Strange Smoke in Bottom if Stove?

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Caw

Minister of Fire
May 26, 2020
2,555
Massachusetts


Osburn 1600 insert. Full load, cold start, top down method with kindling, 16-18% maple with one small mediocre ash piece probably 20-22%. Outside temp 38, inside 66. Rainy and slightly windy out.

Strange ignition. I hadn't lit it since yesterday AM as we had a 60 degree Xmas. The initial warm up and expansion tinks and tanks were there but it was extra today. They were louder, even sounded like a little vibration sometimes. The tubes were also SUCKING in air more loudly than usual...sounded like a hurricane. Overall just very weird.

I checked the door seal with a match and it's good. Cracked the door to outside for a minute, no change. No smoke coming inside the room just the strange noises and the visible smoke at the bottom of the stove that you can see in the video. Its been going about 40 mins now and it's settled in/no more weird noises or smoke.

Any thoughts on what that was? Ive just never seen that before so I'm curious. It always lights easily/smoothly.

Maybe just a weird piece of wood that wasn't as dry as expected and caused extra smoke and/or it collapsed on itself strangely? One mediocre split in the middle of a load of like 8 splits shouldn't matter that much but maybe on a cold start. Maybe the draft was a little weak with the higher outdoor temp. Idk.

Happy holidays!
 
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My pure guess was Thursday and Friday were both very heavy wind days from an unusual direction. Stack height and orientation can really impact things. That can introduce some real unusual draft conditions and modern stoves are very dependent on steady draft to do their magic. If you have a barometric damper on your oil or gas boiler you may have heard it flapping which is a good sign that the draft is varying up and down. Folks who know your specific type of stove may have further insight but I have seen really odd performance of many stoves when the wind is really cranking.

For those with first generation Vermont casting stoves like my old Defiant, high winds made backpuffing far more prevalent.
 
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Gordon brought in some wet wood
 
My pure guess was Thursday and Friday were both very heavy wind days from an unusual direction. Stack height and orientation can really impact things. That can introduce some real unusual draft conditions and modern stoves are very dependent on steady draft to do their magic. If you have a barometric damper on your oil or gas boiler you may have heard it flapping which is a good sign that the draft is varying up and down. Folks who know your specific type of stove may have further insight but I have seen really odd performance of many stoves when the wind is really cranking.

For those with first generation Vermont casting stoves like my old Defiant, high winds made backpuffing far more prevalent.
The Eastern US has been getting record winds for the past few days/nights, so I would assume it is wind related as well.

We experienced the Defiant I high winds backpuffing and that was the last time we used it.
 
I am pretty sure that was the issue. Also I noticed later in the burn I got another good pocket of off gassing so likely something was smoldering a little on the bottom due to weird draft and how it was packed....and Gordon doing a bad wood run.. lol. Running fine now.
 
The way this smoke flows to me simply suggests a (apparently for you uncommon) air flow pattern; locally the smoke does not easily flow to the exit of the stove. One parameter that will affect this is the geometry of logs in the firebox, apparently creating a pocket where gases don't easily escape. Like fog in a valley..

That might be influenced also by the total gas flow speed in the system, and thus the weather.

But local (in-firebox) parameters will have to be just right to allow this to happen.

Nothing to worry about, I think.