New stove creosote buildup

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grayhame

New Member
Jan 1, 2021
6
Tennessee
This year we decided to "upgrade" our stove. We've had a boxwood cast iron stove for the last 10 years and bought a firebox stove with a window. It gave us increased capacity and we thought higher heat output due to the BTU rating. We're kind of regretting it, since the cast iron stove radiated heat MUCH better than this new one. I bought a stove pipe heat reclaimer to try and make up for the radiating heat issue on the new one. When I disassembled the stove pipe, I found significant creosote buildup in the pipe. In 10 years of using our cast iron stove, that pipe has only ever had a soot layer build up on it. I cleaned up more creosote after 2 weeks of use on this new stove than I did on 10 years of the old one.

In researching, I think I've been using the new stove wrong. We're still figuring out the air control for this one. It has two levers for air control. One opens an air hole under the stove and at the back, I think this is my damper. The other opens an air hold underneath and at the front, they call this one the burn control. From what I've read, I should not be completely closing the damper lever and I think that's what's led to my buildup. I know my stove pipe doesn't get as hot as it used to with this one.

Can someone with some wisdom help me out? People use these stoves all the time to heat their homes, so I know I'm doing something wrong with it.
 
The old box stove was strictly a radiant heat stove. It had no heat shielding and required 36" clearances in all directions. Because of the simple internals, this style stove will draft on a 4ft flue. The VG is much more of a convective design, using the blower to warm up the room. It has much closer clearances due to the shielding and it is going to be more particular about having decent draft and fully seasoned firewood. Also, running this stove is going to be different, so there will be a learning curve for a week or two.

Don't give up hope, there may be some solutions. Can you post a picture of the stove setup and describe in detail the flue path from stove top to chimney top?
 
I have seen posts here that stove pipe heat reclaimers are creosote producing machines.
For sure this is a bad remedy for the situation. It should be removed. It's making a poor situation worse.
 
The old box stove was strictly a radiant heat stove. It had no heat shielding and required 36" clearances in all directions. Because of the simple internals, this style stove will draft on a 4ft flue. The VG is much more of a convective design, using the blower to warm up the room. It has much closer clearances due to the shielding and it is going to be more particular about having decent draft and fully seasoned firewood. Also, running this stove is going to be different, so there will be a learning curve for a week or two.

Don't give up hope, there may be some solutions. Can you post a picture of the stove setup and describe in detail the flue path from stove top to chimney top?
 

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Since it's the same chimney that served well for us with the old stove, how would it affect the new stove in a bad way?
Not nearly enough chimney height to power a modern stove.
 
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Different stove, but my Quadrafire 3100 ACT has two air controls like yours. Mine says to open both (for me that means PUSH the control handles in all the way) and let the fire get started. After 10 or 15ish minutes I close the air for the back of the stove and use the other one (air to the front of the stove) to govern how much air goes to the fire. Or I can leave both wide open and feed the stove more frequently. Hope this helps.
 
Using a heat reclaimer, causes the chimney to cool down too fast. Then the creosote will form.
Yes it does “cool” the chimney some, but burning seasoned wood keeps things “clean” too! I know plenty of people using them that don’t have problems with creosote. If the person is burning low and with wet wood, you will have the problem, which is why I said the user is causing the problem. Could be a drafting problem also!
 
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I don't know what my moisture content is.

1.) Where do you get your wood from?
Buy from someone or chop yourself?

2.) When it burns in the stove, do you hear a sizzling noise?
3.) Does it produce a lot of gray / black smoke?
4.) is the wood easy to light? Is it softwood like pine, or hardwood like oak and maple?

Did you change the source of wood from when you had the old cast iron stove? Sorry for so many questions, just trying to narrow down the culprit of your issue :D
 
Vogelzang VG3200-P

I have an older version of this stove. The handle on the right controls the air going in the front bottom. The handle on the left controls the secondary air which comes out of the small tubes in the top of the firebox. As others have said, you need dry wood. With dry wood I get very little creosote as long as I don't close the damper in the stove pipe too much. You should be able to see flames coming off of the secondary air tubes which is giving you great combustion and will heat up the top of the stove very well. Once you get the secondary air flames then start closing the bottom air a little at a time. As the stove warms you can keep slowing down air intake, but try to keep the secondary flames going. I can get 4 hours of high heat out of this stove or back it down to medium heat for 6.
Again dry wood is critical. I tried some oak that was only a year old and I had to run it wide open to burn the stuff so I could get dry wood in.
Hope this helps.
 
Since it's the same chimney that served well for us with the old stove, how would it affect the new stove in a bad way?
Thanks for the drawing. It illustrates the problem. The stove was tested with 15' of flue. This system only has 10ft of vertical rise, but a lot of that rise is negated by the long horizontal run which is really slowing down draft and the two 90º turns. Most modern stoves need a much stronger draft in order to pull the air through the manifolds and direct it over the glass and into the secondary tubes. The old box stove had nothing between the fire and the flue so it would work on a 6ft flue. There are some stoves that breathe easier due to shorter air paths. Drolet and Pacific Energy stoves are a couple of examples of stoves that work on a shorter 12 ft flue system. Note that that is straight up. Each 90º turn adds friction and reduces the effective height of the flue system by about 2ft. Horizontal runs should be kept as short as possible.

To improve the flue system, the horiz. run should be shortened and the interior 90 should be replaced with a pair of 45s and an offset. The exterior chimney will need 3-4ft additional length. The benefit of doing this will be easier starts, a much hotter fire, cleaner stove glass, and reduced wood consumption.

two 45s for flue connect.jpg