40 foot chimney

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riverat

Burning Hunk
Oct 30, 2014
116
bainbridge,penna
Hello folks,i would like to upgrade to a blaze king ,king model stove and called blaze king and they told me the chimney is way to high to operate there stove,i had this chimney built this year in September with 2 flues in one large block setup.one for oil and one for wood that I made a sketch of on my post here,i have good draft even with the flue being on a 40 deg angle to the straight line,i can blow out a fireplace match and it will suck the smoke up from 2 inches away where the flue comes out of the wall inside so I guess that's plenty of draft ? this is my first time owning a wood stove so I am a green horn on what would pass.i would be very happy if folks here could give me ideas on astove that better then the old Alaskan stove that I have working now,i would like a stove that I can burn for more then 2 hours until I have to add wood like I do now


hope you guys can help me out before it really drops temps here in Penna


thank you

Jeff
 

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A key damper is almost a certainty for this installation. Maybe even two. Are you set on heating from the basement or would a stove on the main floor (with a shorter chimney run) be acceptable? What is the wood stove flue tile size?
 
thank you Begreen for the reply, I am setup for heating from the basement only,i opened the cleanout door and it measured 6 inches inside, the builder of the chimney has a 8 inch crock inside feeding the 6 inch in the chimney.my stove has a 6 inch exhaust sure hope there is more folks like yourself looking over my need of information. picture of stove I have now


Jeff
 

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Did you ask the BK tech if it would be ok if with a key damper (or two) installed? Have you contacted Buck with the same question?
 
I put a key damper in my 2+ story setup. No idea the actual height. I have an ashford and have not gotten the burntimes I want. Will keep at it.I'm still learning.
 
I guess that's plenty of draft ?
The problem is that it's too much draft. Most stoves are designed around much shorter flues. A draft that is too high will not allow you to control the fire, leading to overfire conditions. Usually, a flue damper can tame the excess draft to allow a stove to operate normally. I would think that you could find a solution consulting with various manufacturers.

Another solution that is sometimes used is adding air restriction to the stove intake, but that modifies the stove and is not always recommended. But it is done.
 
I live right up the road from you in etown... Definitely don't have a shortage of wood around here.
 
Want to thank everyone for the replying back on my post,to Begreen I didn't contact buck stoves but will do that, and to tiwvr1 glad to here you have plenty of wood to your disposal, if you get overstocked and run out of room I would be glad to stack it at my place ♨️

Jeff
 
I have a 24' chimney installed thru the house. On my PE spectrum (super 27) it would regularly overfire last winter until I modified (bent) the stop tab to shut it further. Works great after the mod, but on warmer days I need to make sure I don't turn it down too low and smother it. On cold days (under 10°) I can turn it down to where the damper (seen underneath) is nearly completely shut and it will run hot with good secondaries.

Do a search on 'florida bungalow syndrome'. There is a web page that has good info on that related to tall chimneys on new stoves.
 
I have a 24' chimney installed thru the house. On my PE spectrum (super 27) it would regularly overfire last winter until I modified (bent) the stop tab to shut it further. Works great after the mod, but on warmer days I need to make sure I don't turn it down too low and smother it. On cold days (under 10°) I can turn it down to where the damper (seen underneath) is nearly completely shut and it will run hot with good secondaries.

Do a search on 'florida bungalow syndrome'. There is a web page that has good info on that related to tall chimneys on new stoves.
This is what I was referring to also. Designers of new stoves that must meet EPA requirements have to design around a typical draft situation. That situation seems to revolve around a flue height of around 15' but can work up to maybe 30' plus or minus.. Part of the design criteria is the minimum allowable air intake. If a new installation draws too hard, then the owner may not be able to turn the air down enough. Designers have to draw the line somewhere.

There are two ways to try to solve an overdraft problem. One is to restrict the flue by way of a key damper. The other is by modifying the air intake (like lindnova above did) and others have done. Many would argue that the technically correct solution is to restrict the air intake, the argument being that the stove designers simply didn't allow for extreme draft. But the most common solution is the flue damper if it can be implemented.
 
When I spoke with Jeff, I was most concerned that the stack temps would never hold up. First, a 6" chimney with the King model is not anything we will endorse...been down that path many times.

Second, the heat loss up the stack would disappear long before the top of the chimney.

I recommend a less efficient appliance, one with a robust build quality that can handle hot fires while delivering enough flue gas temps to keep the chimney functioning correctly. Kuma makes some tanks that could perhaps deliver on both fronts.

Of course we like to sell stoves, but satisfaction and great performance is paramount.
 
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To BKVP , thank you for being honest and not trying to be a back alley used car salesman, you have displayed good honest customer service with someone that doesn't own your product and you came thru and I thank you for that, I am so confused on spending a few thousand dollars on a stove that won,t be any better then the 30 year old Alaskan Kodiak that I am burning now, I am hoping to get more then 1-1/2 hours of burn time with the stove choked back on the damper and the front air draft knobs all most closed, would it be better to have a stove supplier come in and access my setup hoping they could come up with a game plan to assure me the right setup would be better then what I am running now? I really like the looks of the kuma stoves but see very little ownership of this brand here.


Can,t thank you all enough for reaching out to me in need of help for a green horn

Jeff
 
Wow now thats a tall chimney. Maybe a pellet stove would have been easier in this install with more flexible venting options. Hope you can come up with a good option.

The problem is that it's too much draft. Most stoves are designed around much shorter flues. A draft that is too high will not allow you to control the fire, leading to overfire conditions. Usually, a flue damper can tame the excess draft to allow a stove to operate normally. I would think that you could find a solution consulting with various manufacturers.

Another solution that is sometimes used is adding air restriction to the stove intake, but that modifies the stove and is not always recommended. But it is done.

I have some slight overdraft problems just with my 24' duravent on my insert. Being an insert, I don't see how any kind of damper in the exhaust is possible. Of course one could create a restriction and just leave it that way always, but thats not ideal either.

You can restrict the primary air intake by doing some machining to my stove, but of course that voids the warranty and all that. I kind of wonder in the extreme case of your house burns down how a homeowner-modified stove is viewed upon. The other problem with modifying the intake is the secondary air. And I think that is what gets me since when mine overfires (or maybe not overfire just going way too hot) its when the secondaries are running like blow torches on good dry black locust. The secondary is completely unrestricted and open and allows how ever much air to come in as the draft is pulling. This is on the back of my stove inside the fireplace cavity so again not reachable. If I had to do it again I would not go the insert route - to limiting, and seems to waste a ton of heat, or at least the radiant effect.
 
The tall chimney is challenging but not impossible. I would install with a key damper and possibly consider a slight modification of the air intake stop to allow it to close further. You should be able to get decent burn times with a good 3 cu ft stove. It may actually take two key dampers if the draft is huge. In that case one may be left in a permanently closed or partially closed position.

Although the current setup may be for a basement install, I would still consider the option of tapping into the chimney on the first floor, installing a proper and safe wall thimble, and placing the stove on the first floor. In that case an unmodified stove may work out well including the BK.
 
Hey guys would a new non cat stove with a 8 inch exhaust help tame the draft versus the 6 I have now ? Just fishing for more information that a greenhorn lacks

Jeff
 
Hey guys would a new non cat stove with a 8 inch exhaust help tame the draft versus the 6 I have now ? Just fishing for more information that a greenhorn lacks

Jeff
Generally, the taller the flue the smaller the pipe you can use. Depends upon configuration, materials, etc but a bigger pipe is rarely the answer.
 
Thanks jackfre, today I started up my stove and had to keep the door cracked so the wood wouldn't smoke, my question is when I bought the stove used there wasn't, a sign of a door gasket on so I put one on ,did this old of stove have gaskets on it back 30 plus years ago? Should I remove it and try it without ? I am guessing that the strong chimmey draft won,t allow enought air thru the front air knobs even backed out.when I shut the door you can see the flames drop down and it starts to make puffing sounds but smoke doesn't come out the front air knobs, the more I think I can run the stove with the same settings the more I keep scratching my head the air knobs seem like they sit pretty high up from the bottom of the fire box. I am hoping buying a new non cat stove will help me with some of my draft troubles, hope you fellas don't get tired of seeing my post up towards the top everyday you come to this forum I am lost on what my next step should be to make this stove work.

Thanks fellas with putting up with me so far

Jeff
 
I'm sure you can find a good non-cat stove that you can make work with that flue even if it takes a damper or two to tame the draft. An Englander 30 perhaps at 3.5 cf?

I nearly mentioned the Kuma Sequoia, but I see it's an 8" flue.
 
Well I have a new NC-30 coming tomorrow, hope I can control the draft better then my old Kodiak stove, I can,t help to get high flue stack pipe readings that run up to 700 degrees when I reload each time. Now that it's in the high 20s at night here in penna it burns my reloads up in a hour, I am really frustrated with trying to maintain a stove every hour, if anyone has any ideas on how I should set up the NC 30 please I am open for any ideas you might have, a friend told me to stand a fire brick up in the crock just as long as I pull the flue apart and inspect it often, not sure I like that idea
 
Thanks mellow for the reply,I just got off the phone with Mike at England stove company and we had a long talk , great fella to talk to, he also said that I will have to put a key damper in witch I already do if you look at my picture at the start of my post,I sure hope. and pray this NCH 30 will be a improvement over what I have now. I forgot to disclose that the baffle in the fire box is very distorted Hanging down away from the flue opening. I bought this stove used at a yard sale. guest it shouldn't used it for a boat anchor. Mike said this stove is scrap do to the baffle inside being really distorted from someone abusin it.

Jeff
 
I installed the NCH 30 a few days ago, can,t get heat above 450 f stovetop temp, can keep the door closed and the secondary tubes are working and are cherry red, my flue temps are almost the same temp as my stovetop, my splts are 5 inches and stacked straight in, I just can,t seem to understand why my coals won't burn to a finer size, I have to remove red hot coals so they don't keep getting higher, have Anderson chimmey sweep coming December 4 to check out the chimmey and give me there opinion on how if any improvement that I can make on the 40 ft monster do any of you folks think I might need to go to a liner?


Thank you

Jeff
 
Jeff, look at my thread from yesterday "Moved stove - problems with coals. it may help you
 
Thanks Kenny, i believe I am in for a tuff time with what i have to work with, I sure hope the fellas from Anderson chimmey service can see something that I can change to help out with my problem. I spent thousands of dollars between a new chimmey and a purchase of a new stove this fall, I surely wish someone can figure out the problem without spending much more money I don't have at this time

Jeff
 
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