No gasification w/Biomass 80

[jaoneill]

Any thoughts would be most welcome. I've had the 80 fired for a few weeks now with no issues whatsoever. Burning dry elm (12%-14%) split small (2"X3-4" ends), and have had a nice orange glow in the sight glass any time I have checked. Was running the fan @ 70%, shutter at about the halfway point, primarys wide open, secondary open about 1/2".

Today it turned cold (10-15) with 30mph winds and this afternoon the bloody thing won't fire.

Upper chamber is burning nicely, bed of coals up to the air slots, but natha for gasification. I have tried increasing fan speed, stirring coals, readjusting primary & secondary air all to no avail. A few minutes ago I stirred the coals under a raging fire in the upper chamber and when I closed the door, low and behold she was gasifying. After a few minutes it stumbled (like an oil gun with air in the line), spit and sputtered and the glow in the gasification chamber quit. What the h*ll??

 

[Hydronics]

I would verify that the nozzles aren't blocked with an ash clinker. Work a poker around through the bottom of the nozzles until red coals fall down. Be careful not to burn your hands. You could also work the poker from the top if wood isnt in the way. Also verify that the bypass is closing all the way.

 

[jaoneill]

I would verify that the nozzles aren't blocked with an ash clinker. Work a poker around through the bottom of the nozzles until red coals fall down. Be careful not to burn your hands. You could also work the poker from the top if wood isnt in the way. Also verify that the bypass is closing all the way.

You nailed it Hydronics! I had been working the poker from the bottom all afternoon/evening, getting coals, but to no avail. Just after I started this thread I hit it from the top, working the poker all the way down through the nozzles. It must have freed up the clinker; it's working like a champ again. Another lesson learned….. A heartfelt Thank You…...

 

[Hydronics]

Glad you're back up and running. At some point, you'll want to let it burn out and clean out the ashes in the upper chamber or it will happen again.
I find that I get the best gasification when the ashes are cleaned out allowing the refractory to get as hot as possible.

 

[jaoneill]

Glad you're back up and running. At some point, you'll want to let it burn out and clean out the ashes in the upper chamber or it will happen again.
I find that I get the best gasification when the ashes are cleaned out allowing the refractory to get as hot as possible.

We had intended to be away for a couple of days so I had let it essentially burn out yesterday morning. We hit the lake effect snow just south of here and had to turn back. When we got home I cleaned out most of the ashes, leaving a shallow bed of live coals over the nozzles to facilitate the startup. There must have been an "ash cake" under the coals

Thanks to your advice last night, I now know what to look for. Although I had it working again, it was just random luck. Without your advice I wouln't have known what the problem was; now I know what to look for if it happens again….