Nc30 help-high flue temps

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blackls1z

Member
Sep 22, 2010
25
Brewer, Maine
This is the first real season with the beast and I'm running what seems to be high flue temps - 800-900 (shut down) The stove top gets to no more than 350. I have about a 26' chimney length. Could I be getting to much of a draft? If so what are my options. Thanks all!
 
I much are closing the draft? If you leave it open to much you will get crazy high stack temps and low stove temps.
 
I close it at around 500 flue temp and sometimes will climb up to 800 if I throw a couple splits in. I can only seem to burn two splits at a time in fear of it running away on me.
 
Do close all the way? There was something here about something obstructing the the damper from closing all the way......hmmmm. Also there is a hole in the back of the stove that you can partially block to control the temp. That is the inlet for the secondary tubes. Make sure the ash plug is sealed tight with ash.
 
Need some info here. How are you loading the stove and with what? Where are you measuring that stove top temp and with what? And a statement. 900 flue temps during off gassing on a fresh large reload is no problem. Quit closing it down so soon. Burn the stuff in the stove not in the pipe.

PS: And make sure those baffle boards are pushed together with no gap between them in the middle.
 
Should I be more focused on the stove temp and not the flue temp? Once the temp on the flue starts to climb I shut it down. What is a safe temp for the stove top?
 
My 30 cruises between 550 and 650 stove top.
 
My 30 cruises between 550 and 650 stove top.

Same here.

I agree. Check the baffles to make sure the only opening is across the front of the stove. 26 feet is pretty tall, so you may have a really good draft.

Your stove should have no problem cruising at 500+ stove top.

-SF
 
I don't have a thermometer on any flue. The stove is what heats my house. Not the pipe.

If you have been burning that stove at 350 stove top I would get a look down that chimney. Real soon.

Now, the same questions:

"Need some info here. How are you loading the stove and with what? Where are you measuring that stove top temp and with what?"
 
I load the wood which is a mix of poplar and oak. I load it n-s. I have a magnet type thermometer left of center on the lower tier of the stove top. Right now the stove top is running at 475 so maybe I'm not as far off as I thought.
 
My stove top therm is stuck right in front of the pipe on the upper tier. Like the others, when cruising it is 550-650 stove top with 700 not out of the question. This is with my air closed 100% - or as 100% as the EPA allows but I have the rod pushed completely in. Also, like BB, I have no clue what my pipe temps are?? Pipe is DBL wall so an IR would not work and I don't want to drill a hole in it to install a probe. With a 26' chimney I would suspect great draft - I only have 16' but there are plenty of other factors to draft.

The baffles are the light weight white boards inside the top of your stove above the 2ndary tubes. During shipping or with careless log placement that can get moved around leaving a gap that allows to much heat to go up the stack. Next time it cools down a bit take a look and make sure they are tight together and there is no gap at the rear. Many, myself included, have done a mod that fills the gaps even tighter by pushing them to one side and placing a rod filled piece of rope gasket on the other side, parallel to the baffles. This is not a necesary mod but simple and helps a bit. Second check point is the plug that is a PNTA - make sure it is in place and there is plenty of ash filled in around it to plug any air leaking gaps. Keep the ash drawer shut. A better solution to this is take the darn thing out and replace it with a tight fitting piece of fire brick. If you think the plug is causing over draft issues you can try leaving the ash pan filled and this should help as well. My ash pan is just cosmetic or as BB says, "a great place to warm hotdog buns!"

Both of these ideas were mentioned above and this is where I learned them first so no new news here - just more details.

Lastly make sure you are burning dry wood. As with any EPA stove it is going to perform best with >20% moisture.

If none of this helps give us a better description of the entire flue set-up? Straight up through house, DBL 90 and out the wall, etc... This may help with a diagnosis.
 
Thanks guys. I just checked the baffle boards and one was overlapping the other and not resting down on the tubes like the other one. No clue how long it's been like that. It may be too early to tell but it seems that may have been my problem. I have a decent blaze going with stovetop close to 500 and the flue was starting to creep up so i just shut it down and the flue temp is heading down now which wasn't really happening before. Thanks guys!
 
since I installed my 8 inch ss liner I have to pay very close attention to the air lever when cat not engaged.
My habit now is not too run air wide open or probe will hit 1100 and stove only 300.
If I keep air open just over half the probe rises slower as stove top gets too 500 with out turning the liner red !!!
 
I don't have a thermometer on any flue. The stove is what heats my house. Not the pipe.

If you have been burning that stove at 350 stove top I would get a look down that chimney. Real soon.

Now, the same questions:

"Need some info here. How are you loading the stove and with what? Where are you measuring that stove top temp and with what?"
I think that is bad information, in some conditions I would have a glowing stove pipe before I get the stove top up to temp, it has nothing to do with what heats your house.
 
This is the first real season with the beast and I'm running what seems to be high flue temps - 800-900 (shut down) The stove top gets to no more than 350. I have about a 26' chimney length. Could I be getting to much of a draft? If so what are my options. Thanks all!
Sounds like you fixed your problem but I did not see if you had a probe or surface thermometer on your stack
 
Make sure your ash pan is closed tight and also make sure your door doesnt have any leaks. i have noticed on mine that if the ash pan is not closed tightly the stack temp gets really hot. Also i had a big scare last year where i left the door open about a quarter of an inch to give it more air since my wood wasnt catching on an got distracted and the stack got really hot and burned off some buildup and the house got full of smoke. Also i noticed that if i load n/s it burns faster than e/w so try loading different ways. good luck pal.
 
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