Install complete and chimney cap caution

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Zamfir

New Member
I am finally finished with my install and I would like to add whatever I can to this great resources knowledge base.A quick summary of my setup.
Stove is nc30
Unfinished walkout basement install
About 5 ft. Of double wall stove pipe
Thru the wall and up 24 ft. Of class a
Supervent.
Home is drafty chalet style hunting camp
With huge windows and existing propane furnace.
About 2200 sq ft. Including basement

I've been up and running about a month now. My first half chord of wood was 12 to 15 on the mm. I had no problems getting fire started and man it burnt well. Almost too well. 600 for stove top temp was easy, I had a couple soar up around 750.
My next batch of wood was 16 to 19% and wasn' quite as predictable. One attempt at an overnighter left me with blackened glass in the morning.I think I either turned it down too soon or I closed my air too much.
It burned pretty well for another week and then a couple things changed on the same day....a low pressure event moved in, and I fixed some basement leaks with a can of Great Stuff.That day the draft started seeming week and it started to smell a bit In the house.
I rationalized it as the changing weather, and I also started cracking basement windows but each day it seemed to be worse with the smell. Then it started to smoke from my stove pipe seams when I reloaded.
Then that same night, after 2 and a half weeks of operation my co2 alarms went off at 3am ....I shut her down and started reading everything I could, all signs pointed to a blockage,including the threads on this site, yet I thought that was impossible so soon.
For me, the bottom line was this, I thought I was being clever by putting my own screen in my supervent chimney cap. I didn't want any critters coming into my chimney.....especially rodents,....I don' like rodents. I made my screen from half inch hardware cloth, (similar to chicken wire) .
I finally went up and checked my cap and was blown away by what I found, 1 side of my screen was 100% closed, the other side was about 75% closed.(kind of like my heart after my last heart attack..lolo) In 2 and a half weeks these half inch holes were completely sealed...unbelievable,
I am thankful that I had all of the threads about poor draft on this site, to finally make me go up and check. And this all happened with pretty good wood. I think my biggest problem was operator error, specifically, turning down the air too much and too soon.
I wonder if those burners with cold outdoor chimneys should even close their primary air all the way, seems like the top around the cap gets cold when you get down to Coaling stage.
I want to emphasize the importance of co detectors, they very well may have saved our lives. Please be careful if you have pest screens or spark arrestor in your cap.
And by all means, listen to those with experience on this site.operating these stoves is a gradual learning process and reading will only take you so far since each stove and situation is as varied as human fingerprints.
There is a few things I would like to emphasize for you newbies.
1: don't use cap screens unless you have to.
2: USE CO DETECTORS!!
3.use a moisture meter so that you KNOW....not think.....that your wood is acceptable.
4: practice your all nighters in the daytime when you can monitor it.
5: make sure you have safe and easy access to your chimney and cap...you won' check it enough if it is scary for you to get up that high. ( I myself must get a taller ladder).
Thank you all for your time, and to end on a high note I must say that I really love this stove, it is an impressive heat maker but you must learn how to use it. I hope my photos w.
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Premium write up and evaluation. Thank you for sharing.
 
Good advice. One thing I've noticed over the years is that there is usually a good reason for almost anything unusual that occurs while burning your stove. My two stoves both have good drafts. If I ever open one of their doors and even a whiff of smoke comes out I know right away my cap is getting clogged. It doesn't take muck creosote buildup in the cap to do this, so it's a good safety alarm to go clean the cap before it gets to a dangerous level.
 
My chimney and roof are easy to access, so I like to check the cap once a month or so after reading so many horror stories on this forum.

I couldn't agree more with experimenting with "overnight burns' during the day to really get a feel for them and be able to monitor. The first few times I packed the stove, got up to speed, and shut all the way down before bed had me pretty paranoid. Wood quality is crucial for running your stove this way.
 
My chimney and roof are easy to access, so I like to check the cap once a month or so after reading so many horror stories on this forum.


Mine is easily visible from ground level, so I check in more frequently. Easy to do, and good insurance. Easy to access for cleaning, too. Not much pitch, and an easy climb up, so I can clean often. I need to because my stove is oversized for the house and gets run throttled down most of the time.

Good write up. That cap can give grief.
 
My install also allows me to inspect and clean often.. I have two 90 degree bends that I have drilled and plugged some access holes in for cleanout of flyash that settles in their corners and my 4foot of horizontal flue.. I don't have much creosote except my home-made top-cap does collect a little. My flue is around 8 feet total vertical with 4foot of horizontal. (not optimal indeed), and sometimes im forced to use semi-seasoned wood...im sure my firewood available and your 24 foot flue would not get along very well.
 
That's a common issue the first few years. The wood is just not seasoned. My cap was a gooey mess in 2 months. The 1/4 inch screen was plugged up. I removed the screen. The cap being cold is the issue. Years latter with the same stove the cap gets about the same build up as the inside off the chimney.
 
excellent post
 
Thanks to all for comments, but all I did is repeat advice that I found on this forum, so thank you to all op's. I started stove back up last night for 1st time since and WOW, what a difference. When the nc30 is being opera ed properly it is like a nuclear incinerator!
I wish I had taken a photo of the cap and screen but I was focused on getting down off that ladder. If I remember correctly tho, I believe the windward (west) side was sealed shut worse than the east side of the cap.