Single wall pipe and creosote. (Update)

[toddh]

This is my first year burning. I have had a problem lately with getting the temps up on the stove. I pulled my pipe last night and I have creosote and 1/4" in it. I am not sure about the chimney yet as I have not checked it. What causes creosote in the flue? Is it getting too cold? Bad wood? Should I run double wall pipe instead?

I got up on the roof this morning. The chimney looks perfect! I have a 6 1/2 x 11 ID clay liner. So I just have creosote in my 6' of single wall pipe out of the stove.

 

[Jags]

Too cold - the smoke is sticking to the pipe instead of going out. Now the big question is - why is it too cold. Wood not seasoned properly? Operation of the stove?

Check that stack completely. A 1/4" layer of gooey stuff has a very high fuel content. If that lights off - your gonna get seriously excited.

More 'splain'in please... (as in run temps, what are you using for fuel, etc.)

 

[toddh]

I am not sure about my wood. It was cut 1 1/2 years ago and split this fall. I run the stove in the 500 F range. Usually run it in cycles. Reload at 300 F although in the morning and when I get home from work it is down to 200 F.

 

[Jags]

and split this fall.

Huston - we have a problem. When you say this fall, do you mean Sept-Nov of THIS year? Cuz if so - you got a fuel problem. I would bet that you are trying to burn wood with a moisture content North of 25% and probably above 30%. That is too high. If you have no other options for fuel - you will need to go into disaster recovery mode.

Split wood smaller.
Run hot fires - 550-650F would not be unreasonable for most stove.
Supplement fuel with known dry(er) stuff, such as pallets or bio-bricks
INSPECT AND SWEEP FREQUENTLY. On a monthly basis would not be out of the question.

 

[toddh]

I've ordered a meter and have started to cut wood for next year. I am anxious to see what the MC is at this point. Yes it was split in October of 2010.

 

[Jags]

Yes it was split in October of 2010.

Confirmed - Myth Busters.

 

[toddh]

Another question? If I am running the stove at 500-600F and I am still getting creosote in my pipe then wet wood causes this? and not temps as they are on target?

 

[Jags]

Another question? If I am running the stove at 500-600F and I am still getting creosote in my pipe then wet wood causes this? and not temps as they are on target?

That would be a pretty safe bet or assumption. Also keep in mind that stove temp and stack temp are two different critters. On a single wall stove pipe, you should see and maintain a surface temp of 200-400F (that translates into an internal temp of ~ 400-800F) if you are dealing with wet wood. But don't go doing ANY of this till you have that stack inspected and cleaned as needed. By reaching those higher (safer) temps, you stand a chance of igniting what is already stuck on the sides of the pipe. That would be bad.

 

[toddh]

OK. I will clean and inspect. Last question, if I have good wood next time and I am still having issues do I need to go to a double wall pipe?

 

[Jags]

OK. I will clean and inspect. Last question, if I have good wood next time and I am still having issues do I need to go to a double wall pipe?

I can't pin that answer down. There are many that use a single wall pipe with good results. If you have known good wood and are still having a creosote problem, we should probably re-evaluate your whole operational procedure.

 

[oldspark]

OK. I will clean and inspect. Last question, if I have good wood next time and I am still having issues do I need to go to a double wall pipe?

How much stove pipe do you have before you get to the chimney?
Get a flue temp sensor also.

 

[toddh]

I have maybe 6 feet to the thimble in the wall.

 

[blades]

Wood sitting in the round even for 1.5 years likely will not be seasoned properly, ie less than 20% moisture content, this being somewhat dependent on the type of wood and atmospheric conditions. Generally 1-2 years for split wood is what is needed. Oak, Hickory and similar dense hardwoods will take in excess of 2 years split in my neck of woods to get down to 20%. So chances are that your fuel is not optimum. You have not given much info on the flue system other than the single wall pipe. If your flue consists entirely of single wall, exposed to the external temps, it will not be possible to maintain high enough temps to prevent condensation of creosote in the flue assembly.

 

[Jags]

I have maybe 6 feet to the thimble in the wall.

With all things working right, you should have no issues with 6ft of single wall.

 

[toddh]

Wood sitting in the round even for 1.5 years likely will not be seasoned properly, ie less than 20% moisture content, this being somewhat dependent on the type of wood and atmospheric conditions. Generally 1-2 years for split wood is what is needed. Oak, Hickory and similar dense hardwoods will take in excess of 2 years split in my neck of woods to get down to 20%. So chances are that your fuel is not optimum. You have not given much info on the flue system other than the single wall pipe. If your flue consists entirely of single wall, exposed to the external temps, it will not be possible to maintain high enough temps to prevent condensation of creosote in the flue assembly.

I have 6 feet of single wall going to a clay thimble thru the wall and up a 25 foot clay liner masonry chimney. Outside wall.

 

[Jags]

I have 6 feet of single wall going to a clay thimble thru the wall and up a 25 foot clay liner masonry chimney. Outside wall.

I don't like the sounds of that. No liner in the chimney? This is gonna be a trouble spot for sure.

That stove should have a 6" pipe from stove to sun light. On an external chimney, I would even HIGHLY recommend that it be insulated the whole length of the chimney. Trying to keep that much masonry up to temps to avoid creosote is going to be futile.

 

[brianbeech]

I have 6 feet of single wall going to a clay thimble thru the wall and up a 25 foot clay liner masonry chimney. Outside wall.

I don't like the sounds of that. No liner in the chimney? This is gonna be a trouble spot for sure.

That stove should have a 6" pipe from stove to sun light. On an external chimney, I would even HIGHLY recommend that it be insulated the whole length of the chimney. Trying to keep that much masonry up to temps to avoid creosote is going to be futile.

Oh no! Don't tell me that! I'm getting my stove installed tomorrow with 6' of pipe to an 8"x8" clay lined masonry chimney going through the center of the house (only last 6 feet is exposed to weather). Flue is roughly 26' high. Should I be looking forward to a problem too?

 

[toddh]

Inside the house chimney is much warmer than an outside chimney. You should be fine. Mine drafts fine. I just need better wood.

 

[EatenByLimestone]

One problem at a time. You might find the chimney to not be much of an issue after you get your wood in better shape.

One question though. How much of that 6 feet is horizontal?

Matt

 

[Battenkiller]

I have 6 feet of single wall going to a clay thimble thru the wall and up a 25 foot clay liner masonry chimney. Outside wall.

Ah-ha!

Even though the stove may take off and burn well because the gases themselves are hot enough, the cold flue liner will cause them to condense on the inside surface. You can have good draft with high flue temps and still get condensation on the inside if the tiles themselves are cold.

You need to run that stove hot for a long time to get the clay liner warmed up and dry up the goo you got on there from the night before. Or takes Jags' advice and invest in a liner - by far the best and safest option. In fact, I wouldn't even run a stove with a chimney like that. Mine's an interior masonry chimney and I have enough problems, even running it hot 24/7 and using good, dry wood.

 

[firefighterjake]

+1 to Jags advice, suggestions and recommendations . . . all of it.

 

[Backwoods Savage]

ToddH, don't feel too badly as this is a very common problem with new wood burners. You can get through this and will be a lot wiser in the end. For sure the number 1 factor is the fuel. Getting next year's wood put up now or at least before Spring is a giant step in the right direction but first you have to get through this year. Definitely cleaning the chimney comes first. Finding some good fuel comes next. Good luck, you have been given some good advice from other posters. Just don't give up. Stay at it and it will be worth it all in the long run.

 

[toddh]

Thanks guys. I am going to clean the chimney and pipe. Cut and split wood now for next year and look at possibly lining the chimney depending on what I see this weekend.

 

[oldspark]

I have 6 feet of single wall going to a clay thimble thru the wall and up a 25 foot clay liner masonry chimney. Outside wall.

Ah-ha!

Even though the stove may take off and burn well because the gases themselves are hot enough, the cold flue liner will cause them to condense on the inside surface. You can have good draft with high flue temps and still get condensation on the inside if the tiles themselves are cold.

You need to run that stove hot for a long time to get the clay liner warmed up and dry up the goo you got on there from the night before. Or takes Jags' advice and invest in a liner - by far the best and safest option. In fact, I wouldn't even run a stove with a chimney like that. Mine's an interior masonry chimney and I have enough problems, even running it hot 24/7 and using good, dry wood.

You have problems with your chimney forming creosote BK, how often do you clean it, I guess I need to get up on the roof and look at mine again.

 

[blades]

If the ugly black stuff is real sticky get some of the Rutland creosote remover powder to help transform it to a more removable deposit.