Sealing Cleanouts and Smoke

[runnerbeanfarm]

Questions:

I have been having a problem completely sealing my cleanouts. A little smoke is seen when the fire is just starting or at the very end of a burn. Do you have any suggestions?

Also, how paranoid should I be about fumes seeping through cob? The bends I used were adjustable and leaked like a sieve until I put some fire cement on the joins am a little worried that they may still leak a little.

Background: I built a 5” system in our 16’ earth yurt. The combustion unit is built out of fire brick insulated with pumice and then surrounded by sand clay cob. The flue is run in a “U” in the floor and then up and through the wall to a vertical stack.

[Donkey]

To your cleanouts: dunno how to help since I dunno how they are made..
I've got some cleanouts on my stove with cob doors.. To seal them I just use a thin schmear of cob with chopped straw (more like a straw clay plaster) around the edges. It needs to be scraped away and re-applied when using the cleanouts. It can be an annoying process, though it only happens once a year or so..

Be paranoid.. Until you KNOW differently, paranoia can be a good thing.
It's my feeling that seepage through cob shouldn't be an issue.. I have not experienced any such problem with mine and I have sections made purely of cob. Still, you may wish to get a CO warning gizmo and place it somewhere nearby just to be sure.