Chimney cap discolored

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cwfirefighter01

New Member
Nov 22, 2021
4
Kentucky
I’m new to wood burning so any advice helps. We just installed our Drolet Columbia 2 with 16 feet of Security stove pipe straight up through our attic and out the roof. 3-2-10 rule was followed. Double wall interior, triple wall through attic out the roof. We just passed the break in period of our stove and had several big long burning fires. We usually burn of the evening and let them burn out over night after putting fresh wood in before bed. Our chimney cap is now totally black and brown colored And the top of stove pipe near the cap is bluish color. We live in Kentucky and the temp outside varies the past few weeks from upper teens to upper 40s at night. Our wood is dry according to moisture meter readings below 18%, Have we got our Chimney cap and stove pipe to hot or what is the possible issue? Is it damaged? Below is a picture of our stove.

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This is the stove pipe and cap.

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Kudos for a nice installation. Is the air being turned down progressively as the fire gains strength?

The best way to know how the stove is burning is by the flue temperature. A probe thermometer is required for double-wall stove pipe. It will let you know how much heat is going up the flue.
 
The rainbow colors on the pipe are normal, mine does that too, it's just some of the flue gases condensing on the outside causing that.

My chimney cap never turns completely black however, brown and discolored, but never black. Mine always washes off with rain, by fall my cap is shiny again like new.

It's possible you're burning a little cold or your woods on the wetter side. But you've said your wood is dry, so it is possible to burn so hot the stove produces soot. Run the stove and see what smoke comes out, white, blue or black, this makes diagnosis easier.

Ultimately stoves do emit some particulate that discolors the cap, it's the nature of the beast. I don't know anyone that burns full time whose chimney cap stays shiny.
 
Thanks so much for the help. I do try to turn the stove air intake down as the fire gets hotter and let it burn out overnight. I’ll burn it and check the smoke color. I was just worried that I ruined my cap and stove pipe by possibly running the stove too hot. This has been a learning curve for sure but this forum is awesome and so helpful.
 
Some instrumentation is very helpful.
 
We never had that much "black" on the glass of our Columbia II. We rarely had any at all except for a wee bit in the bottom corners from time to time. I don't think you are too hot. I suspect you are a wee bit cold. And your chimney looks normal, if a bit too black.. As mentioned, a probe thermometer and also an IR gun will tell you most of what you need to know. SBI (who owns drolet and other brands) has a tidy probe thermometer that isn't all multicolored and obtrusive. It's also quite reasonably priced.

we really liked our Columbia, but found it a little small for our severe climate. It made plenty of heat, but required lots of tending in very cold weather. We now have a much bigger Drolet that has more room for wood and ashes/coals. We are very satisfied with both of our Drolet's.
 
The set up you have lokks great.. nice job. The outside looks normak as far a color. You will get some black on the cap, this is expected as 1 when you start the stove you will have smoke because its a cold start. 2 the cap and stove pipe are not up to temperature because its a cold start and some creosote will form. You should do an inspection here and there because your new and getting acclamated to the stove. Its also a great idea weather your now or experienced to have some probes/thermometers on a stove or stove pipe
 
A black cap after a few fires is soon. Did you measure the moisture content on a freshly split surface so you get the mc from the inside of the split rather than the dried outer parts of it?
 
Thanks again for the reply’s. I will split a new piece of wood and check the moisture reading that way and see what i come up with there. I do have a stove top thermometer, i try to watch the fire and the readings on top of the stove as it burns. Ive read a lot of mixed reviews on the probe thermometers as well. I do have a double wall stove pipe. Some of the reviews I’ve read stated that a stove top thermometer and a glass door is all you need. Any comments on this topic would be appreciated as well from you experienced guys.
 
If you want to know what happens to your chimney, you need to measure in your chimney...

It also tells you how efficient you burn, because the heat produced goes two ways, in your room and in your chimney. Stove top temps don't tell you much about these two, and are slow as well (a lot more metal has to heat up before they register an increase in temp).