A fluttering flame?

[LIpelletpig]

Ok here is my issue....I am running a Harman Accentra Insert with a full 25' vent up the chimney. Ran the stove for 1-year now with no issues. Recently installed a OAK to the stove with a 3" aluminum tube up the stack a few feet. I installed (2) intake 2 1/2" pipes at the top of the chimney. The issue I've been noticing is the flame burns strong 95% of the time with no issues and then I get a fluttering flame it could last anywhere from 5 seconds - 15 seconds or more. I keep this stove spotless and I've checked all vents at this point and have not noticed any issues. I removed the OAK tonight and it seems the stove is running a little better without the fluttering. I am not sure what the issues are at this point and was hoping someone can help me on the forum. I do realize we do get a little flutter in the flame when the pellets are being fed into the burnpot but this is note the issue. I've also gone to the top of the chimney to see how the pull is for air while the stove was running and I felt no pull. This could be because it such a long run and the 3" OAK pipe does not extend all the way up the chimney. So the pull could be very little by the time it hits the 25' mark at top.

I know the OAk is suppose to help with cold drafts in the home through windows and doors. My 2nd question is with the distribution blower on HIGH doesn't that pull air from the living space stronger then the cumbustion fan and create a draft within the home through the cracks anyway?

Here are pics of the OAK install

https://www.hearth.com/talk/threads/41401/

 

[GVA]

Sounds like woofing...
Does it make a low rumble while it does this?
Search for woofing if it does

 

[imacman]

Med, I remember your pics of the OAK install. Personally, I think 25' for an OAK is pretty far.

As for the fluttering, is it possible that it happens with the wind blowing in a certain direction, or speed? Maybe it's causing the pressure to fluctuate, thereby causing flutter?

The distribution blower in the home causes NO change in the interior...it's taking the air from the same place it's blowing it to....

 

[LIpelletpig]

Thanks for the replies. I am going to try the tape trick and see how that works. Macman the manual for the Accentra suggests to do the OAK this way so it must work successfully. I went the up the fireplace route vs. going through the back of the firplace to the attached garage. I just have to fuss with it more and see how we do.