Sudden Smoke Problem

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ackvor

Member
Jan 20, 2019
8
New England
Hi everyone and thanks in advance for checking out my question. I’ve had a Jotul F3CB for about 4 years now. The first three seasons, I have not had any problems. This year I am having a wicked smoke issue when I open the door. Here are the things I’ve checked/tried:

-professional inspection/cleaning. He said all was fine and it was the wood we were using. (1.5year old self harvested oak)

-switched to kiln dried birch/ash/hickory wood. Very nice, but same problem

-no new fans/vents etc installed.

-build fire in back on stove, close off air before opening

-tried opening doors/windows. No help.

Any ideas? I’m stumped. Thanks.
 
Is the stove pipe coming out the top or back? Describe your chimney for us, do you have a chimney cap with a screen?
 
Is the stove pipe coming out the top or back? Describe your chimney for us, do you have a chimney cap with a screen?
Thanks. The pipe comes out the back of the stove. The stove is set into a fireplace. The cap is a pretty standard (I think) non screened, single flue cap. The chimney has a stainless liner installed.
 
Take the pipe off the back and look in it, you might have ash build up or debris on the 90deg section, also check your clean out for the same thing, either climb up or check with binoculars the cap for a plug up, def sounds draft related.
 
Take the pipe off the back and look in it, you might have ash build up or debris on the 90deg section, also check your clean out for the same thing, either climb up or check with binoculars the cap for a plug up, def sounds draft related.
Thanks. I gave it a look and it’s clean. Could there be a blockage in the stove itself? Is it with me getting on the roof today and checking it out? Thanks.
 
Thanks. I gave it a look and it’s clean. Could there be a blockage in the stove itself? Is it with me getting on the roof today and checking it out? Thanks.

I dont have your stove.. but I just ran into an issue with mine. My stove was not running correctly.. didnt seem to be drafting well even though for years I had plenty of draft and never had an issue with the stove. Last night I removed the LHS air manifold and vacuumed out the inside of the stove.. its burning more evenly in the box now and is behaving like normal.. the stove will not draft well.. nor run at normal temperatures of its not getting enough air and it will smoke because combustion is low..
If you run the stove and crack the door some... for a very short time and not over fire the stove.. will it run like normal..if it does.. you have an air restriction.. not a draft issue...
 
Just took a drone up to the cap... looks clogged to me as I can,t see any daylight. Thoughts?
[Hearth.com] Sudden Smoke Problem
 
Just took a drone up to the cap... looks clogged to me as I can,t see any daylight. Thoughts?
View attachment 273020

That would definitely cause smoke to back up!

...
-professional inspection/cleaning. He said all was fine and it was the wood we were using. (1.5year old self harvested oak)
...

I think I'd ask for my money back!

...
The cap is a pretty standard (I think) non screened, single flue cap.
...

Guess we have different definitions of 'non screened'!

Overall, that is a fairly poor cap design. That screen won't stop sparks / embers but will continually get plugged - as you can see.

A professional cleaning with some actual 'cleaning' would help. But my experience has been the screen can stay fairly clean but one accidental smoky fire (something like the stove failing to stay in a good burn when you go to bed) can plug it up pretty good.
 
Technically, not a reply to this posting and I'm glad your problem has been solved.

But just to add one other potential possibility that someone might find helpful down the road - I developed a smoke backup problem as well, but only on completely windless days with a lot of moisture in the air. Cold, foggy days were the worst. This all started happening in year 4 of our installation after no such issues previous. I was going crazy trying to figure it out. What I finally realized was that the radon remediation system we installed after year 3, together with the extra insulation we put in, was causing the easiest air replenishment path for the house to be right down the chimney and out the wood stove, but only under those specific conditions.

I solved it easy enough. Since I could feel the cold downdraft upon opening the stove door, on those couple days a year I make sure to leave the stove door open for an hour or two to let the pressures equalize. Once they do the downdraft disappears and I can run the stove with no issues.
 
Solved it today with a brush from the bottom.
[Hearth.com] Sudden Smoke Problem
I’ll get on the roof when the snow is gone and give it a proper scrubbing. Thanks for all the help.
 
Just took a drone up to the cap... looks clogged to me as I can,t see any daylight. Thoughts?
View attachment 273020
Clever way to inspect. As noted, there definitely is a screen in it. Looks like the stove is running too cool. Primary suspect, poorly seasoned wood. Is the liner insulated?