Creosote Question

[Alex C]

Been burning about a month now. I generally have good hot startups to 650 or so, then dial it down and it does it's thing at about 400. The flue temp gets up to about 500 on startup. I have an old mill stove with a baffle that has a top exit and from there it's a straight shot right out of a cathedral ceiling. Lately I have heard sizzling right around a foot up the flue where my thermometer resides. Does anyone think it's creosote liquifying and burning? I don't believe I have a leak and there's no way water would get that far down the flue at 500 degrees. Any ideas? Are chimney fires only likely at start ups? My wood isn't perfect but my guess is around 20% mc.

 

[begreen]

Sounds like the wood. Next time open up the stoves after fresh splits have been added and see if the sizzling coming from the ends of the splits. If the run up to the support box is single-wall it probably is compounding the problem by cooling the flue gases too much. When was the chimney and cap last cleaned?

 

[Alex C]

Sounds like the wood. Next time open up the stoves after fresh splits have been added and see if the sizzling coming from the ends of the splits. If the run up to the support box is single-wall it probably is compounding the problem by cooling the flue gases too much. When was the chimney and cap last cleaned?

I can just about guarantee that the sound isn't the splits. It's up in the pipe, you can almost feel it when you get right close to it. The splits don't steam but occasionally excrete foam. Just got some much dryer wood and it is still sizzling a little above the collar.

 

[bioman]

Give a good cleaning & see if it stops.

 

[fbelec]

that foaming is the wood is not dry or seasoned enough. that foaming is creating creosote in your pipe and the noise you hear is it starting to burn. sounds like you need to find wood that does not foam or hiss and you need to clean out that pipe. if you continue you will have a chimney fire. also if that 400 is stove top temp you need to come up to 500 or so running temp. if it's not a stone stove and built out of steel or cast iron i would be running it at 600 to keep it cleaner burning.

 

[BrotherBart]

Yep. Been there, done that. The sound is the moisture cooking out of the creosote in the pipe. When it dries out you don't want to see what happens next.

Where are you reading that 20% moisture content on the wood?

If you are only seeing 500 in the pipe when a new load cooks off then that stuff is wet.

 

[FishKiller]

I completely agree that's not your wood hissing, its the moisture cooking out of creosote buildup. i really get really annoyed when i come across a split that hisses or bubbles because i put some much effort into seasoning and drying my wood (although every once in a while i find a split that the wife stacked on the wrong pile to "keep things even"). you need a good cleaning and you need to change your burning habits. slowing it down to 400? that's way too low. i'm not an expert and i just do what i feel makes my stoves run happy and clean. i run them "low" at 550-600 depending on how recently i reloaded. startups spike to 750+ (never let it glow though). but please, before you change your habits and allow the stove to run right, clean your pipes trying to run it hot now will only lead to a fire.

 

[fbelec]

alex how are you making out?