Woodstock Fireview.....coaling problem

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sailor61

Burning Hunk
Nov 28, 2006
124
Warwick, RI
I've been burning the FV for only a few weeks. Until this weekend I was getting good clean burns with just fairly clean white ash left. The last two days I've been running into excessive coaling which is cutting back on my heat output and my ash bed has more chunks left in it. Have good draft and am using the same marginal wood supply I've had all along.

Process is I load the stove (move coals towards the back and then 3 or 4 splits into the box), leave vent open, cat bypassed for at least 15 or 20 minutes. Then I engage the cat and bring the air down to 1. After I see a rise in the STT I move the air down to around .75 or so. I am getting a good secondary burn which peters out at some point -which I read to be normal. Smoke output is the same as it has been - heavy when in bypass but steam (or nothing) when in cat.

Wood is mainly oak (not sure if red or white) with an occasional piece of cherry mixed in. Last night I made sure to use just oak in case the cherry was leading to this. I know my wood isn't seasoned as well as it should be but, by the time this heavy coaling is occuring, any moisture (I would think) has been long driven off.

Today I've decided to let the stove burn down as low as I can get it and then clean out most of the remaining ash to see if that helps to reduce this. Thoughts? Anything else I can try ? Is this just something I need to accept?
 
You were burning during some exceptionally cold weather two to four weeks ago, when you had it burning more completely, and things were a little warmer last week... are you sure the problem was this weekend, and not all of last week? The cold weather would have given you notably better draft.

Also, oak takes much longer to season (2 - 3 years) than cherry (1 year). If these woods were cut and split around the same time, the oak is likely to cause you more trouble than the cherry.
 
I've been burning the FV for only a few weeks. Until this weekend I was getting good clean burns with just fairly clean white ash left. The last two days I've been running into excessive coaling which is cutting back on my heat output and my ash bed has more chunks left in it. Have good draft and am using the same marginal wood supply I've had all along.

Process is I load the stove (move coals towards the back and then 3 or 4 splits into the box), leave vent open, cat bypassed for at least 15 or 20 minutes. Then I engage the cat and bring the air down to 1. After I see a rise in the STT I move the air down to around .75 or so. I am getting a good secondary burn which peters out at some point -which I read to be normal. Smoke output is the same as it has been - heavy when in bypass but steam (or nothing) when in cat.

Wood is mainly oak (not sure if red or white) with an occasional piece of cherry mixed in. Last night I made sure to use just oak in case the cherry was leading to this. I know my wood isn't seasoned as well as it should be but, by the time this heavy coaling is occuring, any moisture (I would think) has been long driven off.

Today I've decided to let the stove burn down as low as I can get it and then clean out most of the remaining ash to see if that helps to reduce this. Thoughts? Anything else I can try ? Is this just something I need to accept?
I get coaling once in while myself. Generally, I burn it down as far as I can, and load with smaller wood to get a super hot fire. I leave it all the way open for 1/2 hr to an hr. Then the remain coals burn down to ash and sift through the grate to the ash pan. Using a variety of hardwoods in no particular order. All dried at least two years with the exception of surface moisture now and then depending I brought in wood out of the rain. All in all, the oslo is cooking fine.
 
The problem became noticeable yesterday morning...so the Saturday fill seems to be when it started.
 
I'm getting some similar results this week. I know my isssue is wood related. I had a large pile fall and know down some less than dry ash. I just moved it all sorting as best i could. I think this will resolve to a large extent when you burn 2 year old Old and one year old everything else. Great wood great results ; )
 
1) If you are home, and have to time-you can open the draft at the end of the burn and burn the coals down, while maintaining STT.
2) More air, same load size, same burn time.
3) Same air, smaller load size, same burn time.
4) Keep the ash cleaned out, the coals bury up and don't burn down.
 
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I've been thinking back to Saturday night .....had company in and it was HOT in the den where the stove. Opened windows a bit to cool it down. Coompany left around 12, picked up for 1/2 hour or so. When I went to bed I decided to try and bank the remaining coals and pushed them forward....the problem started that night. Wondering if I might have done something to partially plug the air supply which I believe is under the front window on a FV. I'm going to let it burn way down then clean it out and take the ash vac to it the air inlet.
 
The air enters above the glass and "airwashes" down.
 
1) If you are home, and have to time-you can open the draft at the end of the burn and burn the coals down, while maintaining STT.

I've wondered about this myself... how far to open the air to burn down those coals? My theory being that opening it too far is likely counterproductive, washing more heat up the chimney than perhaps opening the control just half way.
 
sad to admit I don;t know where the air supply is in my own stove....
 
I've wondered about this myself... how far to open the air to burn down those coals? My theory being that opening it too far is likely counterproductive, washing more heat up the chimney than perhaps opening the control just half way.
I think that's correct, so I usually open the air on the Fv to a little over '1' to burn 'em down.
Wood is mainly oak (not sure if red or white) with an occasional piece of cherry mixed in. Last night I made sure to use just oak in case the cherry was leading to this. I know my wood isn't seasoned as well as it should be but, by the time this heavy coaling is occuring, any moisture (I would think) has been long driven off.
Today I've decided to let the stove burn down as low as I can get it and then clean out most of the remaining ash to see if that helps to reduce this. Thoughts? Anything else I can try ? Is this just something I need to accept?
I've seen folks say here that wood that's not quite dry will cause more coaling but like you, I don't see how there can be any moisture in the wood late in the burn. All the moisture should be gone at the coaling stage, and the coals should burn down I would think. But I've been wrong a couple times before. ;lol I believe that Oak is known to have a long coaling stage...
I've been burning down the coals during the day. I'll pull them to the front and open the air to a little over '1'. Later I'll jam a poker under the coals and lift it up through them to expose the bigger chunks and knock the ashes off them. Once I get the coal bed small enough, I can shift the big stuff to the front and scoop out the back. I get a shovel-full (trying to leave an insulating layer on the floor of the box.) The bigger coals seem to end up on top, and can be shaken off the shovel. Then I'll skim the bigger ones from the front to the space I've just cleared out in the back, and shovel out the front. Then push 'em forward and reload.
You'll notice on a full load that when you cut the air, the wood in the front uses the oxygen that's coming in the airwash (at the top of the window.) The wood in the front burns but there are no flames in the back. I put a partial load of Cherry in a while ago and it occurred to me that I could load the partial in the back of the stove, leaving the coals in the front. Maybe then they would burn down more with better access to the incoming air, but I would still be getting good cat heat off the wood burning in the back. I'll have to play with this idea.
A lot less bullcrappin' around with an ash grate and pan; Automatically drops the little stuff out the bottom whilst leaving the big coals in the box. Not to mention that the little ones burn out in the ash pan and you get that heat as well. I never dump an ash pan right after I've put stuff into it. I wish Woodstock had a stove with a box the size of the Fv, but the ash drawer system and the big window of the Keystone. Don't really want to spend more money on another stove but if this were to become available, I would be totally down with it. ::-) While they're at it, they could put in the heat-scavenging fins of the PH. Hmmm, not sure that would be as productive on a cat non-hybrid...
 
I've been burning the FV for only a few weeks. Until this weekend I was getting good clean burns with just fairly clean white ash left. The last two days I've been running into excessive coaling which is cutting back on my heat output and my ash bed has more chunks left in it. Have good draft and am using the same marginal wood supply I've had all along.

Process is I load the stove (move coals towards the back and then 3 or 4 splits into the box), leave vent open, cat bypassed for at least 15 or 20 minutes. Then I engage the cat and bring the air down to 1. After I see a rise in the STT I move the air down to around .75 or so. I am getting a good secondary burn which peters out at some point -which I read to be normal. Smoke output is the same as it has been - heavy when in bypass but steam (or nothing) when in cat.

Wood is mainly oak (not sure if red or white) with an occasional piece of cherry mixed in. Last night I made sure to use just oak in case the cherry was leading to this. I know my wood isn't seasoned as well as it should be but, by the time this heavy coaling is occuring, any moisture (I would think) has been long driven off.

Today I've decided to let the stove burn down as low as I can get it and then clean out most of the remaining ash to see if that helps to reduce this. Thoughts? Anything else I can try ? Is this just something I need to accept?
I had the same problem last week when I burned some hedge a couple nights in a row,the wood is 2 years old minimally probably need to check it on a fresh split.A heavy coal bed definitely affects heat output.
 
I've been burning the FV for only a few weeks. Until this weekend I was getting good clean burns with just fairly clean white ash left. The last two days I've been running into excessive coaling which is cutting back on my heat output and my ash bed has more chunks left in it. Have good draft and am using the same marginal wood supply I've had all along.

Process is I load the stove (move coals towards the back and then 3 or 4 splits into the box), leave vent open, cat bypassed for at least 15 or 20 minutes. Then I engage the cat and bring the air down to 1. After I see a rise in the STT I move the air down to around .75 or so. I am getting a good secondary burn which peters out at some point -which I read to be normal. Smoke output is the same as it has been - heavy when in bypass but steam (or nothing) when in cat.

Wood is mainly oak (not sure if red or white) with an occasional piece of cherry mixed in. Last night I made sure to use just oak in case the cherry was leading to this. I know my wood isn't seasoned as well as it should be but, by the time this heavy coaling is occuring, any moisture (I would think) has been long driven off.

Today I've decided to let the stove burn down as low as I can get it and then clean out most of the remaining ash to see if that helps to reduce this. Thoughts? Anything else I can try ? Is this just something I need to accept?


Sailor, your experience with the coaling is not unusual, especially when it is cold and we are pushing the stove. However, I see a couple things that perhaps might help you.

First is as others stated and yourself admitted the oak is not seasoned as well as it could be. That alone will cause excessive coaling.

Second, is your practice of pushing the coals towards the back of the stove. Whoops! Do it the opposite way. Never move them to the back of the stove.

Even though we have very dry wood, when we first started burning with the Fireview we too had a problem with too many coals. It happened once the weather turned cold and if the house started getting cool we'd put more wood in the stove. It did not take long before we had about a half full firebox with nothing but hot coals. I could never find a decent answer for stopping this problem including putting some kindling on the coals and open the draft full. So, I began experimenting. Here is what we found.

Looking at the fire, just before the firebox was down to all coals (still at least) one shape of a partial log, I would simply open the draft full. Stovetop temperature would usually be around 400 degrees and lower during the real cold our house would get cold. I don't like that. But we found by opening the draft full that the stove would maintain the temperature while burning down the coals. I have even at times opened the firebox door and shoved the big pile of coals (they are always toward the rear of the firebox) toward the front and middle. This has stopped all problems we had with excessive coals.


Actually during the daytime hours we will simply level the coals out before adding wood but when we need a long burn, the coals get pushed to the front. I like to have a small pocket in the bottom rear of the stove where we tend to place a rectangular split tight against the back of the stove with few if any coals under that piece. Then if I have some soft maple or elm I'll put one piece in the front bottom; right on those hot coals and then fill the rest of the stove with whatever we have planned.

I hope this helps, especially if you try opening the draft wide open. Some have said they like to open the firebox door a little and it might work but that also will introduce more cool air to the stove and your stove top temperature may not maintain the heat it needs to keep you warm.
 
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Im having the same problem this week and last. I tried an experiment on Saturday the stt was down to just under 300 so I opened the air and the bypass put in one small split about 18" long and 2" around. After it was charred I closed the bypass and shut the air to 2.5 and left it. After about 30 minutes the stt was at 350 and we left the house for a couple hours when we got back the stt was 450 and all the big coals were gone. Now I've only done it once my wife tried to do it again today but forgot the bypass and left the air open full. Ill try it again this week hopefully with the same results.
 
I think when the ash builds up it packs between the coal chunks and keeps air from getting to them so that the coals can burn down.

You can keep mixing them up to expose them to air and keep the door cracked or by putting a small piece of wood to burn on top the burning wood will suck more air thru the coals. But if the ash is packed too tight I dont know how much good it will do as I at times havent had good luck with burning a small split on the coals at high rates.
 
After reading the owners manual on the FV,, I almost feel like they don't want you running the stove in the cat mode with the draft open more then 1.. Just be interested to hear what others have ran their stoves at with no damage to the stove or the cat... My fear would be sucking ash into the cat or flames? Even though the air scoop has a screen on it.. At times I would love to run my stove at 1.5 if I've gotten behind on heating the place, especially in the single digits..I usually run my stove at .75 to just under one..
 
After reading the owners manual on the FV,, I almost feel like they don't want you running the stove in the cat mode with the draft open more then 1.. Just be interested to hear what others have ran their stoves at with no damage to the stove or the cat... My fear would be sucking ash into the cat or flames? Even though the air scoop has a screen on it.. At times I would love to run my stove at 1.5 if I've gotten behind on heating the place, especially in the single digits..I usually run my stove at .75 to just under one..

Woodstock told me not to run the cat with the air open more than 1.5-2.
 
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1) If you are home, and have to time-you can open the draft at the end of the burn and burn the coals down, while maintaining STT.
2) More air, same load size, same burn time.
3) Same air, smaller load size, same burn time.
4) Keep the ash cleaned out, the coals bury up and don't burn down.


I have had similar experiences with my Fireview. If the coals are buried they can't burn
 
they encourage lower settings on the cat for several reasons...ash, flam damage and because too much air leads to turbulence that will keep it from burning properly.
 
they encourage lower settings on the cat for several reasons...ash, flam damage and because too much air leads to turbulence that will keep it from burning properly.
1 is usually the highest setting I run with the cat engaged.. I like to run the stove @ .5 at times which works great, but then I too wind up with a big load of coals at the end of the burn... I'm burning silver maple...
 
4) Keep the ash cleaned out, the coals bury up and don't burn down.

Perhaps good advice, but I wouldn't go too far with that cleaning. Some stove manuals, specify you should establish and maintain a good ash bed in the stove. For example, my Jotul manual clearly states, "Do not remove all of the ashes from the stove. The stove will perform better if you maintain about a 1" layer of ashes in the bottom of the stove."
 
Sailor, your experience with the coaling is not unusual, especially when it is cold and we are pushing the stove. However, I see a couple things that perhaps might help you.

First is as others stated and yourself admitted the oak is not seasoned as well as it could be. That alone will cause excessive coaling.

Second, is your practice of pushing the coals towards the back of the stove. Whoops! Do it the opposite way. Never move them to the back of the stove.

Even though we have very dry wood, when we first started burning with the Fireview we too had a problem with too many coals. It happened once the weather turned cold and if the house started getting cool we'd put more wood in the stove. It did not take long before we had about a half full firebox with nothing but hot coals. I could never find a decent answer for stopping this problem including putting some kindling on the coals and open the draft full. So, I began experimenting. Here is what we found.

Looking at the fire, just before the firebox was down to all coals (still at least) one shape of a partial log, I would simply open the draft full. Stovetop temperature would usually be around 400 degrees and lower during the real cold our house would get cold. I don't like that. But we found by opening the draft full that the stove would maintain the temperature while burning down the coals. I have even at times opened the firebox door and shoved the big pile of coals (they are always toward the rear of the firebox) toward the front and middle. This has stopped all problems we had with excessive coals.


Actually during the daytime hours we will simply level the coals out before adding wood but when we need a long burn, the coals get pushed to the front. I like to have a small pocket in the bottom rear of the stove where we tend to place a rectangular split tight against the back of the stove with few if any coals under that piece. Then if I have some soft maple or elm I'll put one piece in the front bottom; right on those hot coals and then fill the rest of the stove with whatever we have planned.

I hope this helps, especially if you try opening the draft wide open. Some have said they like to open the firebox door a little and it might work but that also will introduce more cool air to the stove and your stove top temperature may not maintain the heat it needs to keep you warm.

I have been doing this method since Dennis posted it a few years ago. Works great. I have also from time to time, when I don't have the time to burn down coals, shoveled them out into my steel pail and dumped them in the covered steel trash can that I keep outside.
 
What Woodstock is concerned with would be that folks would start running the stove at full draft when the cat is engaged and wood is burning. Once the fire is down to all coals, there is not much there that would harm the catalyst or flue. So for sure if someone reads this thread, don't run the draft open very far when you are burning wood and the cat is engaged! Once you have just coals, there is not much to harm.
 
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Yes what Dennis said I should have been more specific I only do this with little to no flame.
 
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