Ash clogging flue?

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KG19

Member
May 15, 2022
83
SW Wisconsin
Kind of a stupid question here… so the other night I was unloading some ash into the ash pan below my wood stove, and I had quite a bit of buildup from not emptying much recently. Anyways, I ended up getting a fair amount of hot coal bits mixed in and when I got it in the ash pan, it became really hot. I ended up panicking and scooping all of the ash and coals back on top of the new fire I had just reloaded and let it burn for the night. Since then, I have been having major draft issues… could it be possible that the strong draft during the fire sucked a bunch of that ash up into the flue and is clogging it?? I’m pretty new to wood stoves so this mind be really stupid to ask. Otherwise maybe it’s a coincidence and something else is going on. But when I close the door, the flames basically just die out almost completely. This didn’t used to happen. Kind of at a loss on what to do, any advice is appreciated. Thanks in advance!
 
Kind of a stupid question here… so the other night I was unloading some ash into the ash pan below my wood stove, and I had quite a bit of buildup from not emptying much recently. Anyways, I ended up getting a fair amount of hot coal bits mixed in and when I got it in the ash pan, it became really hot. I ended up panicking and scooping all of the ash and coals back on top of the new fire I had just reloaded and let it burn for the night. Since then, I have been having major draft issues… could it be possible that the strong draft during the fire sucked a bunch of that ash up into the flue and is clogging it?? I’m pretty new to wood stoves so this mind be really stupid to ask. Otherwise maybe it’s a coincidence and something else is going on. But when I close the door, the flames basically just die out almost completely. This didn’t used to happen. Kind of at a loss on what to do, any advice is appreciated. Thanks in advance?
Is this a catalytic stove? If so, check the catalyst to see if ash is plugging it.

If it's a non-cat, is the wood from a different pile or species? Poorly seasoned wood will act this way.
 
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Our old top cap had a fairly fine mesh to keep critters and birds out--if I got a blast of ash going up the chimney it would sometimes clog the mesh enough that the draw would be reduced. Typically it was when I was burning wood that was not real dry.

It was a simple matter (at least for me with a flat roof) to go have a look, and knock the ash off as needed.
 
I use a spare cast iron dutch oven for hot coals, and an ash bucket for ashes. I have seen them relight in a minute or two after pulling them out. As far as the draft, Im kinda new too. Maybe the wood is wet?
 
It’s a non-catalyst stove. So I had a new development that makes me think something is definitely clogged. Tried lighting it today and smoke came out the seams of the stove pipe. I panicked and ended up using the fire extinguisher to put out the fire… huge mess. Probably the wrong thing to do but I panicked. I won’t be using it again until I have a professional come and take a look.
 
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Yeah sounds like something is very wrong. Smoke coming out isnt good I would think. The manual for my wood burner says if its glowing red, its too hot. LOL......no [email protected] hot.
 
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Once stove is cool and clean of the fire extinguisher material, can run a brush through the flue to see if that is the problem?
 
the only other thought I have (in my non-professional bag of tricks) is if the large amount of ash you dumped on the fire at once block up the “doghouse” air inlet. That said, I don’t know if that alone would cause the significant draft issue you suddenly have. That air supply usually enters stove inside the door, front center near the floor of the stove. Maybe worth clearing that area with a poker tool, as that would be the easiest of the solutions.
 
Yeah sounds like something is very wrong. Smoke coming out isnt good I would think. The manual for my wood burner says if its glowing red, its too hot. LOL......no [email protected] hot.
It definitely wasn’t glowing hot or anything, there was just a kindling fire in there. But it wasn’t drafting at all so the smoke was coming out of the seams of the stove pipe. Definitely something wrong though…
 
Good advice....warm the flue up. Ive had this happen to me too once or twice. I usually use a little sace heater with a blower. I sit it in front of the door, open the draft, go have a beer or coffee, by then the flue is warm. Try something like that before you call anyone....its worth a shot. Ive had a small smoky fire going for an hour before, then finlaly it drafted. Needless to say, it was smoky in here....I didnt warm the flue up that time. My mistake. Then I still use a rolled up paper to warm it up more....this is only whe its real cold out. Like under 15-20F. Go Pack!!! Sorry, I had to say it, its my team!!
 
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It was in the single digits here yesterday, so it was cold for sure. If it was just this one incident I would have assumed it was just a cold flue causing it. But the previous couple days when I had an actual hot fire going it seemed like the draft was really poor then too, even when my probe was reading 400 F. As soon as I shut and latch the door everything starts to die down, but the probe thermometer would still stay up at 300 or above. I don’t know, it’s just weird.
 
the only other thought I have (in my non-professional bag of tricks) is if the large amount of ash you dumped on the fire at once block up the “doghouse” air inlet. That said, I don’t know if that alone would cause the significant draft issue you suddenly have. That air supply usually enters stove inside the door, front center near the floor of the stove. Maybe worth clearing that area with a poker tool, as that would be the easiest of the solutions.
I did check out the primary air inlet for ash. I made sure it was clear before I tried starting it up yesterday
 
Once stove is cool and clean of the fire extinguisher material, can run a brush through the flue to see if that is the problem?
I was ready hoping that I didn’t damage the stove by shooting the fire extinguisher into it. I knew it probably wasn’t the right thing to do but I panicked. I don’t have a brush to clean it myself so I’m hoping that maybe the company I hired will come back and take a look since it’s less than 30 days since they cleaned it. Maybe that’s wishful thinking but worth a try
 
Based on the description, it sounds like the flue system is plugged. The most common cause is creosote clogging the cap screen. It doesn't sound like the issue is with the stove, but it may be the wood.

Has the interior moisture content of the wood been tested? What stove make/model is this?
 
Based on the description, it sounds like the flue system is plugged. The most common cause is creosote clogging the cap screen. It doesn't sound like the issue is with the stove, but it may be the wood.

Has the interior moisture content of the wood been tested? What stove make/model is this?
That’s what I was thinking… just confusing since I had the chimney professionally swept on Dec. 6, and haven’t been using it every day since then.

Is it possible that 15ish days of use could cause the chimney cap to become clogged with creosote?? I used it for about 4 months previous to the cleaning without issues.

That being said, my wood isn’t at the moisture level that’s recommended since it’s my first year building up my wood stash. I’m burning ash and a bit of soft maple that was split and stacked in April, most is in the low 20s moisture content.

The stove is a Woodpro 2000, which I believe is a cheap big box store wood stove, it was in the house when we moved in last November. We had in fully inspected last February and used in for about a month last year and then for a couple months this year prior to having it swept about 2 weeks ago.

Would you recommend contacting the company that swept it?
 
Is it possible that 15ish days of use could cause the chimney cap to become clogged with creosote?? I used it for about 4 months previous to the cleaning without issues.
Yes, it's possible, especially if the cap screen is fine. Soft maple can hold a lot of water and take time to dry out all the way inside. I experienced this many years ago with some poorly seasoned soft maple. The cap screen was plugged in 3 weeks.

Was any cardboard, or large volume of paper burned during this period? That can also clog a screen quickly.
 
Yes, it's possible, especially if the cap screen is fine. Soft maple can hold a lot of water and take time to dry out all the way inside. I experienced this many years ago with some poorly seasoned soft maple. The cap screen was plugged in 3 weeks.

Was any cardboard, or large volume of paper burned during this period? That can also clog a screen quickly.
I’ve never burned any cardboard, and only use a bit of newspaper when starting a fire. I’m just surprised that it can happen that quickly… I’d say 95% of what I’ve been burning is ash and maybe 6-10 total splits of silver maple
 
I went to the Woodpro web site to see what your stove was like. It shows in the maintenance video how to look up the chimney with a mirror. That is what I would do to start with. I would go up and look at the top of the chimney and sweep it, if you can't do that then I would call a sweep for an inspection and a sweep.
 
At this point, we can only point to the most common causes of poor draft. There are some others, but we're not on the scene looking at the system so we have to rely on your eyes. Is there a cap screen? How is the stove vented? Describe the flue system from stovetop to chimney cap. Do you know what brand of chimney system is installed?
 
At this point, we can only point to the most common causes of poor draft. There are some others, but we're not on the scene looking at the system so we have to rely on your eyes. Is there a cap screen? How is the stove vented? Describe the flue system from stovetop to chimney cap. Do you know what brand of chimney system is installed?
I really do appreciate all the help, sorry I’m not doing the best job describing everything. So here’s a picture of the inside and outside setup.

I’ll start by saying that the stove was here when when we moved last November, and I knew absolutely nothing about wood stoves (I now know only slightly more after spending a ton of my free time researching things, but still feel very not knowledgeable). So when we had it inspected, I didn’t even know what to ask about. Basically I know that it’s a double wall stove pipe running into a pre-existing masonry chimney… that’s about it. I can’t even visibly see a chimney cap from ground level but assume there has to be something up there. I also don’t have a way of getting up on the roof, especially at this time of year. When they sweep it, they just remove the stove pipe and clean that separately, then use their drill attachment to sweep the chimney from the bottom up.

I had been planning on buying a soot eater attachment to sweep it myself mid season, in addition to having it professionally swept each year. I’m wondering if just sweeping it from the bottom is enough to clean the actual cap?

[Hearth.com] Ash clogging flue? [Hearth.com] Ash clogging flue?
 
it wouldn’t surprise me if there is no chimney cap. A lot of brick and masonry chimneys around here don’t have a cap.
 
it wouldn’t surprise me if there is no chimney cap. A lot of brick and masonry chimneys around here don’t have a cap.
The picture helps a lot. The flue tile may be uncapped with a stone cap 4-6" above it. That's typical. Some of these setups are screened, but a lot are not.
 
I really do appreciate all the help, sorry I’m not doing the best job describing everything. So here’s a picture of the inside and outside setup.

I’ll start by saying that the stove was here when when we moved last November, and I knew absolutely nothing about wood stoves (I now know only slightly more after spending a ton of my free time researching things, but still feel very not knowledgeable). So when we had it inspected, I didn’t even know what to ask about. Basically I know that it’s a double wall stove pipe running into a pre-existing masonry chimney… that’s about it. I can’t even visibly see a chimney cap from ground level but assume there has to be something up there. I also don’t have a way of getting up on the roof, especially at this time of year. When they sweep it, they just remove the stove pipe and clean that separately, then use their drill attachment to sweep the chimney from the bottom up.

I had been planning on buying a soot eater attachment to sweep it myself mid season, in addition to having it professionally swept each year. I’m wondering if just sweeping it from the bottom is enough to clean the actual cap?

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The pictures are very helpful. I can see why you can't easily determine what is happening at the chimney top.

Do you know if there is a 6" stainless liner in the chimney that the stovepipe connects to or is the chimney just clay tile lined?
 
The pictures are very helpful. I can see why you can't easily determine what is happening at the chimney top.

Do you know if there is a 6" stainless liner in the chimney that the stovepipe connects to or is the chimney just clay tile lined?
I honestly wish I had a drone or something I could fly up there just to get a visual of it haha. Even if I could get up on the roof when there isn’t snow or ice (probably 4 months from now) the chimney is still tall enough I don’t know if I could see the top…

I’m not sure about the liner situation either, but I should be able to remove the stove pipe and take a look I’d think. Especially if I do plan to try to sweep it out with the soot eater. Haven’t fully made up my mind on if I want to try that myself quite yet though.