Smoke when closing the door after starting the stove

[yuryk]

Dear community!

So far I did 2 fires in my new Lopi Large Flush Wood fireplace insert. First one had much drier wood (leftovers from previous owners, so pretty sure it's dry), while second one having much more wet wood (there was a lot of soot on the stove itself and the glass). Although, in both cases when I close the door after fire got bigger, I see a lot of smoke rolling inside of the stove. The flue damper was wide open, the air intake was also open. This is how it looked:

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Do you know what might be the reason for that? I have used newspaper with dry bark instead of kindling for ignition. Can it be because of bark? Or maybe it's just normal when the stove is cold?

Thank you in advance!

 

[stoveliker]

Try to start a top down fire.

And the drier the wood the less smoke.

I think you could have kept the door on a crack a bit longer too.

 

[vatmark]

Have you tried preheating the chimney before lighting the fire? I have a freestanding wood stove and use a propane torch to preheat the chimney. You can also use a hairdryer.

 

[EatenByLimestone]

How tall is the chimney and is there a liner?

 

[bholler]

Also what was the outside temperature?

 

[yuryk]

Try to start a top down fire.

Definitely will try next time!

And the drier the wood the less smoke.

Yeah, that I figured. First burn I did not see any smoke from the chimney, while second burn there was some even on this low burn:

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By the way, you can see the secondary combustion is not working - I assume this is due to a lower temperature, which is due to less drier wood, right? It worked right after I shut down the air intake, but then quickly died down.

I think you could have kept the door on a crack a bit longer too.

How long should it be? Or what would be the sign it's okay to close it? In @begreen 's post Starting a fire and running an EPA stove I did not find time for the door specifically...

Have you tried preheating the chimney before lighting the fire?

I tried, yes - I got a newspaper and burned it at the top of the stove, near the flue connector. But I'm not sure for how long should I do that - I guess it's another question... I don't have any fixed thermometers unfortunately, just an IR one.

How tall is the chimney and is there a liner?

It's about 30 feet. Yes, there is an insulated liner, installation details can be found here.

Also what was the outside temperature?

About 55-60F.

I would like to add that when I open the door, the draft is perfect - all that smoke goes up the chimney. But when I close it - it rolls on the glass just like that...

As I mentioned, I don't have any fixed thermometers, I only use IR. What is the best/simplest way to install a fixed one? I assume the best one would be a flue one and that would require installing a probe? Is it a pain to install? Is it absolutely necessary?

 

[stoveliker]

How long should it be? Or what would be the sign it's okay to close it? In @begreen 's post Starting a fire and running an EPA stove I did not find time for the door specifically...

It depends on a lot of factors,.such a load, dryness, flue height, outside temperature etc. No time can be given.
I'd say when it burns well,.close to a crack, when it burns vigorously close.it completely.
Do look at how the fire looks in the thread you mention. That look is more a guide than the time.

I would like to add that when I open the door, the draft is perfect - all that smoke goes up the chimney. But when I close it - it rolls on the glass just like that...

The point is not the smoke roll like that(it doesn't come into your room so it IS going up the chimney), but the fact that you have so much smoke. If all.is going as it should, you shouldn't see that.

I think tho,.that the outside temp was.so high that it decreased draft, leading to some flame extinction and hence smoke when you closed the door (leading to less air). That in combi with subpar wood gets a smoky mess.

 

[bigealta]

Wet wood/ Not seasoned enough, Is 95% of the smoke problem i'd bet.

Next time try top down as mentioned. Cuts smoke way down.

And the video with the blue flames looks fine to me. Blue flames are good. That stage is past secondary burn stage it looks like. It's starting the coaling stage.

 

[stoveliker]

And the video with the blue flames looks fine to me. Blue flames are good. That stage is past secondary burn stage it looks like. It's starting the coaling stage.

Yeah, it wasn't clear to me from the post whether at the time of the video there still was smoke coming from the chimney (in my stove such blue flames would never give any smoke, whether they are at the bottom of the firebox or at the top).

 

[bigealta]

Here is a top down, you may want to use more kindling and smaller splits in the middle row than i did in this one.

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[begreen]

About 55-60F.

I would like to add that when I open the door, the draft is perfect - all that smoke goes up the chimney. But when I close it - it rolls on the glass just like that...

Draft will increase notably as the outside temperature drops to 45º.

 

[yuryk]

I'd say when it burns well,.close to a crack, when it burns vigorously close.it completely.
Do look at how the fire looks in the thread you mention. That look is more a guide than the time.

Thank you, that helps. I wish I had thermometers like @begreen has. I think flue temp helps a lot, but it would be a pain for me to install it I guess...

If all.is going as it should, you shouldn't see that.

Even in the very beginning when starting the fire there should not be smoke, right?

Yeah, it wasn't clear to me from the post whether at the time of the video there still was smoke coming from the chimney (in my stove such blue flames would never give any smoke, whether they are at the bottom of the firebox or at the top).

Yes, I specifically checked that - there was a little bit of smoke coming out the chimney during that stage. That's when I noticed the secondary combustion tubes are not working, so I assumed - maybe that's the reason, coz otherwise that smoke would re-burn?

Blue flames are good. That stage is past secondary burn stage it looks like. It's starting the coaling stage.

Well, there were coals, but there was wood to burn as well. That blue fire is always there when I close the air intake almost completely. But when I open it again - the intense fire returns back. You can see it in this video (from the first burn):

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But the issue I have is that these secondary combustion tubes only have flames few minutes after I close the air intake. After that it's just those bottom blue fire. Do you guys have the same? Or, as my assumption is, it would depend on the burning temperature, which would be higher with properly seasoned wood, thus giving longer secondary burns. What do you think?

Here is a top down, you may want to use more kindling and smaller splits in the middle row than i did in this one.

Thank you! As I mentioned, I used bark - is it a good kindling in general? Or it creates more smoke/soot?

 

[begreen]

But the issue I have is that these secondary combustion tubes only have flames few minutes after I close the air intake. After that it's just those bottom blue fire. Do you guys have the same? Or, as my assumption is, it would depend on the burning temperature, which would be higher with properly seasoned wood, thus giving longer secondary burns. What do you think?

That looks like a clean hot fire. If no smoke out of the chimney it's working well.

Some thin bark is ok, but others create a lot of clinkers. A better kindling is splitter trash dried out well. Or ask some cabinetry, finishing,
or flooring shops for unfinished scrap cutoffs. Or if there is a lot of home construction in the area, get 2x4 and 2x6 cutoffs and split them into kindling with a hatchet.

 

[yuryk]

That looks like a clean hot fire. If no smoke out of the chimney it's working well.

Shouldn't the secondary tubes be burning all the time during that?

 

[stoveliker]

No, only when there is fuel to burn that didn't get combusted in the primary fire.

The problem I see is not with the flame but with the fact.you still saw smoke out of your chimney at that time.
However, with warm weather and hence less draft, I could see not enough air being sucked in thru the secondary pipes.

 

[Ctwoodtick]

I’m in the same climate as you, and I’d probably get some smoke roll out too if starting a fire any time recently.