Measuring Chimney Draft

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You are saying you have a clay liner from the thimble to the roof? Most masonry from the smoke chamber open up then go to clay liner yours?
Yes however, there are two other lower thimbles not in use that go into the chimney below the beginning of the clay liner. Those two other thimbles are at chest and chin height and 90 degrees apart. The center of the thimble the stove uses is at about 6'4".
 
If the cat stoves throw very little heat up the flue how does creosote not build up quickly? Is it because the secondaries burn the ash so fine?
 
If the cat stoves throw very little heat up the flue how does creosote not build up quickly? Is it because the secondaries burn the ash so fine?

It's because the products that condense and form creosote are burnt in the stove and provide heat. There is little or nothing left to form creosote.
 
The moisture in the wood does not get consumed. It will always find its way up the chimney and will condense and form creosote if the flue gas gets cold enough. Moisture from the air takes the same ride and will add to the moisture in the flue.

Keep in mind that the stove manufacture considers 20% moisture the maximum amount. Burning wood that dry and dryer helps to limit the creosote buildup. The fact that my chimney doesn't have any until the upper 1' section tells me I have enough thermal insulation to keep it from condensing lower in the chimney. Or rather, enough heat is going up the chimney to keep it from condensing.

The cat and flame arrestor keeps ash and particulate from going up the chimney. My old stove drafted so hard it could probably suck up a golf ball. It didn't have a baffel in the firebox and sent a lot of heat up the chimney. I also had a lot more ash in the chimney when I cleaned it.
 
There are two other lower thimbles not in use that go into the chimney below the beginning of the clay liner. Those two other thimbles are at chest and chin height and 90 degrees apart. The center of the thimble the stove uses is at about 6'4". The two lower thimbles not in use? are they capped off? So there is OPEN SPACE gets wider from the thimble to the clay liner. I see four metal screws at he top of chimney where the cap went on! Is there a cap full of cero? I had the same problem from my dealer (lack of knowledge) till I got educated
(firewood forum) and straighten out. Highbeam has been a good help knows his stuff Chris at BK give him a call!
 
***Blaze King recommends the use of a Stainless steel liner, preferably insulated, inside a masonry chimney. is to maintain proper dra and overall better operation of the unit.
This is in the manual from BK
 
There are two other lower thimbles not in use that go into the chimney below the beginning of the clay liner. Those two other thimbles are at chest and chin height and 90 degrees apart. The center of the thimble the stove uses is at about 6'4". The two lower thimbles not in use? are they capped off? So there is OPEN SPACE gets wider from the thimble to the clay liner. I see four metal screws at he top of chimney where the cap went on! Is there a cap full of cero? I had the same problem from my dealer (lack of knowledge) till I got educated
(firewood forum) and straighten out. Highbeam has been a good help knows his stuff Chris at BK give him a call!
I spoke with Chris. He had concerns about creosote buildup. Please go back a page, or to the beginning and read about the specific issue I ran into. I don't want to rewrite everything. The cap did have some creosote but it wasn't bad. I will live with some on the cap and upper foot of chimney.
 
***Blaze King recommends the use of a Stainless steel liner, preferably insulated, inside a masonry chimney. is to maintain proper dra and overall better operation of the unit.
This is in the manual from BK
It will all become clear to you why I dont have one if you would go read from the beginning. Either you haven't done that or your comprehension is poor. I don't mean to be insulting but you are not telling me anything I don't already know.
 
Did the installer know that BK requires SS liner? This could be a deal breaker for you saying your were not informed and this is what I do not like about dealers selling stoves with no expertise on EPA stoves. Sorry I will go back and read ALL your posts
 
I read all of your posts and looked at pictures of the chimney with the cap off shows what looks like two chimneys higher than center one.A backup picture showing more of the chimneys would help! If so not up to code but if you go to the big box store purchase a 3ft extension and slam a pipe into the center chimney see if this helps. Did you get IR readings? Del who Del taco? https://www.firesidechimneysupply.com/rectangle-to-round-adapter.html
 
I read all of your posts and looked at pictures of the chimney with the cap off shows what looks like two chimneys higher than center one.A backup picture showing more of the chimneys would help! If so not up to code but if you go to the big box store purchase a 3ft extension and slam a pipe into the center chimney see if this helps. Did you get IR readings? Del who Del taco? https://www.firesidechimneysupply.com/rectangle-to-round-adapter.html
read post 69.......:dizzy::dizzy:
 
I read all of your posts and looked at pictures of the chimney with the cap off shows what looks like two chimneys higher than center one.A backup picture showing more of the chimneys would help! If so not up to code but if you go to the big box store purchase a 3ft extension and slam a pipe into the center chimney see if this helps. Did you get IR readings? Del who Del taco? https://www.firesidechimneysupply.com/rectangle-to-round-adapter.html
I cant follow what you are saying. My chimney is up to code. It's a masonry block chimney with a 8x8 clay liner. At the roof where is exits there is a vent for a propane insert (on right in pic). Those two are completely separate. They both are about 3 ft higher than my highest peak of my roof.
I didn't get a chance to do the IR images.
I don't understand your suggesting for adding a pipe. The clay lined chimney is dedicated to the woodstove...
2010-10-08_10-46-09_576.jpg
 
There ain't no magic... never has been.
I hate to sound like a broken record... but... you flat cannot burn less fuel, over a longer time period, and get the same per-hour rate of heat generated... it ain't possible.
Marshy, I'm seriously sorry you're having troubles, but you're attempting to use what amounts to a space (room) heater to heat more space than it can... the more space you heat, the higher per-hour rate of heat output needed, something that cannot be accomplished in an appliance designed to both burn less fuel, and burn it over a longer time period.
Been there... tried that... failed.
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Efficiency efficiency efficiency
 
Efficiency efficiency efficiency
A Ford Fiesta is fuel efficient... but you ain't gonna hook your loaded 16 ft trailer to it.
Efficiency is worthless if it cannot provide the power required to do the job.

You flat cannot burn less fuel, over a longer time period, and get the same per-hour rate of heat generated... it ain't possible.
There ain't no magic... never has been.
*
 
You flat cannot burn less fuel, over a longer time period, and get the same per-hour rate of heat generated... it ain't possible.
There ain't no magic... never has been.
*

Lord knows I could be wrong...

I believe the shtick with catalytic stoves isn't that they are burning less fuel, its that they are burning all (or most of) the fuel.

You can see it even with a non catalytic stove that has secondaries over one that doesn't, or compared to an open fireplace. Less smoke out of the end of the chimney equals more fuel being burnt in the firebox.
 
I agree with Casey. Getting more heat out of the fuel that is being burnt meant more heat into the house per volume of wood consumed. The end result is you burn less fuel to heat the same space. The BK King has one of the largest fireboxes on the market for free standing stoves. Implying it is meant to burn less wood for loger periods of time I feel is inaccurate. It's meant to hold a lot of damn wood and provide a long burn time. It achieves that through a more even heat output because the thermostatic air damper and burns more of the available fuel because of the cat.

You could take two stoves, one is BK King and the other has the same size firebox a similar thermostatic air damper but has no baffel no secondary burn or cat, load it to the same amount as the BK King and get more heat into the living space and a loger burn from the BK stove. That is a fact.
If you looked at the heat transfer rates of each of the stoves I have no doubt the older stove will throw more BTU/hr into the living space in the first two or three hours. However, if you look at what happens after hour 3 in the burn cycle the BK will still be chugging along where the older stove is coasting.

I know this because where I would have to load my old stove with half a dozen or more large 6" wide splits ever 4 hours I can load only four medium 4" wide splits and get nearly the same heat.
 
Lord knows I could be wrong...
I believe the shtick with catalytic stoves isn't that they are burning less fuel, its that they are burning all (or most of) the fuel.
Let's take the Blaze King in question... with a efficiency rating of 88% LHV/82% HHV. Now let's say under real world conditions/operation the operator actually gets 85% (I believe I'm being generous). We load the stove with 50 pounds of wood and use the value of 7000 BTU's per pound (just picking numbers for comparison... it doesn't change the result).
7000 x 50 x .85 = 297,500 BTUs.
Blaze King says the stove will run for 12 hours on the high setting. (Are you gonna' run it on high??)
297,500 / 12 = 24,791 BTUs per hour (averaged).
Now lets throttle it back so it runs 16 hours...
297,500 / 16 = 18,593 BTUs per hour (averaged).

Now let's take an older style stove and say we can get 60% efficiency from it.
7000 x 50 x .60 = 210,000 BTUs.
Most any older style stove will run 6 hours without any problem (my DAKA furnace will easily).
210,000 / 6 = 35,000 BTUs per hour (averaged)
And let's throttle it back to run 9 hours...
210,000 / 9 = 23,333 BTUs per hour (averaged).

Notice the older style stove produced 10,000 more BTUs per hour of run time... but ran a shorter time.
Another issue with the newer style is the heat output is not as consistent over the entire burn cycle... the output drops way off late in the cycle (however, I don't have experience with cat stoves in that respect).
It is not possible to do both... burn less wood, over a longer period, and get the same per-hour rate of heat generated.
Even at 50% efficiency the older stove makes more heat per hour.
7000 x 50 x .50 / 6 = 29,166 BTUs per hour.
7000 x 50 x .50 / 9 = 19,444 BTUs per hour.

And that's just figuring the burn cycle time... when you start saying your loading less wood and burning it over a longer time... the numbers look a whole lot worse.

If the newer, higher efficiency stoves will produce the amount of heat per hour that you require... the efficiency is wonderful and great.
If they cannot produce the amount of heat per hour that you require... all the efficiency in the world is worthless.
Just as you'll get great fuel efficiency in a Ford Fiesta... but it won't pull your trailer.

There ain't no magic... never has been.
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