What should inside my connector pipe look like?

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.

bcarp

Member
Jan 19, 2021
39
BC Interior
Hello,

I’m relatively new to wood burning and have been burning a new PE Summit LE for the past 14 days. I follow begreen’s top down fire starting/burning method and use dry pine/spruce wood. I have excel unltrablack double wall connector with a t-clean out as a 90, then about 24” hoziontal into a clay lines brick chimney. I have a probe thermo about 20” above the stove top.

I keep the probe temps in the 4-600 range during the day and get it up to 600f Then Close the air down about 85-90% burn overnight. Usually wake up to half a firebox of coals, open up the air and throw a few logs on and get it up to temp again.

I thought I’d take a look inside my connector pipe tonight and this is what I saw, attached pics. 1 pic looking down into stove - you can see the probe, the other is looking toward the brick chimney.

Does this look normal? I’m curious if this is more creosote than would be expected?

thanks for your help.

7ADEE1C5-5AC5-44F4-9624-43F084D825F1.jpeg F4D83C61-2D5D-438C-9407-B17F0FBF3649.jpeg B09C6925-2889-4C69-8320-742CC6405AB1.jpeg
 
That looks excessive to me especially for only 2 weeks, buy I do not have any experience burning pine or spruce. Does your clay tile chimney have a stainless steel liner in it?
 
That looks excessive to me especially for only 2 weeks, buy I do not have any experience burning pine or spruce. Does your clay tile chimney have a stainless steel liner in it?

no it’s a 6x10 clay liner, no s/s insert.
 
no it’s a 6x10 clay liner, no s/s insert.
I would imagine it probably is not drafting properly with that set up. You really need an insulated SS liner the stove will operate better and its much safer. I would imagine the clay tile has a larger build up of creosote as well. here is what happens to clay tile in a chimney fire
 
Ok, haven’t noticed any draft issues. Fires start easy and no smoke back into the house. I’ll sweep the chimney tomorrow and see what’s there.
 
The cross sectional area of you flue is over double that stove calls for a 6" flue. The cross sectional area for that is 28.27 and the area for a 6x10 is 60 inches squared.
 
I agree with everything above. You may have to open it up more on your overnight burn for the wood you are burning to get complete combustion. My Voglezang Ponderosa does the same thing if I try to get too long a burn. Wood type and dryness and weather all impact my burns overnight also. I use a damper in the stack also.
 
I agree with everything above. You may have to open it up more on your overnight burn for the wood you are burning to get complete combustion. My Voglezang Ponderosa does the same thing if I try to get too long a burn. Wood type and dryness and weather all impact my burns overnight also. I use a damper in the stack also.
When I open it up too much more for an overnight burn I get flue temps creeping over 600 quite easily.

one thing I have been thinking about is the size of the wood I’ve been using. I have been putting in some larger 10” or so splits and the odd 6-8” round for overnight, maybe I should stick to smaller pieces and make sure there’s more gaps between the pieces?
 
600 deg flue temps are not bad, ideally you want a 575 - 650 deg stove top for clean operation, what I think is happening here is that 90deg bend in creating turbulence and that swirl is helping to aid in depositing extra creosote in the pipe area.
 
  • Like
Reactions: bcarp
600 deg flue temps are not bad, ideally you want a 575 - 650 deg stove top for clean operation, what I think is happening here is that 90deg bend in creating turbulence and that swirl is helping to aid in depositing extra creosote in the pipe area.

KennyP2339- what do you recommend instead? This is what the stove dealer sold me, I questioned why not an elbow and he said he doesn’t even sell them, just sells/installs the t as they have a clean out for inspection/cleaning. He assured me I shouldn't be seeing creosote as a result...
 
Is there any upward slope in the horizontal run?
 
Is there any upward slope in the horizontal run?
There is some Upward slope on the horizontal as it goes through the brick wall into the chimney, but all of the stove connector pipe is level as it had to be with the T-90.
 
The other brand of probe meter identifies the “normal” range of flue temperatures as 400-900. Even my ultra efficient blaze king puts out 400 degree (verified with thermocouple) flue temperatures on low when burning our softwoods.

You’re running your stove too cold. Creosote is the result, and that’s too much for two weeks.

At least get your flue temperatures up to the middle of the range, 650, and check the pipe again.
 
  • Like
Reactions: PA Mountain Man
The other brand of probe meter identifies the “normal” range of flue temperatures as 400-900. Even my ultra efficient blaze king puts out 400 degree (verified with thermocouple) flue temperatures on low when burning our softwoods.

You’re running your stove too cold. Creosote is the result, and that’s too much for two weeks.

At least get your flue temperatures up to the middle of the range, 650, and check the pipe again.
Ok interesting. Stove dealer told me not to run this thing over 600f on the probe thermometer.

I’ll clean it all today and start running it hotter and see what comes of it.
 
Ok interesting. Stove dealer told me not to run this thing over 600f on the probe thermometer.

I’ll clean it all today and start running it hotter and see what comes of it.

Sounds like a misunderstanding. He probably meant not to run the stove over 600. Even that is awfully conservative but closer to appropriate for the stove.
 
Yeah maybe, although he insisted I only needed a probe and stove top temps were useless...???
 
I cleaned the chimney, there was about 1 cup of flaky creosote about 15’ up, nothing below that.

Hopefully running hotter does the trick to keep the connector pipe cleaner.
 
Yeah maybe, although he insisted I only needed a probe and stove top temps were useless...???
IMHO it's nice to have both, every stove install has a unique personality and having some thermometers helps you figure out what's going on. They give you the feedback to make appropriate adjustments. You should be able to safely run hotter than 600. I like to get up to 700+ after a reload, and then work my way down to 400 and cruise there. That ensures I have a good clean burn going and I've "dried" off any residual moisture from the firewood on the reload.
 
  • Like
Reactions: bcarp
IMHO it's nice to have both, every stove install has a unique personality and having some thermometers helps you figure out what's going on. They give you the feedback to make appropriate adjustments. You should be able to safely run hotter than 600. I like to get up to 700+ after a reload, and then work my way down to 400 and cruise there. That ensures I have a good clean burn going and I've "dried" off any residual moisture from the firewood on the reload.
I should clarify I'm taking about flue probe temps. At least your deposits are the fluffy kind.
 
  • Like
Reactions: bcarp
I should clarify I'm taking about flue probe temps. At least your deposits are the fluffy kind.

That’s what I was thinking, thanks for clarification.

when it comes to STT, what is a reliable thermometer and where is the best location to take the readings?