Type 3 creosote

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Aug 6, 2018
I’m not new to having a wood burning stove (grew up with 2 old Buck Stoves) but new to looking at it past, “house is cold, build a fire.” This is the first time cleaning my chimney myself. About 22’ tall Kozy Heat Z42 as the stove. There was lots of bubbly crust on the outside edge of the chimney that got me up there. After I cleared maybe 2 cups of that out I thought it was good as the chimney itself was open and clear, just a slick black layer. Will my one of the FB groups told me how bad it was and I was doing something wrong. I 100% understand the fire hazard but can’t find out where I’m going wrong with my burns. The wood is all dead, aged and covered (roof and tarp on the windward side). I don’t have a thermometer on it or measure wood moisture. I do try to get it going well, up to temp to kick on the blower, then neck it down a touch so it’s a solid fire but not heating us out if the room. I guess my question is does type 3 creosote happen to most chimneys and just clean it or try a good fire to get it hot? Is a creosote log worth a try?

Type 3 creosote
Glaze creosote is serious and a symptom of a problem. The most common culprit is damp wood. Sometimes seasoned wood can get wet due to a leaky tarp covering or the wood sat on the ground for too long.

You could try burning with some cre-away and see if that puffs up the glaze, then sweep again to remove it.
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Sometimes tarps can do more damage then good, top cover is great, side cover can create a moisture sponge, especially if the top cover has a small leak, or the ground underneath is not easily self draining / drying.
Best to spend $25 on a moisture meter, take a split at room temp and re-split it, test the fresh face to get an adequate reading.
An insulated liner is also a good thing, it should keep flue gases warmer (above 250 deg f) which keeps the smoke from condensing and causing this type of creosote. If your liner is insulated, then burn hotter and sweep more frequently.
I had level 3 creosote in my chimney liner. Caused by me burning inadequately dried wood low and slow in my old wood furnace. I changed out the wood furnace for a modern wood stove. The following winter I used a few pounds of Rutland powdered creosote remover. Just a spoonful on the coals before a reload. Swept the chimney (from the bottom) halfway through the winter and again in the spring. Then I got up on the roof to inspect the chimney. Thank goodness, all that black tar creosote was gone.

Since I now dry my wood for 2 years and have modern stoves, zero creosote issues at all.
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I clean my pipes monthly. Only a little black powered soot.I use a shop vac and a brush. Its like a 20 min job, so why not?