creosote deposits in your stove.
Ok have to do this from phone because computer browser isn't letting me attach for some reason.
So I took a vid this weekend. The top side areas are clear in this video but normally not and the middle is darker than normal I feel. Overall this isn't a bad view at all which is why I grabbed the video and this would be on the plus side of my experience with glass soot.
Also attaching picture of door soot before firing up the stove last weekend. Does this door stuff burn off when the next fire gets going?
Yes I imagine burning only on the weekends and letting this go out every week will add to my creosote.
![[Hearth.com] vermont castings intrepid flexburn trouble controlling burn](https://www.hearth.com/talk/data/attachments/301/301038-bd8ea3d227101c938d0ff207557ad88e.jpg?hash=SegQr4q1oC "[Hearth.com] vermont castings intrepid flexburn trouble controlling burn")
![[Hearth.com] vermont castings intrepid flexburn trouble controlling burn](https://www.hearth.com/talk/data/attachments/301/301039-fc01584380e3f3c3e3785fb29aa6f605.jpg?hash=u0HLyKmXTd "[Hearth.com] vermont castings intrepid flexburn trouble controlling burn")
This (sticky and running (liquid) creosote) is what I see when I go "full black box mode" on my (cat) stove (with the cat cleaning it up before it goes in the chimney).
If the stove burned like that video (flames) all the time, I think you have air leaks at the door or windows. Because that is not a "turned down smoldering"-fire which would (also) result in running creosote.
Air leaks let in cold air, cooling down combustion, and hence making that combustion incomplete --> creosote.
To the OP: if you have much draft, and are not smoldering, but end up with black windows (and have not turned down the stove), I think the same is present. You can have both (good/too much) draft that makes the stove less controllable AND black windows - if air leaks are present.
Hence, the dollar bill test (test all around the door), the solidity of the window in its frame, and the key damper in the flue that begreen suggested would be the first things I would do.
If the stove burned like that video (flames) all the time, I think you have air leaks at the door or windows. Because that is not a "turned down smoldering"-fire which would (also) result in running creosote.
Air leaks let in cold air, cooling down combustion, and hence making that combustion incomplete --> creosote.
To the OP: if you have much draft, and are not smoldering, but end up with black windows (and have not turned down the stove), I think the same is present. You can have both (good/too much) draft that makes the stove less controllable AND black windows - if air leaks are present.
Hence, the dollar bill test (test all around the door), the solidity of the window in its frame, and the key damper in the flue that begreen suggested would be the first things I would do.
that video I took was with the control all the way open. It dances gently when I turn it down, and is very hard to see when turned down all the way. I have no flames with a full wood box, that video it's probably only 1/3 full.
UPDATE: so I have been leaving more ash in the fire box than I would normally do and all the problems I spoke of earlier have subsided or stopped. No whistle and I have control over the flame with the air handler albeit either completely open (when starting) or completely closed (when it gets above 550 or so). I used to have more nuanced control with the air handler but at least it is not running wild anymore. The ash must be plugging holes somewhere. I put a call in to the dealer but no response. I though about calling VC directly. I still might.
UPDATE: I continued to have problems with the burn so I replaced the ash pan gasket and the damper gasket. I believe the damper gasket was the culprit, it was peeling away and brittle. whistle is gone and the air handler acts as it should again and can control the burn. when I tamped the air handler all the way down I had lots of back puffing. I then had to vacuum the 2 small holes in the burn plate that I had previously stuffed with ash to allow better air flow. That did it, window is no longer dark, control of the fire regained. thanks for all the helpful suggestions.
I know that you already replaced the gasket, but the damper is adjustable for when the gasket gets flattened out. I had to make an adjustment on mine about 1/2 way through my first year.
I did that last year. I need to do it after the gasket replacement. Today it ran wild again, whistling all the way to hot hot hot. Im close to calling in a technitian to take a look. air is seeping in to the burn chamber, likely through the damper opening as the new gasket fixed it temporarily but seems to still be a gap somewhere. Wonder if I need a new damper. the stove is only 2.5 seasons used. Waiting for it to cool to take a look.
I'm late to the party here but I have a Intrepid flexburn with about 2 years experience running it. I have the same issues with the glass getting dirty quickly. jstol I see your post where you vacuumed two small holes in the burn plate that took care of this issue. What burn plate are you referring too? When I bought the Intrepid was told by dealer right off not to expect the glass to stay clean. Maybe this is my problem as well??? The Damper gasket is a bear to replace correctly. The track needs to be perfectly clean and the damper closed on it to hold it in place till the gasket cement can dry. Otherwise the damper would need to be removed to facilitate cleaning and gasket replacement. Fun stuff. I attribute the dirty glass issue to the design of the airflow within the stove.
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