Could someone explain what combuster stall is? I see it mentioned fairly often but haven't been able to find any explanation of what it is, how to tell it is happening and what causes it. Thanks!
combuster stall
- Thread starter nagrod
- Start date
-
Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.
We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.
We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
stoveliker
Minister of Fire
it is the name for the instance where the combustor gets too cool and (therefore) stops combusting the smoke.
It is caused by e.g. choking off the fire too much, or when the fuel load is more or less gone (the latter is not a problem, the former is as smoke from smoldering will go into the chimney uncombusted after a stall).
It is caused by e.g. choking off the fire too much, or when the fuel load is more or less gone (the latter is not a problem, the former is as smoke from smoldering will go into the chimney uncombusted after a stall).
Thank you, that makes sense. I bought a new steel combuster, it seems to be working well but I occasionally get a condition where the chimney smokes and the Auber digital thermometer is reading 1000 degrees. I think that happens when the inlet to the combuster chamber is partly blocked by firewood pieces shifting. These things are a long learning process!
stoveliker
Minister of Fire
I sprung for two this Fall. One replaces the bimetallic one that comes with the VC Encore Flexburn and the other is in the flue about 18 inches above the stove top. This is my fourth burning season with this stove and I wish I had done it earlier because now I have a far better idea of what is happening and how to control the stove.
Woodsplitter67
Minister of Fire
If the 1000 degrees is on the combuster.. thats a good numbe4
stoveliker
Minister of Fire
I have times where the cat temps are 1000+ and there is still some white wispy smoke from the chimney. Stall to me is when I turn the air down too quickly and the cat temps will drop and not rebound like they usually do. I can do it on a hot reload some times, I'll have the cat pretty hot and good coals and reload the box flip the damper and cut the air and the cat temp will drop and not rebound. I'll open the air and see if I can get it to rise from there and wait to cut the air back.
stoveliker
Minister of Fire
Yes, that's a good description. A stall is any instance where the cat can't maintain its active state (due to lack of heat generated in the cat, or otherwise).
Woodsplitter67
Minister of Fire
stoveliker
Minister of Fire
Hm. That surprises me.
If indeed the 1000 degrees was on the cat thermometer, it should be working.
One possibility I was thinking about was that you. might have too much draft; then the time the gases spend in the cat could be insufficient for complete combustion, leading to smoke out of the chimney even if the cat is hot.
But at 15 ft that does not seem to be the case.
So, if indeed the cat is 1000 F, then I am stumped why you see smoke, unless the cat is bad/dead for some reason.
(And if the flue probe is 1000 F, then you're running (too) hot and the cat should be hot as well..., so I'm still stumped.)
If indeed the 1000 degrees was on the cat thermometer, it should be working.
One possibility I was thinking about was that you. might have too much draft; then the time the gases spend in the cat could be insufficient for complete combustion, leading to smoke out of the chimney even if the cat is hot.
But at 15 ft that does not seem to be the case.
So, if indeed the cat is 1000 F, then I am stumped why you see smoke, unless the cat is bad/dead for some reason.
(And if the flue probe is 1000 F, then you're running (too) hot and the cat should be hot as well..., so I'm still stumped.)
Woodsplitter67
Minister of Fire
your draft should be ok even though its a little on the shorter side. How old is the cat.. ceramic or steel. what stove.. 2040.. 2040 c cat.. Defiant
When the cat goes above 1000 does the smoke stop? As I said if I close the damper and the cat goes up to over 1000 and I go out and look I will see white smoke. After a while the smoke stops all together and I might see the heat waves from the chimney.
Last night I stalled my cat after a hot reload, had tto open the air and get the heat up and then close it back once it went up in temperature.
Last night I stalled my cat after a hot reload, had tto open the air and get the heat up and then close it back once it went up in temperature.
Yes, the smoke almost always stops in a few minutes. Occasionally I've had a problem but I think it's my own fault, not getting a good enough bed of coals down. When I do a hot reload I leave the bypass damper open for a few minutes and sometimes the primary air damper also until the new load is ignited. I always keep an eye on the flu temp. when I do that. It is a new steel cat this season, replaced my original ceramic one. I'm happy with it, but there is a lot to learn.
