high-functioning catalytic, but smoke from chimney

[RustyShackleford]

My stove is in about its 5th year of burning and I think the catalytic combustor is in good shape - comes up to temperature quickly, stays active for well over 12 hours of burning with a good load of dry wood. BUT ... I've got lots of smoke coming out the chimney. Last night the cat temp was pushing 2000 degree and there was visible smoke; right now it's 1800 and the same.

What is up with that ? Could it be as simple as a leaky gasket around the bypass door ? Or can a worn-out cat be getting those kinds of temps but still letting smoke through somehow ?

 

[begreen]

Could this be steam instead? Is the "smoke" grey or white? Does it dissipate quickly or does it linger? If white and quickly dissipating, it's steam. If grey and lingering it's smoke.

 

[RustyShackleford]

Could this be steam instead? Is the "smoke" grey or white? Does it dissipate quickly or does it linger? If white and quickly dissipating, it's steam. If grey and lingering it's smoke.

Good thought, thanks. Hard to tell right now against this grey sky; I'l pay more attention when the sky is blue in a few days. I think my wood is pretty dry though - I've managed to get to where it's cut and split and stored under a roof at least a year-and-a-half in advance now. Plus, I don't think I'd be holding fires this long if it wasn't mighty dry - I've been keeping the cat active for up to 18 hours, coals able to easily re-ignite a fire for 48 hours.

 

[Burner]

I notice that sometimes my cat stove gets overwhelmed by having too much smoke going through the Cat. This only happens oddly with very dry wood. Wood at 20% moisture doesn't seem to generate as much smoke. I also notice that there is a big difference between Cats. I replaced a cheap one with a Condar and even though the cheap one was getting up to temps, it didn't burn nearly as cleanly as the new Condar cat.

 

[Highbeam]

Normal. Mine does it too and always has. Cat glowing bright orange and still smokes. No stealth burning for me.

The smoke will come and go it is usually blue and pretty easy to see through. The smoke is worse with a fresher load and seems to be less when the stat is satisfied. Some days I also get steam which is very obvious and even happens with very dry wood as a byproduct of combustion. 10% moisture content is still 10% moisture that has to go somewhere.

 

[RustyShackleford]

... even happens with very dry wood as a byproduct of combustion. 10% moisture content is still 10% moisture that has to go somewhere.

Oh yeah, sure. Even 0% moisture-content wood is going to generate steam - the basic chemical equation of burning the methanol.