Low Thud Thud sound from my Lopi Leyden?

[avanderheuel]

So my stove is making this thud thud sound every 15-45 seconds. Sounds like the wosh or thud gas makes when you put it on a camp fire but not as loud...

Thoughts?

 

[begreen]

Maybe backpuffing? Is the stove pipe dampered down?

 

[drewmo]

Sounds like you've dampered down too much too soon. Get a good fire going and slowly cut the air. Should result in a good secondary burn.

 

[branchburner]

I get the same with mine if I close the air down quickly instead of stepping it down in stages.

 

[Troutchaser]

At what point of the burn do you hear it?
What is going on in the firebox?
Is it a thud? Or a "whoosh"?