Help with condensate/creosote problem

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JayBuck603

New Member
Nov 17, 2012
2
Hello to everyone, I have been snooping around the forums and finding a lot of great info so I decided to join and see if someone can possibly help me out. My predicament is as follows.

About a week ago I picked up and installed an old fisher baby bear into my fire place.
I went with the fisher because I am cramped for space as you can see in the pics and I wanted to be able to use normal log lengths (I also got a good deal on it re-finished). My house was an old camp the original owner converted to year round and he did everything himself so I have been going through and trying to right everything he did wrong. The fire place was originally cinder block and poured concrete which I had re-faced in cultured stone. The chimney is outside of the house and is also made of pured concrete but it has a clay liner which is in good condition.

A couple days in all is well and the house is nice and warm and I'm learning how to run the stove pretty well. I decide to go have a peak at the chimney cap and you can see in the pics what I find. It appears as though creosote was dripping off of the cap and on to the chimney. Some of the drips were sticky but some were just water and soot. I havent run the stove since I noticed this. I have kept the stove pipe temps right around 400 degrees and the stove top temps around 550 to 600 degrees. I am burning well seasoned red oak as well as some very dry silver birch.

What I figured was going on is since my cement chimney is outside the house and the outside temp is around 30 degrees the chimney is too cold and I am condensing a lot of the smoke forming the creosote like drips. I have been told installing an insulated liner will take care of the problem as it will help maintain higher flu temps. Any help would be greatly appreciated since I am listening to my furnace run as we speak. I have included some pics to help diagnose, some of the photos show some black splatter on the inside of the fireplace that came out of a spot where the stove pipe enters the flu.
 

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Welcome to the forum!!!

That seems to be a significant amount of creosote that has dripped down. Are you certain your wood is seasoned? From what everyone says, OAK should be cut/split and stacked for at least 3 years before being burned.

The Clay liner seems to be in pretty good condition.

My concern is as follows: If it is condensing now it will only condense more later in the colder months. Where do you live? I would certainly install an insulated liner. The stack doesn't seem too long and it should be a fairly easy job.

On another note, I am certain there must be some stoves that can fit into that opening that are EPA compliant...I am certain others will chime in and provide better advice!

Again, welcome to the forum!

Andrew
 
I think your diagnosis is pretty much right on. The smoke is condensing on your chimney walls. An aggravation is the older stove not burning as clean as a newer one. It looks like its in great shape though!

I think the main issue is your chimney. It looks like it may be a bit short so draft is probably not what it could be. This coupled with the large tiles allow the smoke to travel slowly up the chimney and it has more time to condense. Lining it would probably make a world of difference.

One other thing I noticed is that your stove goes almost up to the end of the old hearth. Do you have something in front of it that reaches 18" in front of the stove? Sparks will eventually pop and fly out that far and beyond.

Matt
 
A couple days in all is well and the house is nice and warm and I'm learning how to run the stove pretty well. I decide to go have a peak at the chimney cap and you can see in the pics what I find. It appears as though creosote was dripping off of the cap and on to the chimney. Some of the drips were sticky but some were just water and soot. I havent run the stove since I noticed this. I have kept the stove pipe temps right around 400 degrees and the stove top temps around 550 to 600 degrees. I am burning well seasoned red oak as well as some very dry silver birch.

What I figured was going on is since my cement chimney is outside the house and the outside temp is around 30 degrees the chimney is too cold and I am condensing a lot of the smoke forming the creosote like drips. I have been told installing an insulated liner will take care of the problem as it will help maintain higher flu temps. Any help would be greatly appreciated since I am listening to my furnace run as we speak. I have included some pics to help diagnose, some of the photos show some black splatter on the inside of the fireplace that came out of a spot where the stove pipe enters the flu.

Welcome to the forum Jay. Glad to have you.

The number one flag that was raised to me was that comment about the "well seasoned red oak." Had you described what that meant you probably would have nailed the biggest factor of your problem. I also noticed that you called the oak well seasoned but the birch was very dry. Why the difference?

I'll state right away that to be well seasoned, red oak needs lot of time after splitting the wood. Once it gets split, stack it in the windiest spot on the place. If that is in sunshine, so much the better but wind is the most important for drying wood. Then once it is stacked, off the ground in single rows, oak needs 3 years in the stack before burning. Some, in certain climates can get by in 2 years but even then if they left it one more year it would be super firewood.

Then, of course, the second factor is the chimney as Matt has stated. That type of chimney is not the very best and then being short compounds the problem. Still, I know of many who have burned well in these situations as long as their wood was really dry. Also, you really need to put a cap on that chimney.
 
+1 To what Dennis said.
 
How big is that flue? It looks like a rectanlge 8x6.

Like others have said you're wood isn't dry enough for one, but decreasing the size of the flue with an insulated liner will help heat up the chimney and hopefully push everything out.

I would leave the cap off as well.
 
Usually its the fuel. Most think well seasoned wood was split last month. If its oak, is needs to dry for two years. Thats split and stacked off the ground in single rows. Its a lot of work to have efficient fuel. Other hardwoods usually only require 12 mos. What happens is the moisture eventually does come out of the wood as its slowly climbing the walls of your cold chimney.
 
Damn dude...

Was the upper surface of the chimney clean before you started burning, or is that years' worth of accumulation from the former user? If it's definitely from your burning, I note that your chimney interior appears to be relatively clean, which implies that you're running at good temperatures. If you were choking off the air intake too soon or otherwise doing something to stifle the burn, you'd get more smoke, but you probably wouldn't be running at those temperatures.

Describe the firewood you're burning... is the bark still on it? Are the ends cracked? How long has it been down/split? Where did it season (in a pile under a tarp, stacked with no cover, etc.)

Also, how are you starting the fire? If it takes a long time to get up to speed, that initial smouldering burn could be throwing more soot than normal up the chimney.
 
Had the same nasty look on the top of my chimney last season.
Wood has had 1 more year of drying and poof, problem gone.
It's your fuel my friend.
 
Wow I should have checked for replies sooner! Thanks for all the input. I installed a 5" liner with clean out tee last week and it seems to have helped a lot. Since everyone keeps saying its my fuel the wood I'm burning is red oak that has been split and stacked in a very windy spot in the sun for a year. The wood has plenty of cracks or "checking" in the ends and has 21 to 23 percent moisture with the meter. I think my problem was the chimney combined with the less efficient stove. I've been looking into installing a baffle to help with the smoke. Again I thank every one for the input and advice.
 
If you search around the site, there is a poor mans modfication to Fisher Stove to make them burner a bit more effciciently and cleaner
 
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