My Chimney Extension Experiement --Begreen suggestion

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Woodcutter Tom

Feeling the Heat
Apr 28, 2019
334
Northern Illinois
My Chimney Extension experiment

Begreen had suggested that I try temporarily extending my chimney to see if that helped with my draft. I used two sections of stove pipe stuck in my chimney pipe.

My Stove: Pleasant Hearth WS 2417

My Chimney Height: 13 feet above stove top. (5 feet of stove pipe; 8 feet of Selkirk 6 inch diameter chimney; Deluxe rain cap.

--Removed rain cap and stuck 48 inches of stove pipe into end of chimney.--


My Wood: Walnut 15.5%
Hickory 17.3%

Wood was brought inside house; left overnight; split; Used SBI moisture meter.

(Wood that was split, then left overnight inside registered about 2% dryer than above readings.)


I recently did the dollar bill test. The bill would not slide anywhere along the door edge.

The digital reading is a PID connected to a thermo coupler attached to my stove pipe about 4 inches above the stovetop.
The Rutland is centered on top of the stove.

I used an IR device to double check my temperature readings. The IR device backs up the readings.

I took pictures every ten minutes after I got the stove up to heat and had shut down the primary air vent. The pictures show the results.

I did the same thing earlier in the day without the extension. Results were pretty much the same. Lose flames and then heat after about ½ hour.

I have never hit 400 degrees on the stove top.

1:08 pm Primary air fully shut down
 

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Pic set 2. 1:20 pm
 

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Pic set #3. 1:30 pm.
 

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Pic set #4. 1:40 pm

At 1:46 there were no flames in the fire box.
 

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Pic Set #5. 1:50 pm
 

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After the 1:50 pictures I opened the primary air intake. At 2:00pm the coals looked like this:
 

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At 2:07 I broken down the coals to display what was left of the wood.
I am not sure the extension did anything at all. Maybe got the wood burning quicker, but definitely not longer or hotter.

I did the same experiment in the morning without the extension. The same results were just about the same. 1/2 hour from 'good burn going' to 'just hot coals'.

Any thoughts , Ideas, Comments, Questions??

Thanks.
 

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Well done on the documentation. It's a small firebox and it was not filled to capacity, so the short burn time is not too surprising. What is surprising is that the stove top didn't get hotter.
 
Try leaving primary air open or half open for a while? Fully shut down on my stove would kill the flame immediately and you won't get a hot burn at all.
 
Perhaps put a complete load in north/south. Shorten up a load of splits if necessary. Significantly short of a complete load by the looks of it. Easy experiment. That sucker should roast if it's got good fuel and all the air it needs? As mentioned you may be shutting down the primary air to much. And to soon? Lots of coals like that would make me consider running more air during the cycle. Couple ideas!
 
Thanks for the replies guys. I appreciate it.

My main goal is to get more heat out of the stove. After all that is what the thing is for. As I stated, I have never had this stove over 400 degrees. I had read in another post (and may have misinterpreted it) that shutting down the primary intake would increase the secondary burn causing the heat to skyrocket. I might have taken that to the extreme as I worked the primary intake until it was totally shut. I thought with the extension that I would get more draft, pulling the air thru the secondaries.

I ran it last night with the primary shut about 1/2 way and got longer burn times. (extension removed)

Last weekend I cleaned the stove pipe, chimney pipe and the area inside the stove above the top firebricks. I get a small amount of particles spread across the top side of the fire bricks. I was satisfied with the amount of creosote in the pipes. I have been running the stove since late October. I start with top down fires, trying to get to flames and heat quickly.

I will continue to work with log size, amount, placement, and air adjustment in search of heat.
 
I can pretty much never shut my primary air all the way. Have to leave it like 1/8-1/4” open or stove does not perform well


Sent from my iPhone using Tapatalk
 
I can pretty much never shut my primary air all the way. Have to leave it like 1/8-1/4” open or stove does not perform well


Sent from my iPhone using Tapatalk
I think this really depends on the stove and installation. If I don't completely shut my air control early enough, the stove will burn too hot with a full load. Once my STT hits about 400 my air control is closed.
 
My main goal is to get more heat out of the stove. After all that is what the thing is for. As I stated, I have never had this stove over 400 degrees. I had read in another post (and may have misinterpreted it) that shutting down the primary intake would increase the secondary burn causing the heat to skyrocket. I might have taken that to the extreme as I worked the primary intake until it was totally shut. I thought with the extension that I would get more draft, pulling the air thru the secondaries.
The point of the extension was to improve secondary combustion. With a short chimney you might not be able to turn down the air all the way with this stove.
 
I still think you will better off with more chimney, especially with outdoor temps in the 40s, but here is another experiment. This will be lighting the fire from the bottom up. Take a few 10" long, 2x4 cut-offs and split them in half. Place 4 of the now 2x2x10" pieces and put them on the firebox floor, about 4" apart, laid parallel to the stove sides (N/S). Ball up a few pages of newspaper and place them in the middle of the stove. Then place the remaining 2x2 pieces across the bottom "sleepers" and put splits on top of them to an inch below the tubes. Light the paper and leave the door open an inch until the fire gets going. Close the door but keep the air control wide open until the fire is burning well. Then close down the air about halfway and let it burn. If the fire is raging turn the air down to 25%, but no more, otherwise leave the air at around 50%.
 
Tom you and I have the same stove. Every bad review I have read about this stove has been linked to one (or both) of two issues - MC and flue height. I have 28' of insulated stainless liner above my stove and even burning less than ideal wood my stove cranks heat to the point of nearly driving us out of the room. Sometimes I turn on the circulation fan on my furnace to move heat out of the room the stove is in.

On reload I have wicked flames of hell for several hours followed by glowing logs and secondary burn blue pop-up thunderstorms for another hour to hour and a half. The days where temperatures have been in the single digits here we burned hard and fast - a typical burn cycle was 5-6 hours. Stove top temperatures during burning flames are in excess of 600 degrees. During the blue pop-up thunderstorms of flames stove top temperatures are above 400 degrees on the isolated times I have measured out of curiosity.

I load the stove as full as I can get it on a bed of coals, keep the door pushed up (not latched), primary damper wide open, and it takes less than 10 minutes for the stove to reach 500 degrees. I close the door when the stove top temperatures reach 500 degrees, I close the primary damper once it hits 600 degrees and let it do it's thing. As far as a cold start I load the bottom layer with thick splits, then a layer of thinner splits, and top it with all the kindling gathered from wood splitting. I stuff wadded paper on top, along the sides, and in any openings I can find in the charge of wood. With the primary damper wide open I light the top, have the door pushed up (not latched), and latch it once the stove top registers at 500 degrees. Once it hits 600 degrees I close the primary damper.

I am not sure why your stove is struggling reach useful temperatures but I would like to make a suggestion if I may. Repeat your test using at least three pieces of wood rather than two and do it on a hot reload as opposed to a cold start up. An old-timer once told me that it takes three pieces of wood on fire to produce usable heat and to maintain a good burn - I am not sure if that is true or not but certainly worth a try. On a cold start up I consider my first load to be more of a "priming of the well" so to speak as it gets the firebox and flue to operating temperature. My theory is that the flue is the engine that drives the stove. I have found with this stove it takes a full load to make it run halfway decent.

At any rate - those are my two coppers for whatever they may or may not be worth.
 
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I still think you will better off with more chimney, especially with outdoor temps in the 40s, but here is another experiment. This will be lighting the fire from the bottom up. Take a few 10" long, 2x4 cut-offs and split them in half. Place 4 of the now 2x2x10" pieces and put them on the firebox floor, about 4" apart, laid parallel to the stove sides (N/S). Ball up a few pages of newspaper and place them in the middle of the stove. Then place the remaining 2x2 pieces across the bottom "sleepers" and put splits on top of them to an inch below the tubes. Light the paper and leave the door open an inch until the fire gets going. Close the door but keep the air control wide open until the fire is burning well. Then close down the air about halfway and let it burn. If the fire is raging turn the air down to 25%, but no more, otherwise leave the air at around 50%.
I'll give this a try today. I let it burn out yesterday, so that I could totally clean the inside today. I planned to look around inside just to make sure nothing is blocked (air tubes) and then experiment. My fire box is 10 1/2" deep by 18" wide. If you see this before I start, should the east- west 2 x 2s be longer than the 10" ones (to reach the sides of the firebox)?
FYI: temp right now (7:45am) is 27 degrees. We might hit 40 today. Yesterday we hit 40, but next 6 day highs are predicted to be 25 - 30 degrees.