Chimney smoke color

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burntime

New Member
Hearth Supporter
Aug 18, 2006
2,395
C'mon hunting season!
Hello all,

I noticed today that when I get a fire going really well and damper down the insert I get a more white-ish smoke, almost like steam. I am getting good secondary burn. I have a masonary fireplace with a full stainless liner. The fireplace is in the middle of the home. The liner is not insulated. Could the color be due to an uninsulated liner? Wood is 17-21% per the harbor freight gage...yes I split it first to check. Any ideas from the experts or is this normal? Temp today was somewhere arround 10 degrees.
 
it would be normal when you dont have complete combustion. even though your getting secondary combustion, you not burning all of it. SO lots of possiblilies exist. You have to strong of draft, the chimney is sucking out the flue gas before it can burn it. Another is that you are looking at the stack when you add wood or just started up, a mature fire in that appliance should not smoke. another would be that you have it damped down to much, and its not hot enough to burn everything.
 
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Its a hampton HI300, if I open it up a little I have only a shimmer without any color at all. I take it that would be the most efficient operation...with the damper open just slightly?
 
Generally, white smoke is mostly water vapor evaporated out of the wood. It's normally seen reloading or starting fresh, if it persists through the burn you have very wet wood. Blue smoke is bad, it's incomplete burned fuel and adding creosote and wasting energy.

On reload or start-up I tend to get more white smoke and eventually it shifts over to a bit of blue which doesn't last long, and then if things are right my chimney looks like clear heat waves coming out. If the burn has been going on for an hour and I go outside and see a hint of blue smoke coming out I'm not getting complete combustion and turning up the air a little fixes that.
 
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Thanks, you guys are great. I appreciate your help.
 
I find my damper has to be open slightly also, if it is push it all the way in I do get some smoke from the chimney. I also find the secondary burn seems to go out with in a few hours even though there are still good size pieces left in the stove. I’m still learning the proper balance for my stove and so far having the damper out a little gives me the best results and longer secondary burn time.
 
My stove puts out white steam also. I thought it was smoke at first, but later found out when you are close to complete combustion all that is left over is water vapor. When it comes out of the chimney it looks like white steam and dissipates quickly. Kind of like seeing your breath outside when its cold.
 
You should study how the air handle affects the speed at which the flames rise compared to how much smoke and the effects. Once you've mastered what flame speed your unit operates best at, you'll be well on your way. I'll warn ya, it takes a year+. I've found generally the air handle for best burn is around the same spot but sometimes it's higher and sometimes lower, on occasion much higher/lower than normal. But, I've learned what speed I want my flames to leave at, and if they're slower I know I'm getting incomplete burn and smoke, if faster the heat is going out the flue. I guess you'd call it the sweet spot. BTW that's after the unit's up and running and you're ready to turn down the air. I turn it down in steps, it doesn't like going from max air to like half in a single move, I turn it down 25% give it a few minutes and then turn it down again looking for the flames rising at the speed I know it works best at, there's too many other variables at play otherwise. Or, a thermometer would probably make it easy.
 
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