Creosote question

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Oct 23, 2013
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SE Mass
Hi. I've been a lurker here for about 8 months. I have learned a ton on this forum so first off I would like to thank everyone on here for all the information I have gained.

Next is my newbie question...

I had a Regency I2400 wood burning fireplace insert installed late last winter. They installed a 6" flue liner at the same time. I burned for about 6 weeks with it last season. Burning season is about to start here, so I checked with the shop that installed it to get the flue swept just so I could get an idea of how it looks after 6 weeks of burning. I am new to burning, but I have tried to use the info I have gained here and have only burned dry hardwood (checked with a moisture meter to be less than 22% - mostly oak around 18%.

The chimney sweep at the shop said not to bother getting the flue swept (?!?) and to wait until about 3 months into this winter to have him sweep it. I said i want to make sure things are going well and he said if I wanted I could pull down the fire bricks in the top of the stove and see what the ash looked like. He said some ash should have fallen down the flue from it sitting dormant all summer. He said if it was all fine powder I was all set but if there was big shiny chunks then it is a bad sign.

I pulled down the bricks and there was a small pile of black ash. It was all pretty fine, but some of it was shiny. I was surprised because all of the ash I have taken directly out of the firebox has been pure grey. I took some pictures of the ash on the fire bricks and a picture of the flue liner where it enters the insert.

What do you guys think? Is this normal? Should I get it swept now? Is that a layer of creosote on the flue liner? If so, how bad is it? I am paranoid about getting a chimney fire.

ash.jpg


flue.jpg


Thanks!
 
Anyway you can get in there to look right up the flue with a bright light?

How about getting up on the roof and looking at the cap and the top few feet of the chimney (where a majority of creosote accumulates since it's the coldest area)?

Any thought to cleaning the chimney yourself?

I'm going to move your question over to the hearth room for better response to this sort of thing.

Welcome to the site!

pen
 
Judging by the ash in your first pic I think everything is ok. Mine is flaky when I sweep it and yes that is a good sign.

I also second Pen's suggestion about cleaning the chimney yourself. As long as you don't mind getting on the roof it really is an easy job, especially if your chimney is straight like mine. I clean mine once a year and it takes 10 minutes tops.

Also, if your chimney is straight you can get a small mirror and put it in the bottom. You should be able to see all the way up the chimney to the hole at the top. If you can't see the hole or only part of it that tells you that there is a blockage that needs to be cleaned out. I check mine weekly because I'm paranoid too but with the mirror that takes 1 minute.

Finally, if there is a blockage, you should notice smoke coming out of the stove into your house. If it is drawing well up the chimney that is a good sign.

Welcome to the group and good luck!
 
Flaky dry creosote is good. Hard sticky like hard sap is bad...

I heat my shop 100% with wood... And I check the pipe as weather permits. I do a sweep in late spring, or fall... And then wait for a rainy night, and fire up the stove to burn off any excesses..

My pile after cleaning is usually about 2 inches high.....
 
There is no reason to have it swept after a few short weeks. The hardest part of that job is removing the baffle. Can the roof be accessed? If so, just do it yourself.
 
Creosote is generally described in three stages. Stage one is usually described as the powdery black soot and sometimes the early stage two. Stage two gets into the shiny dry, crinkly crunchy deposits and stage three is a drippy, sticky glaze.

Your pic looks like maybe an early stage two crunchy stuff. If that picture was just what fell down on its own and came from six weeks of burning, I think I'd take a closer look at how much is actually built up in the liner.

And +1 one on trying the SootEater if you have the access to use one.
 
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Thank you for the input so far.

I was planning on buying a brush and sweep it myself, but I was going to have the pro do it the first time so I could watch him and see what the results looked like. I guess i could just go ahead and get the brush and do it.

That rotary system looks interesting. It looks like it would do a better job than just a brush. Although I ould think it would be messy to do it from the bottom up and have the insert door open while doing the cleaning. I was just going to keep the insert door closed and get up on the roof and do it top down. Any tricks for cutting down on the mess if you do it from the bottom up?

Thanks.
 
If you have easy access to the roof, top down is probably the way to go. I just remove my baffle and use the sooteater from the top and let the soot accumulate on the floor of the stove. Easy and clean.
 
Although I ould think it would be messy to do it from the bottom up and have the insert door open while doing the cleaning

I clean mine bottom up and its fairly simple to keep clean. Simply get a sheet of plastic and tape it over the door and either leave one corner open or to be more thorough poke a small hole in the plastic to run the brush shaft through. The only mess is the one on your hands when you are taking the shaft segments apart. Sure beats a reaching over my head on a two story roof.
 
I bought the SootEater and will report back after the first cleaning. Actually, I bought 2 of them because it was cheaper than buying 1 plus the additional rods I need for my 25' flue. At least I will have extra rods and a backup cleaning tool.
 
I bought the SootEater and will report back after the first cleaning. Actually, I bought 2 of them because it was cheaper than buying 1 plus the additional rods I need for my 25' flue. At least I will have extra rods and a backup cleaning tool.

Sweet! If your results are as others here as mentioned over the years, you should do well.

Are you going to be cleaning from the top down or the bottom up?

If you go from the bottom up, just be careful when those weed-wacker-ish strings get up in the cap.

Keep us posted

pen
 
I see your from se mass..... Where abouts? I'm in Taunton and have the HI 300 which is practically the same stove just cast.
 
I sweep mine once a year and get about two cups of ash. I wouldn't do it that often if my wife wasn't paranoid of a chimney fire. If you burn hardwood you should get similar results. You'll get plenty of creosote if you burn pine or other conifers and don't sweep.

I had a friend that was helping a nighbor who had a stove that wouldn't draft. He couldn't get th cap off the flue and when he did he was amazed at what he saw. The flue had tremendous creosote buildup with only a 2" or so hole up the middle. The owner had burned pine he harvested off his property and nothing else. He never swept his flue and risked loosing his house. He ended up with a new flue.
 
I sweep mine once a year and get about two cups of ash. I wouldn't do it that often if my wife wasn't paranoid of a chimney fire. If you burn hardwood you should get similar results. You'll get plenty of creosote if you burn pine or other conifers and don't sweep.

I had a friend that was helping a nighbor who had a stove that wouldn't draft. He couldn't get th cap off the flue and when he did he was amazed at what he saw. The flue had tremendous creosote buildup with only a 2" or so hole up the middle. The owner had burned pine he harvested off his property and nothing else. He never swept his flue and risked loosing his house. He ended up with a new flue.

Not to side track this thread but the pine wasn't the cause of his issues, poor burning practices were.(unseasoned wood, running the stove wrong etc) Plenty of of west coast members burn nothing but pine and have no issues.
 
The danger with burning pine is not the wood it's the person running the stove. Pine is high in oils. These oils burn even when the wood is not fully seasoned. That leads some fools to think that they can get away with burning it a month or two after it's been split which is very wrong. It needs to be seasoned just like any other wood. Without seasoning the wood will still burn and the heat will release a lot of steam, cooling down the flue gases. These gases will condense on the inside of the chimney as creosote. Let the unseasoned pine smolder and one can plug up flue in no time. Burn dry pine in a modern EPA stove at a reasonable flue temp and the flue will stay clean.
 
Unseasoned hardwood will give you creosote in your chimney fairly quickly, as will unseasoned pine. Season either and you shouldn't have any problem. I run into the pine myth a lot here in the east, I only know one other person who is not afraid to put it in their stove.
 
I had always been a believer in the pine myth...until I started reading these forums and found out the truth. I never burned pine before, but now I have some very dry pine (11%) than I burn to get fires going fast. I'll also burn it if I will be sitting there watching a sports game or whatever and I don't mind feeding the wood into the stove often. It saves my hardwood for when I need longer burn times. I'm still building up my wood supply.
 
I like our pine and fir splits to be thick. This requires some additional seasoning, but it helps extend the burn time when burning conifers.
 
Looks like i stand corrected.

I use a piece of pine to get the fire started in the morning but that's it. I will say that the Monterey pine I cut sometimes has lots of sap - dried sap in clumps inside and out. I would think if it was burned it would leave deposits in the flue. I had friends that burn the same species of pine and sweep once a month in the winter.

Anyone else burn a lot of seasoned, sappy pine? What are the results.
 
The creosote is not coming from the pitch, which burns like oil or wax, it comes from condensation of the unburnt wood gases on the interior of the flue pipe. If the stove is a clean burner it is going to minimize the amount of unburnt gases going up the flue. If the wood is properly seasoned, the fire is not smoldering (ie: no visible smoke) and the flue temp at top is 250F or hotter, there shouldn't be any excess accumulation in the pipe.

That said, these oils can get really saturated at the base of some pine trees. This is what fatwood is made out of. If the tree is very oily at the base, split that bottom layer up for kindling and fire starters.
 
The creosote is not coming from the pitch, which burns like oil or wax, it comes from condensation of the unburnt wood gases on the interior of the flue pipe. If the stove is a clean burner it is going to minimize the amount of unburnt gases going up the flue. If the wood is properly seasoned, the fire is not smoldering (ie: no visible smoke) and the flue temp at top is 250F or hotter, there shouldn't be any excess accumulation in the pipe.


Thanks for the explaination. I burned wood for years but never knew why creosote built up.
 
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This is why we recommend an internal flue temp to be around 400F+. That's a rough number, it depends on a lot of factors like interior vs exterior chimney, single vs double-wall connector, length of the flue system, outside temps, etc..
 
OK, here's my update....

As you guys recommended, I bought the Gardus Soot Eater:

http://gardusinc.com/sooteater.html

I used it to clean my flue liner from the top down. I just left the door to the insert shut to contain the soot and dust. The flue for my insert is 25' long, and it is a 6" round stainless steel liner. The whole set up was installed at the end of last winter. I burned about 6 weeks last year and 2 weeks this year - so about 2 months total.

On initial inspection from the top of the chimney, the flue liner was coated with about 1/8" of black powder. I did not see any signs of glaze at either the top or the bottom end of the liner.

I used the Soot Eater on the top few feet of the liner and took this picture:

liner.jpg


After cleaning the entire liner, I ended up with this pile of soot in my insert. It was about 1/2 of a coffee can of soot:

soot.jpg


Looking up at the flue it now looks like this:

liner-bottom.jpg



I'd say it looks good to go now.

The interesting thing is that I think the vast majority of this soot has come from the last 2 weeks of burning and not from the 6 weeks last winter. Last winter I only burned dry oak. This year because it is the shoulder season, I tried burning dry (11%) pine slabs from a local saw mill. The slabs were all cut to stove size and I figured since it was so dry it would be nice wood to get a quick hot fire going. The problem is that half of the wood is bark and it creates a ton of ash in the fire box. If you look at the top of this thread you will see the small pile of soot on the top of the fire bricks from the top of the insert. When I took those bricks down 2 weeks later, they were covered in black soot. I couldn't believe the difference. The only difference between last year and this year is the pine slabs. I don't think it is the fact that it is pine vs. oak (since the pine is 11% MC) but the fact that there is so much bark on it. What do you guys think?
 
Not sure about the bark, but I think many people get more creosote in shoulder seasons because they're not burning the fire as hot. Based on the pictures I'd say you're good to go as well!
 
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