Is this normal?

[Timebandit]

I have dis-coloration at the very top of my metal chimney. And the cap is looking black. Only been using the stove a few weeks. Any clue?

 

[DAKSY]

Wet wood...Incorrect burning techniques...Maybe both?

 

[mikepinto65]

After reading all your other posts concerning stove operating temperatures I think this is the icing on the cake.....your wood is not seasoned all the way. The reason why you are getting black at the cap is because your fires are not burning the smoke (due to under seasoned wood) and creosote is showing its presence. I have a feeling you are probably seeing some secondaries before tuning it down for the nightly burn, but suspect that during the long hall of the burn it snuffs itself out and smolders. With under seasoned wood you can get the stove temp to 500 but once the air is cut down 90% of the time the fire will snuff and you'll get a smokey mess with temps dropping to 300-400.

 

[mikepinto65]

P.S. dont get discouraged, its happened to us all....your just gonna have to run it with more primary air (and keep a close eye while doing so) and start planning now for next years wood.

 

[Timebandit]

No dont think its wet wood. Less than 20% moisture content. I have never had the stove up ovr 425 dgrees. I dont think my burning technique is wrong either. Start with lots of newspaper and nice dry kindling(i think thats how you spell it). Fire burns nice. Any advice?

 

[Jags]

I have never had the stove up ovr 425 dgrees.

I think I see your problem.

 

[mikepinto65]

No dont think its wet wood. Less than 20% moisture content. I have never had the stove up ovr 425 dgrees. I dont think my burning technique is wrong either. Start with lots of newspaper and nice dry kindling(i think thats how you spell it). Fire burns nice. Any advice?

Right youve said that in your other post but you never answered a previous question....did you take the mc from the end of piece of wood that was split in February or did you re-split a piece and take the reading from the core? Also fwiw, not that this'll help you, oak split in Feb is not seasoned and ready for burning.

 

[Timebandit]

I took the reading from an old split. The splits are thin, not to thick. If this is my problem , will i have a chimney fire?

 

[buffygirl]

Timebandit -- I'm a new Jotul Oslo burner and unfortunately I'm trying to learn how it operates -- the book(s) which came with it are useless -- but many opinions have come my way to which I'm thankful -- there is a post on 11-3 from bluehawk with many replies about stove top temps which is very informative -- Check it out and best wishes.


Buffygirl
New Jotul Oslo Fall 0f 09
Old VC Cat retired after 19 years.
Stihl Chainsaw
Still Split with axe

 

[rdust]

I'm sure all stoves are different my steel stove likes being around 600*, fresh wood loaded on a nice bed of coals and it's near impossible for me to keep it going that high. I start backing down the air around 400* and the temp. really starts to sky rocket after the secondary burn starts up.

425 seems cold to me but I don't know your stove so it may be correct??

 

[Jags]

I took the reading from an old split. The splits are thin, not to thick. If this is my problem , will i have a chimney fire?

I think Mike is trying to figure out your "method" of testing the split. The split needs to be RE-split at the time of testing. The newly exposed area is where you need to test at.

This doesn't mean that you WILL have a chimney fire, but abnormal creosote production will increase the dangers. Proper stack maintenance will mitigate this as well as the easy thing - and that is to burn cleanly with properly seasoned fuel.

 

[mikepinto65]

I took the reading from an old split. The splits are thin, not to thick. If this is my problem , will i have a chimney fire?

I think Mike is trying to figure out your "method" of testing the split. The split needs to be RE-split at the time of testing. The newly exposed area is where you need to test at.

This doesn't mean that you WILL have a chimney fire, but abnormal creosote production will increase the dangers. Proper stack maintenance will mitigate this as well as the easy thing - and that is to burn cleanly with properly seasoned fuel.

Right-O

 

[rdust]

I took the reading from an old split. The splits are thin, not to thick. If this is my problem , will i have a chimney fire?

Splits need to be re-split to check them. If the chimney isn't kept clean, Yes a chimney fire could happen. Even burning less then ideal wood if you keep the chimney clean you should be fine, plenty of people have done it.

 

[Pagey]

I think it would be wise to check your chimney for buildup. I have a discolored spot on about the last 1/3 of the final 3' run of my exposed Class A on the north facing side. This discoloration, I assume, has to do with heat and prevailing wind direction. I check for creosote buildup routinely, and I sweep routinely (pretty much monthly during burning season), and I've never had any excessive creosote problems.

So your discoloration COULD be unrelated to actual creosote buildup, but to be safe and to gain knowledge, you definitely need to check it.

 

[mikepinto65]

I think it would be wise to check your chimney for buildup. I have a discolored spot on about the last 1/3 of the final 3' run of my exposed Class A on the north facing side. This discoloration, I assume, has to do with heat and prevailing wind direction. I check for creosote buildup routinely, and I sweep routinely (pretty much monthly during burning season), and I've never had any excessive creosote problems.

So your discoloration COULD be unrelated to actual creosote buildup, but to be safe and to gain knowledge, you definitely need to check it.

Discoloration is one thing and I agree with you, black is another and so I sort of disagree with you too

 

[Pagey]

I think it would be wise to check your chimney for buildup. I have a discolored spot on about the last 1/3 of the final 3' run of my exposed Class A on the north facing side. This discoloration, I assume, has to do with heat and prevailing wind direction. I check for creosote buildup routinely, and I sweep routinely (pretty much monthly during burning season), and I've never had any excessive creosote problems.

So your discoloration COULD be unrelated to actual creosote buildup, but to be safe and to gain knowledge, you definitely need to check it.

Discoloration is one thing and I agree with you, black is another and so I sort of disagree with you too

LOL, and I agree with you! My cap's not black. I'd definitely check things out of the cap is black.

 

[Timebandit]

Thank you all. I will be sweeping my chimney.

 

[edthedawg]

As stated before, you need to run it hotter, too. You cannot be staying below 425F and running properly. the two DO NOT go together.

 

[brokeburner]

discoloration means that it has been hot enough to heat the metal to red or dull red. When it cools down you get discoloration. What color is it? Does it have a blue tint to it.

 

[mikepinto65]

discoloration means that it has been hot enough to heat the metal to red or dull red. When it cools down you get discoloration. What color is it? Does it have a blue tint to it.

Read the first post here...
Regardless of the metal the cap is black

 

[Timebandit]

yes brokeburner there is a hint of blue from what i can see

 

[firefighterjake]

I have never had the stove up ovr 425 dgrees.

I think I see your problem.

My thoughts exactly Jags . . . first thing I picked up on.

Run the stove hotter . . . 425 isn't really all that hot. I regularly run my Oslo up to 500-550 when I want to go into the disco inferno zone . . . it may sound counter intuitive, but running hotter (within limits) is actually better for the stove and flue.

 

[mikepinto65]

I think the OP mentioned in another post that he cant get the stove up that high. Even if he can, if the wood isnt seasoned, as I highly suspect, the firebox will never hold enough heat to sustain the temps needed for secondary combustion with the air cut back. Im simply going with this because i've seen it first hand in my Oslo with wood mixed in my pile with 28-30% MC. I can preheat the piss out of it but once I back the air down (with too many of those pieces loaded in) its lights out...

 

[meathead]

just going by my f600, 400-425 is right on the cusp of running clean with that thing. We have temps that are probably similar to yours where I am...and this time of year with temps in the 40s to low 50s I frequently see my stove slow down into the 400 - 450 range with good secondary still kicking and no smoke out of the chimney. That being said, I load pretty big splits, and it still kicks over 500 for a little while with every stove load. Plus, if at any given time I open the air up, it will take off into higher temps. When things get down into the 10s, 20s, 30s, the stove will run over 500 all day and kick over 600 or 650 every load.

I'd say first and foremost check your chimney and see if you have any buildup. Then when you have some time around the house, load up like you usually do and let the stove settle into where you have had it cruising. When it is cruising where you normally have it, go outside and see what's coming out the chimney - you shouldn't see much more than heat waves (no smoke).

 

[quads]

No dont think its wet wood. Less than 20% moisture content. I have never had the stove up ovr 425 dgrees. I dont think my burning technique is wrong either. Start with lots of newspaper and nice dry kindling(i think thats how you spell it). Fire burns nice. Any advice?

Right youve said that in your other post but you never answered a previous question....did you take the mc from the end of piece of wood that was split in February or did you re-split a piece and take the reading from the core? Also fwiw, not that this'll help you, oak split in Feb is not seasoned and ready for burning.

Your oak is not ready. Small splits will help, check your chimney at least once a month and clean as needed.