Secondary burn problems I think solved

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ddahlgren

Minister of Fire
Apr 18, 2011
555
SE CT
I have been battling this since the end of last season. Before that I had epic burns that got the whole house in high 70's to low 80's if I wanted them. I think wood and re-split to check and 16 to 17% so should be fine. I checked gaskets with both a dollar bill and smoke and nothing shows bad. So I play with the alignment of the holes in secondary air tube and as original still best. I looked every where for cracks or air leaks. I even tried 1/2 in wide strips of newsprint between door gasket and stove and every piece tight enough to rip. Had the chimney cleaned and that was 75 bucks wasted as virtually nothing in it.

My normal procedure is the get the stove up to 500 on the top and probe at 700 while closing the air down in steps and fully closed at that point. I get secondary's but only for a few minutes then the go out and probe starts going down to low to expect them to be burning..

S I came to the conclusion there are only 2 places air can get in the door gasket that I checked and passes and the secondary burn tube where it is supposed to come from so must be the wood and maybe meter is lying. So tonight I loaded 7 bio bricks loosely in stove stacked with plenty of air space and very dry kindling. Got the stove top above 650 and the probe around 900 before fully closing. Great secondary's that last under 5 minutes they go out. I got the stove and probe way up there again and watch the secondary's to see what I can for clues and out the corner of my eye something odd popped up. There are flames at the bottom of the door so I have to think the gasket that tested good leaks. I tried fo a cell phone picture but it just did mot work.

Now I have to find some 7/8 gasket materiel. All the door gasket tests at least for this stove don't tell the whole story I guess.
 
Rather than the dollar bill test, I sometimes find it easier to light a match and hold it near the suspected air leak (while the stove is burning). If the match flame is sucked in, you found your leak.Smoke test seems less reliable.
 
I would think that if the fire is dying down to quick and your loosing secondarys that quick, an air leak is not your problem. What is you chimney set up? I rarely get the awesome secondaries that everyone speaks of for very long (5-15 minutes) but if the flame is dancing in the upper part of the firebox and not directly off the wood then you know its the gases burning off and you are getting a secondary burn. From your description it seems as though you not getting enough air. How tight is the house? Is draft good enough to pull air into secondary tubes? Do you have an OAK?
 
I would think that if the fire is dying down to quick and your loosing secondarys that quick, an air leak is not your problem. What is you chimney set up? I rarely get the awesome secondaries that everyone speaks of for very long (5-15 minutes) but if the flame is dancing in the upper part of the firebox and not directly off the wood then you know its the gases burning off and you are getting a secondary burn. From your description it seems as though you not getting enough air. How tight is the house? Is draft good enough to pull air into secondary tubes? Do you have an OAK?

That could be argued except for the fact it is the same chimney as last year with the same stove plus it is much colder this year currently 9 degrees as we speak. I had secondary burn for hours last year on a 30 degree night. Even though very short it pulls very hard and makes 0 creosote. The house is 1874 and pretty much original. I am thinking the leaky gasket is short circuiting the secondary air tube and makes perfect sense to me. I will try cracking a window next to the stove and see if it from lack of combustion air just for fun.
 
Could be your wood what I've noticed with mine is the dryer the wood the quicker I can close the air and get the secondaries going. The wetter the wood ( meaning seasoned but the ends may be wet from outside) the slower I will have to close the air down. I have a little stove, I only get the tubes burning for about 5 min then the flame dances the rest of the time...good luck.

Don't know your stove but if you have glass door just watch it...that will tell you if your to soon on closing the air down...always works for me.
 
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