Is this not good? Dangerous?

Perhaps a dumb question but…..

Let my fire go out today, calling for very warm temps the next few days, plus I gotta fix up a few thing. Noticed this inside the fire box, it’s like greenish and soot like. Wipes right off, but just wondering if this is bad? Like if I started a wood fire in it should I be concerned?

Thanks!

I don't know about the color, but I don't think it would be dangerous to burn wood with that stuff in it.

I assume you are concerned about a chimney fire, bituminous coal doesn't make a highly flammable creosote. It can make fluffy soot that sorta kinda almost burns or sublimates under extreme heat. However it's nothing at all like creosote burning.

If you're worried about it scrape some off and attempt to catch it on fire, I bet that you might be able to get it to glow a little bit an then it goes out.

Thank you! I almost think it’s just silver smoke residue, and as far as the color I think it’s a mix of the yellow on the black interior. Yeah I just was concerned with how much might be in the stack and I didn’t want to end up with a flame thrower outside .

It does just wipe right off, almost imagine a nice wood fire would clean it right off.

Thanks again!

Dfmihm wrote: ↑

Tue. Nov. 14, 2023 5:47 pm

Like if I started a wood fire in it should I be concerned?

I can't comment on that but the opposite can be true. There is two issues with wood creosote when switching to coal. The coal will dry it out and it can fall off in big pieces potentially blocking the flue, at least that is the case with anthracite and I would assume same issue with bit.

The other hazard is if you install a barometric damper and don't remove the wood creosote, if you have a chimney fire it's on steroids with a perfect source of air. Typically this would only apply with people switching from wood to coal with a heavy amount of creosote buildup.

I don’t have a damper. Only had a few wood fires in this so far this year, and really I try to only burn enough wood to get it hot and ready for coal. And the wood is seasoned too, but I know creosote can still build up. After my first couple fires, the inside of the pipe from boiler to chimney was still silver (was brand new) and just cleaned the chimney and vacuumed. So far the only big piece of anything that I seen was a chunk of rusty scale from the very top of the boiler during the first fire .

Thanks though, good knowledge to have and know to at least keep an eye on it. Appreciate it!