Primary Air Igniting Gasses....this happen to you?

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Sailrmike

Feeling the Heat
Sep 20, 2017
289
06371
What is a c-cast panel? I never heard of that term. My stove appears to just have the 5/16" stovetop....but one of the diagrams in the manual shows a dark line attached to the underside of the stovetop. That could be it. I'll have to look closer when the tubes and baffle board can be removed.


After I got this stove, I started to split my wood into larger pieces. I have oak, ash and hickory. That won't be seasoned for some time yet. Next years wood is already split....into the smaller pieces. I am going to try to kiln dry some of the larger splits in an attempt to have them ready for next year.


I believe that I have good draft. I have an OAK. It is a 5" diameter tube that SBI calls for in their specs. I can feel (and hear) the air entering the end of the tube. My primary air control is very sensitive. Small increments effect the flame in the firebox. I can see the movement of the flames when making adjustments to the primary air control --- The air rushing in and pushing the flames around. That makes me believe that I have good draft. Plus I have tried every combination of chimney height that I can.
If I want, I can create a massive inferno in the firebox. But the heat seems to go out the flue. My highest flue temp was over 1200F when I used some pressed sawdust blocks. I used 5 with a couple of stringers underneath them. The blocks took a while to get going, but when the stringers ignited the blocks soon followed. Big inferno. But the heat did not transfer into the stove top. It went up and out the flue.
It puzzles me that you have STT greater than or equal to the flue temp. I also see that in @begreen's fire staring tutorial where his stove is cruising at 613F Flue and 625F SST.

I am hoping to hear back from SBI soon. I replied earlier this week to some questions they ask me. Hopefully thay can shed some light o this. (but I'll settle for heat, not light)
It looks like your model doesn’t have the c-cast panel. It's not listed in my owner's manual, but it's on Drolet's site for parts:
Screenshot_20210319-103651_Chrome.jpg
I think they added it to protect the stovetop from flames
 

Todd

Minister of Fire
Nov 19, 2005
9,449
NW Wisconsin
I warm the wood inside - overnight or for a few days; split it and then measure it on the split face. The wood I burn this year is either in my garage or in an enclosed shed. Nothing comes from outside racks.
The diameter of my splits is small. My stove last year was 1.2 cubic foot. I split my wood small for that stove. If you look at Begreen's 'Starting a Fire' thread, you will see he has 10 splits in his 3.0 cubic foot stove on at N-S start up. Look at my attached picture. This is my Escape 1500, a 1.9 cubic foot stove. Typically there are about 30 pieces. Next year I will have the same size splits. The following year I may have some larger pieces that I split in 2020.
I think your splits are too small and tending to out gas all at once. I bet once you have larger splits it will be a more controlled burn with more secondaries. I see this with my Jotul F45 when using the wood I cut for my Jotul 602.
 

Woodcutter Tom

Burning Hunk
Apr 28, 2019
169
Northern Illinois
My test today led me to believe that I need to slow my draft down. Even with my outside air closed off, I had the primary air igniting gasses at the front of the stove.
The good news is that during my test I saw the ‘stove top burner’ flames that I have been looking for and I set a new high for the STT. I got to 595 F.

I adjusted my outside air blast gate and the primary aair control during the first hour as I started my fire. At 1 hour the STT was 515 and the Flue was 910.

With the outside air shut down and the primary air control in the complete shut position, the Flue temp creeped up to 1097 F. At that time the STT was 585, but it crept up t 595 during the next 110 minutes as the flue dropped.

Even with the outside air shut down, there was enough draft to pull air into the fire box thru the pedestal seams and the area around the ash pan door. This was enough to generate strong flames at the front of the stove from the primary air. As the flames burnt the gasses and the fresh air, the glass became dirty toward the bottom of the door.

Therefore I think I need to slow down the draft with a damper in the stove pipe. That way I can adjust the draft by adjusting the damper. Instead of trying to stop the air from being pulled into the firebox, the damper will stop the air from being pulled up the chimney.

Thought from chimney experts???
 

ABMax24

Minister of Fire
Sep 18, 2019
1,216
Grande Prairie, Alberta, Canada
I used 5 with a couple of stringers underneath them. The blocks took a while to get going, but when the stringers ignited the blocks soon followed. Big inferno. But the heat did not transfer into the stove top. It went up and out the flue.
It puzzles me that you have STT greater than or equal to the flue temp. I also see that in @begreen's fire staring tutorial where his stove is cruising at 613F Flue and 625F SST.

The hottest part of my stove top is directly in front of the flue. It is possible for flue temps to be lower, the top acts as a heat exchanger the front is usually the hottest and it cools toward the back, I'm sure the back of my stove is much cooler, and is still cooler than the flue temps.


When it gets this hot do you turn down the primary air?

I operate my stove a lot based on flue temps, I aim for 600-650F flue temps while the stove is heating up, I adjust the primary accordingly to maintain this. Then once the stove is up to temp I target 350-600F while the stove is cruising, depending on how much heat output I need. I never let my flue go beyond 1000F, even at 700F I've got the primary almost shut or fully shut.

If you haven't already tried this method give it a go. I find it can take up to an hour to get full heat from my stove, trying to push this faster eventually hits a point of diminishing returns, where the stove doesn't get hot any faster, and all that results is heating the flue unnecessarily and burning the wood down faster.

For reference here is what my stove operates like on low burn, I have a flue damper install here, but this is to slow the draft from my 36' of chimney height. My damper is modified and more restrictive than most to compensate for my excessive draft.


Here is another video before the flue damper was modified, you can see how much more vigorous the flames are here. Under the right conditions I could see a faint glow on the center of the stove tope in a pitch black room, being the reason the flue damper was made more restrictive.



The only other conclusion I can come to is damp wood. That's really the only time I get flue gasses burning at the air wash.
 
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ABMax24

Minister of Fire
Sep 18, 2019
1,216
Grande Prairie, Alberta, Canada
My test today led me to believe that I need to slow my draft down. Even with my outside air closed off, I had the primary air igniting gasses at the front of the stove.
The good news is that during my test I saw the ‘stove top burner’ flames that I have been looking for and I set a new high for the STT. I got to 595 F.

I adjusted my outside air blast gate and the primary aair control during the first hour as I started my fire. At 1 hour the STT was 515 and the Flue was 910.

With the outside air shut down and the primary air control in the complete shut position, the Flue temp creeped up to 1097 F. At that time the STT was 585, but it crept up t 595 during the next 110 minutes as the flue dropped.

Even with the outside air shut down, there was enough draft to pull air into the fire box thru the pedestal seams and the area around the ash pan door. This was enough to generate strong flames at the front of the stove from the primary air. As the flames burnt the gasses and the fresh air, the glass became dirty toward the bottom of the door.

Therefore I think I need to slow down the draft with a damper in the stove pipe. That way I can adjust the draft by adjusting the damper. Instead of trying to stop the air from being pulled into the firebox, the damper will stop the air from being pulled up the chimney.

Thought from chimney experts???

I'm not a chimney expert, but something here to me doesn't seem right. Are the flue temp readings sustained? Or how are they taken? If its a probe type it can take a while for the gauge to indicate the correct reading. 1000F with the primary shut is down right scary. Or is this flue temp measuring device not accurate for some reason?

Especially considering you are running a 12' chimney.

Can you post a picture of how your baffle is installed, that's the only other thing I can think of, if its somehow not installed correctly and allowing gases straight up the flue without touching the stove top.
 
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Woodcutter Tom

Burning Hunk
Apr 28, 2019
169
Northern Illinois
The hottest part of my stove top is directly in front of the flue. It is possible for flue temps to be lower, the top acts as a heat exchanger the front is usually the hottest and it cools toward the back, I'm sure the back of my stove is much cooler, and is still cooler than the flue temps.


When it gets this hot do you turn down the primary air?

I operate my stove a lot based on flue temps, I aim for 600-650F flue temps while the stove is heating up, I adjust the primary accordingly to maintain this. Then once the stove is up to temp I target 350-600F while the stove is cruising, depending on how much heat output I need. I never let my flue go beyond 1000F, even at 700F I've got the primary almost shut or fully shut.

If you haven't already tried this method give it a go. I find it can take up to an hour to get full heat from my stove, trying to push this faster eventually hits a point of diminishing returns, where the stove doesn't get hot any faster, and all that results is heating the flue unnecessarily and burning the wood down faster.
During start up I have experimented quite a bit. With this test I would shut down the primary in very gradual increments when the flue temp was 750 - 800. I do not make any changes based on the stove top temp. When I change the primary air the flue temp will stall, dip then recover and rise again. I keep closing to keep in this range. Before my 1st hour was up, I had the primary totally closed. That said, on my stove having the primary control lever in the totally closed position does not mean that they primary air is totally shut off. Look at the pictures at the start of this post. Completely shut seems to have a bigger opening than 3/4 shut.
The flue temp slowly rose to the 900 range then rose to the 950 range. It fluctuated a bit there; 956 down to 944 then started back up. Within 10 minutes it went from 956 to 1097. 5 minutes later it was at 1030. 5 minutes later 942. 15 minutes later 835. This is with the primary totally shut and the outside air gate shut. Only air would be what passes into the pedestal base on it's own. I have no control during this period. During the rise in flue temp, there was less volatility on the body of the firebox and but the flames across the front of the glass increased. At the highest flue temp, there was not much burn from the centers of the secondary burn tubes. The ends had some rough flames. The flue temps diminished as the front flames diminished.

I'm not a chimney expert, but something here to me doesn't seem right. Are the flue temp readings sustained? Or how are they taken? If its a probe type it can take a while for the gauge to indicate the correct reading. 1000F with the primary shut is down right scary. Or is this flue temp measuring device not accurate for some reason?
See above. The high temps do not stay for very long. I have a K type probe attached to a PID with digital readout. The reads are basically instantaneous. The probe is 2 inch long so that it reads more toward the center of the flue. 3 weeks ago I replaced the probe as I too was concerned that maybe these reading were not accurate. I made sure I bought a probe that was certified to 800 C. The one I had was to 500 C. The readings seem to be consistent with what the other probe measured.


Can you post a picture of how your baffle is installed, that's the only other thing I can think of, if its somehow not installed correctly and allowing gases straight up the flue without touching the stove top.
I always check the baffle plate. I make sure it is pressed all the way back. I can visually see that it is in the correct position by looking at it compared to my front secondary burn tube. There is not much side to side movement. There is also a bracket that will not allow the baffle plate to be pulled too far forward. But I keep mine pressed to the back.

Is there a way to test how a flue damper would effect this situation? Begreen has mentioned that a piece of stove pipe can be added to the top of the outdoor chimney pipe to simulate adding more chimney pipe. Is there a way to simulate a damper????
 

brenndatomu

Minister of Fire
Aug 21, 2013
6,570
NE Ohio
I think your splits are too small and tending to out gas all at once
This ^ ^ ^
The secondary air is being overwhelmed (rich fuel mixture)
 
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Woodcutter Tom

Burning Hunk
Apr 28, 2019
169
Northern Illinois
I think your splits are too small and tending to out gas all at once. I bet once you have larger splits it will be a more controlled burn with more secondaries. I see this with my Jotul F45 when using the wood I cut for my Jotul 602.
This ^ ^ ^
The secondary air is being overwhelmed (rich fuel mixture)
I'll scrounge through wood piles and see if I can come up with large splits that are seasoned. Probably won't test till Monday.

Thanks for your input. Appreciate it.
 
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Woodcutter Tom

Burning Hunk
Apr 28, 2019
169
Northern Illinois
Larger split test
Wood: walnut 17.5 - 18 .5 % MC
Temp 50 F
Wind S at 5 mph
I went into the test thinking I would try to keep the flue temp under 800 F.

My larger split test did not work as I hoped it would. Attached is a picture of the splits loaded up before starting the fire. 15 minutes after start up the flue was at 700 F. I closed the primary about 1/4 of the way closed. Within one minute the flue was at 800 F. When it got to 870 I shut the primary air to about 60% closed. That was less than 1 minutes after it hit 800. One minute later it was at 770. 2 minutes later it was back up to 800. I shut the primary control all the way closed. For the next 15 minutes it fluctuated around 650. During this 15 minutes the STT rose from 250 to 400. Then the flue rose to the mid 800s where it fluctuated for the 45 minutes. The highest the STT got was 475. The flue temp fell to the mid 650 range where it fluctuated for another 1 1/2 hours.
I did not have a lot of secondary burning from the secondary burn tubes. I never had robust streaming flames from the secondary burn tubes.
But I also never had the secondary flames burning off the air from the primary feed above the glass.
There were times when I could smell smoke outside and there were times when I could see smoke coming out the top of the chimney. These occurred when the flue temp was fluctuating in the 650 -700 range.
The fire did not spread to the entire firebox or even to across the wood on the top of the splits. It created a valley down the center of the firebox from top to bottom. I think this was to due to the three holes flowing fresh air to the bottom of the stack.

After 2 hour 15 minutes I opened the primary air 1/2 way. The flames increased and the flue temp went up 100 degrees in 2 minutes. At that time the SST was 440 -450 and it stayed in that area.

I am going to try this again later in the week. It will be too warm tomorrow, so probably Wednesday. For that test I will spread smaller split across the entire top of my stack.
 

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Sailrmike

Feeling the Heat
Sep 20, 2017
289
06371
Larger split test
Wood: walnut 17.5 - 18 .5 % MC
Temp 50 F
Wind S at 5 mph
I went into the test thinking I would try to keep the flue temp under 800 F.

My larger split test did not work as I hoped it would. Attached is a picture of the splits loaded up before starting the fire. 15 minutes after start up the flue was at 700 F. I closed the primary about 1/4 of the way closed. Within one minute the flue was at 800 F. When it got to 870 I shut the primary air to about 60% closed. That was less than 1 minutes after it hit 800. One minute later it was at 770. 2 minutes later it was back up to 800. I shut the primary control all the way closed. For the next 15 minutes it fluctuated around 650. During this 15 minutes the STT rose from 250 to 400. Then the flue rose to the mid 800s where it fluctuated for the 45 minutes. The highest the STT got was 475. The flue temp fell to the mid 650 range where it fluctuated for another 1 1/2 hours.
I did not have a lot of secondary burning from the secondary burn tubes. I never had robust streaming flames from the secondary burn tubes.
But I also never had the secondary flames burning off the air from the primary feed above the glass.
There were times when I could smell smoke outside and there were times when I could see smoke coming out the top of the chimney. These occurred when the flue temp was fluctuating in the 650 -700 range.
The fire did not spread to the entire firebox or even to across the wood on the top of the splits. It created a valley down the center of the firebox from top to bottom. I think this was to due to the three holes flowing fresh air to the bottom of the stack.

After 2 hour 15 minutes I opened the primary air 1/2 way. The flames increased and the flue temp went up 100 degrees in 2 minutes. At that time the SST was 440 -450 and it stayed in that area.

I am going to try this again later in the week. It will be too warm tomorrow, so probably Wednesday. For that test I will spread smaller split across the entire top of my stack.
I've noticed that my stove performs much differently when cold starting like you've done in this test, vs having a warm stove with coals. The load pictured above is too difficult to start a cold stove with. I would do a load like that on a full coal bed only especially with si many rounds!
 

Woodcutter Tom

Burning Hunk
Apr 28, 2019
169
Northern Illinois
I've noticed that my stove performs much differently when cold starting like you've done in this test, vs having a warm stove with coals. The load pictured above is too difficult to start a cold stove with. I would do a load like that on a full coal bed only especially with si many rounds!
Thanks Mike, Here is a pic of my next test. Less rounds; more splits. I took my biggest round, split it and measured 18.4% MC.
Not quite sure when I will fire it up. I want a colder morning that 45 - 50 degrees out. Might be Thursday or Friday.
Thanks for the input.
 

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Woodcutter Tom

Burning Hunk
Apr 28, 2019
169
Northern Illinois
The results from my 2nd big wood test were not much different. I did not get the stove top heat I am looking for. The wood was stacked as in the picture in above post. 41 degrees with 4 mph wind outside. Mostly walnut with 18.4% MC.

I received a response from SBI. They stated that I am not getting heat from the stove due to my starting method. This is what they wrote:

"Hello Tom,

You seem to have a great understanding of your stove and the majority of its function. A few things to point out. In double wall black pipe the probe thermometer should be 18" above the top of the stove for best accuracy. The secondary air tubes will not shoot out flames from every hole. This is a misconception as these are not the same as a pressurized gas burner tube. The primary air adjuster has a pilot hole for when the primary air is reduced to its lowest setting. This adds more air directly to the coal bed. When the primary air is reduced the airwash function is also reduced. The biggest issue I see is the image of your starting load. You have too much wood in the firebox for a cold start up. The tightly packed firewood will act like a heat shield preventing the firebricks from absorbing the heat from the fire. From a cold start use less wood to generate a smaller more intense fire. This will allow for the bricks to absorb heat quicker. Cold fire start should be enough for 20-60 minutes of burning at most to heat the stove. Then load it up once some heat and coals are generated. Chimney draft itself will also have an effect on performance. If the chimney draft is too strong (over drafting) then heat will be sucked up the chimney before it can be absorbed by the stove. I have included a video by Drolet/SBI on good fire starting practices. "


Here is the link to the SBI good fire starting practices video. The link goes to their website where the video can be downloaded.



I tried with smaller start up fires and then added splits to the hot coals.
On two occasions this weekend, I added 6 pieces of 2" x 2" on hot coals. One set was 14.6% MC ash; the other was 14% MC Hickory. These reloads filled less than 1/3 of the firebox. As I got a good fire going in the fire box, I slowly closed the primary air control. With a very good fire going and the flue temperature around 810 F, I closed the primary air to 3/4 shut. The fire diminished and the flue temperature reduced to about 640 F. This took a couple of minutes. Then the fire started to increase and the flue temperature started to increase. When it reached 710 F, I closed the primary air control completely. Flames had started to appear at the front of the stove by the glass. It is easy to see that these flames are from air coming down in front of the glass. Within 2 -3 minutes, the flames have increased significantly and the flue temp has risen to 890 F. The stove top temp was 410 F. Within a few more minutes the flue temperature has risen to 975 F and the stove top 430 F. This is with the primary air control in the total shut position. During this time, I get more secondary burn from the primary air than from the tubes. The burning from the tubes diminishes as the primary air burns the gasses. I believe that if the gasses were being burned by the air from the tubes that the heat would stay in the firebox longer, increasing the heat I get from the stove. But as the gasses are ignited by the primary air, the heat just goes straight up the chimney. I can actually see the flames ignite as the air flows down over the glass, then turn about and go up and out the stove. Once the ignition of the gasses starts from the primary air, it increases quickly and intensifies. Thus creating more heat and draft up the chimney. It quickly builds upon itself. The highest the stove top ever got was 550 F even with the flue over 970F. After the wood has released all its gasses, the flames from the primary air stop and the flue temperature lowers. Then the stove top temperature also lowers.

I have asked SBI to tell me what STT I should expect, and why I get so much flame from the primary air feed and not from the tubes. We will see what they say....
 

rtrev37

Member
Aug 28, 2018
94
New York City
I tested a few weeks ago. I can do it again when the stove cools down. I use a dollar bill split lengthwise in half. A full bill seems too wide for me. I think it can 'grab' and be tight when in reality there is a section of the door seal that can be leaky.

Please explain why you think it might be the door seal. What is leading you in that direction? I am always trying to learn more.

Hey there, I tried he dollar bill test and failed. However, it did not reduce the secondary air. If not, it woold increase it. I fixed the seal and secondary is still the same. On the HT200O, the secondary is quite impressive. if is restrict the secondary air intake, it will reduce the dancing flames on the stove but contiues to burn at the upper part of the stove, which can not be seen when standing in fron of it.
SECONDARY AIR ON HT2000.jpg HT2000 SECONDARY AIR.jpg
 

Woodcutter Tom

Burning Hunk
Apr 28, 2019
169
Northern Illinois
Ordered a Dwyer Mark II 25 Manometer today. New for under $20.00 with shipping on ebay. Cheapest I have seen . There are more available. When it comes I'll have to get fittings and tubing that won't melt when connected to the stove pipe.
 
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brenndatomu

Minister of Fire
Aug 21, 2013
6,570
NE Ohio
Ordered a Dwyer Mark II 25 Manometer today. New for under $20.00 with shipping on ebay. Cheapest I have seen . There are more available. When it comes I'll have to get fittings and tubing that won't melt when connected to the stove pipe.
This one? That's a great deal.
 

Woodcutter Tom

Burning Hunk
Apr 28, 2019
169
Northern Illinois
This one? That's a great deal.
That's it. It is a Buy It Now. But also Make An Offer. I flashed a shiny $10 bill at him and was approved instantly. $10 plus $8 for shipping plus $1 ish for tax...under $20. It shipped yesterday. Looking at the tracking, I bet I get it tomorrow.
I can't wait to get this thing. Already have the copper tubing.
 
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Todd

Minister of Fire
Nov 19, 2005
9,449
NW Wisconsin
Have you tried shutting down your air sooner? Your flue temps seem high. I like shutting mine down with internal flue temps in the 400-500 range. Unless you have a thermocouple flue probe expect a little delay with the Condar type probes. The actual temps could actually be 100+ more than what it’s reading at that time.

I also think it could still be a split size issue. My stove has a 2.3 cu ft box about the same size as yours and I think mine burns better with splits that are sized to where I load about 8 splits will give me just about a full load with a little 2-3” space above for secondary combustion.
 

Woodcutter Tom

Burning Hunk
Apr 28, 2019
169
Northern Illinois
Have you tried shutting down your air sooner? Your flue temps seem high. I like shutting mine down with internal flue temps in the 400-500 range. Unless you have a thermocouple flue probe expect a little delay with the Condar type probes. The actual temps could actually be 100+ more than what it’s reading at that time.

I also think it could still be a split size issue. My stove has a 2.3 cu ft box about the same size as yours and I think mine burns better with splits that are sized to where I load about 8 splits will give me just about a full load with a little 2-3” space above for secondary combustion.
I have tried shutting the air down at all periods throughout staring a fire. I have tried big movements of the primary air, medium movements, and the tiniest of movements. I do have a thermocoupler attached to a digital readout. It is pretty near instantaneous with the changing temps.
I think the split size is a big part of the problem. I did some testing with larger splits and did not get the primary air igniting the unburned gasses. Later when I was down to coals, I put 6 2 x 2 splits in the firebox (E- W). After a bit the primary air ignited the unburned gasses. When the stove pipe temp was 870 F (at 18 inches above the stove top) I had the primary air completely shut down and the damper completely closed. Within minutes the stove pipe temp was above 1100 F. Once the primary air starts burning the gasses, it is off to the races. The stove pipe reached 1120 F. The STT went up to 600 F. That is the highest I have ever had that temperature. My manometer stayed steady about .08. After 20 - 25 minutes it was all over. The stove pipe temp dropped, the STT dropped.
An interesting thing that happens during this process is that the door glass gets dirty. It starts at the bottom, then gets dirtier to about 1/2 way up the glass. As the primary air stops burning the gasses, and the stove pipe temp lowers, the glass starts to clean up. But only the middle section cleans. The lower section stays dirty and is a chore to clean.
I will be using bigger splits in the future. Not sure how much testing I will get done this year as it has warmed up quite a bit.
Thanks for the help.
 

weatherguy

Minister of Fire
Feb 20, 2009
5,829
Central Mass
I haven't read all the posts in your thread but have you tried the big bio bricks or canawicks to see how it burns with some of those mixed in with the wood?
 

Woodcutter Tom

Burning Hunk
Apr 28, 2019
169
Northern Illinois
I haven't read all the posts in your thread but have you tried the big bio bricks or canawicks to see how it burns with some of those mixed in with the wood?
I did try the compressed sawdust bricks twice. One time added three bricks. Did not generate heat. Next time I added 5 bricks. Primary air ignited gasses and the flames went nuclear. 1st time I saw over 1100 on my flue probe. I got nervous.
 

Woodcutter Tom

Burning Hunk
Apr 28, 2019
169
Northern Illinois
I think I got my stove figured out. I had been emailing back and forth with SBI and trying a few things that they suggested. Finally had a phone conversation with their tech people. We pretty much confirmed what we had been emailing about.

Massive Overdraft. They had suggested that I check my draft with a Manometer. Optimal reading should be .03 to .05 inches of water column. .08 would be excessive draft. My first burn with the manometer installed was around .2 ...... way over the overdraft range. I purchased a damper for the double wall stove pipe and installed it. I did see a difference but it was not enough. I bought two damper plates and installed them in some old single wall stove pipe. I am able to control the draft much better and I see much more secondary flames from the tubes. And more heat from the stove top. I still need to make changes. I might need three dampers. It will be an extensive learning process, since there are so many factors. Each fire will be different, but hopefully I can find a pattern.

SBI told me that with the excessive draft, the air flows so fast that it does not have a chance to get hot in the secondary system, and when it exits the tube holes so fast, it pushes the unburned gas toward the front of the stove. The primary air is hotter and it ignites the gas. When the primary air ignites the gas all the heat goes right up the flue. This causes more draft. The process builds upon itself. The fresh hot air that is suppose to clean the front glass is gone. Thus dirty front glass.

Even though I am running with a 12 foot stove top to chimney cap length, I have massive overdraft. My house sit on a hill. Every direction except to the Southwest is downhill from the building. I get quite a bit of wind. And it all seems to increase the draft, no matter the direction. I can see my manometer reading increase from .05 to .10 just from the wind gusting.

I have more hope than I had a few weeks ago. It was a very frustrating winter. I think I see the light at the end of the tunnel...or is it the top of the chimney? I stopped testing a while back as it is too warm. I want to test when it is colder. The draft will be different in cold weather ( 8 degrees vs 45 degrees.) Next winter will be another learning period. I will need to learn how to control the draft in a variety of situations. Outside temperature, wind speed and direction, and wood will play key roles in how I adjust the draft. The dampers, restricting air intake - both primary and secondary (secondary via the inlet and possible tube restrictions) will be my controls. That amounts to a lot of variables. The goal is to get heat...and I am hopeful that I can accomplish that goal.
 
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brenndatomu

Minister of Fire
Aug 21, 2013
6,570
NE Ohio
The dampers, restricting air intake - both primary and secondary (secondary via the inlet and possible tube restrictions) will be my controls
Did they offer to send their secondary tube restrictors? (basically stainless washers)
 
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