Nepoleon S25 air leak?

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rendatj

New Member
Feb 27, 2022
3
PA
I've been running a new Nepolean S25 non cat stove for about a month and am having trouble keeping the temps and burn time under control. Any medium or full load will burn pretty hot and fast with stove top temp maxing out in the low 800s despite shutting the air all the way down as early as the fire will allow and stove top temp well below 500. The manual says to keep stove top temp under 700. Stove is in a large 750 sq ft room with 14 ft cathedral ceilings, room temp regularly gets into the 80s and I cant seem to get a burn time over 7 hours or so.

Last nigh I loaded it up with large splits of ash over hot coals. I shut the air down early to prevent over-firing and it took a long time for the wood to completely catch but was pretty intense once it did with strong primary and secondary flames over 2 hours after loading. I believe I'm getting too much air unless I'm doing something else wrong. I have a 21ft duratek double wall chimney with one set of 30 degree elbows in the attic. Where do I check for leaks besides the door? Will a loose connection or leak in the chimney affect the fire in the box?
 
The odds of an airleak are small, but possible. How does the door glass look? Is it staying clean? Have you done a dollar bill test on the door gasket and is it sealing tightly? This could be a case of strong draft. A leak in the chimney system would slow draft down, not increase it. Is the 21' of flue measured from the stovetop to the chimney cap?

Post a picture of the stove full of wood to show us how it is being loaded.
 
Glass is clear and clean and dollar bill test shows a good seal. Chimney is 21ft from top of stove to stove cap. Just lit a small about 90 min ago. Including pictures of load and fire at 60 min and 90 min. Nice draft and no smoke from door but had about a minute if smoke coming from the secondary intake. This is the second time this has happened. Its pretty windy so might be related.

Anyway, the small fire is manageable with stove top temp topping out at around 650 and settled now a little under 600. Air has been completely closed for about an hour. I run into trouble when I try and load it for the night. I only have 5 splits in now and double that on reload for the night. Thanks!

[Hearth.com] Nepoleon S25 air leak?[Hearth.com] Nepoleon S25 air leak?[Hearth.com] Nepoleon S25 air leak?
 
I have the same stove but the insert version. I found myself having the same issue. The air intake on the bottom of the stove still lets air come through when fully closed. Maybe 3/4 inch square hole. I used a thick magnet to cover half the hole up. It helped give me alot more control. I gained at least an hour to my burn time. Hope this helps.
 
That may be the boost air hole? If so, that's a good tip. When draft is strong and the wood is dry, boost air can be less necessary.
 
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I'll have to try this
I have the same stove but the insert version. I found myself having the same issue. The air intake on the bottom of the stove still lets air come through when fully closed. Maybe 3/4 inch square hole. I used a thick magnet to cover half the hole up. It helped give me alot more control. I gained at least an hour to my burn time. Hope this helps.
I'll have to try this. I don't see any other holes other then the main intake on the bottom of the stove. There are 2 channels on the the side of the stove that I assume are for the secondary tubes , this is where I sometimes get smoke at startup.

I may be reloading too soon as it only gets away from me when I load onto hot coals, stove top temp 3-400. Any more than 2 splits and it gets pretty wild. I'll have to work on my timing to see if I can get a handle on things but its been pretty warm here so haven't had much oppurtunity to tinker.