Top down fire

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I've tried the top down method a handful of times and do like it but I've run into some issues. I'm able to get the fire going with secondary burns but when the fire starts working it's way down to the bottom logs coals pile up and the bottom splits turn black and it starts smoldering. The flue temp drops into the creosote buildup temps and I'm having to tend to the fire more, closing and opening the air control. Theres no way i could turn the air down like i normally do with a bottom up fire and let it go for hours at a time. Any suggestions?
 
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How did you measure the moisture content?
Moisture meter on a fresh split. Last year I bought two cords of kiln dried mostly debarked oak that was typically no more than 13%. It would light very easily and have never loaded my stove more than half way, even with temps in -30s df.

I'm wondering if my box isn't loaded full enough for a top down. I typically do three splits on the bottom and two more on top when I tried that method, trying to create a flat surface where I light up kindling and throw some splits on. Maybe my issue is there isn't enough fuel on top for the coals to burn the bottom row?
 
I never throw splits on a top down structure. Fill the box, kindling on top. Start the fire, and only open when you need to reload.
 
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The benefit of the top down is it warms the top of the firebox faster. If the flame isn’t at the top, it would defeat the purpose. Try to move the splits up higher, I use some spare firebricks, in the firebox.
 
I never throw splits on a top down structure. Fill the box, kindling on top. Start the fire, and only open when you need to reload.
If someone is trying to establish a coal bed first, then a top-down start on say 4 splits is not uncommon, especially in milder weather. After that putting a few splits on the coals to maintain the fire will keep the stove output on the low end.
 
I guess that's the trouble others have to go through for a low output then.
 
I guess that's the trouble others have to go through for a low output then.
Not much trouble, and a pleasurable exercise for many. It's easy and the way many Europeans like to run the stove, my wife too.
 
If someone is trying to establish a coal bed first, then a top-down start on say 4 splits is not uncommon, especially in milder weather. After that putting a few splits on the coals to maintain the fire will keep the stove output on the low end.
I've been mulling over this. I think it's not different from what I said, other than how full the firebox is stuffed (due to the differences in low-end output limits for different stoves).

"Establish a coal bed first and reloading with a few splits" just means burning a partial load down to coals, and reloading with a partial load. I.e. the initial, "light-off" load is of the same size as the intended reload load.

I do the same, other than having the initial light-off load being a full firebox with one half-sized split on top where I start my top-down fire, and the reload also being a full firebox.

My main point was: don't do anything different regarding the load in the firebox at lighting time as you would for a reload. The load at both times should be of the size you need for the amount of heat you need. I.e. lighting the fire should not be anything different regarding load quantity than a reload. It should only be dictated by the heat you need.

Does that make sense?

(I do see the "need the secondaries going" as putting a lower limit on how much wood in the box would work, i.e. putting a limit to how low the heat output can go - but that is a different issue, and just a characteristic of the (type of) stove one has.)
 
Can you post a pic of your top down load before u light it? I'm Sure that will get you the answer to your issue.
 
Can you post a pic of your top down load before u light it? I'm Sure that will get you the answer to your issue.
Here’s a modified top down fire from the spring. I’m not saying it’s perfect, but it worked for me on this day. I think I have three decent sized splits in there with some construction debris as kindling on top and a bunch of Newspaper.

Top down fire Top down fire
 
Here’s a modified top down fire from the spring. I’m not saying it’s perfect, but it worked for me on this day. I think I have three decent sized splits in there with some construction debris as kindling on top and a bunch of Newspaper.

View attachment 300643 View attachment 300644
Yeah Ok we can definitely do better than that. I'll take some pics next time to show a perhaps more reliable simple set up.
 
I've been trying the top down fires this year. They have pros and cons. I find top down less maintenance but doesn't burn as hot. My flue Temps spike and my firebox is still not filled with flame, so I close down. I then find that I'm having to open up again in a short while once flue Temps begin to drop. At this point I can leave the fire for a while and all is well. Also, I hear others saying their secondaries are firing. From the video I saw, yes the secondaries are firing, and mine do too but nothing like they fire during a long burn once my fire is truly established and the heat is up. My secondaries fire down 6-8 inches. They're beautiful because they're almost bluish. I'm not sure if the initial top down fire is 'true' secondary burn.

I generally do a modified top down with two medium-large splits on the bottom and then two smaller splits on top in a hash tag formation. Followed by kindling on top. Once the kindling has burned down and the bottom splits are burning, I then fill the box. I find this method is a bit more maintenance buy you get a better burn.

I'm still trying g top down though cause it's just fun and new but I definitely find my modified approach a bit better.

Heres my top down:20221006_164429.jpg

This next one burned well: Top down fire
 
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I think any method that makes the secondaries appear fastest in your system is a good method.
A lot depends on the type of wood and its dryness (in my experience), and on the air flow in the box (stove design). So don't try to use a set method "because it's been prescribed" that way - just make it work the best/fastest for you.

That holds about for everything with stoves (i.e. models, cat or tube, wood stacking/storing habits, etc. etc.).

My $0.02
 
It looks to me that the second pic allows more air flow thru the splits in your stove. This will definitely help faster starting. Keep trying different set ups and soon you will be able to dial in exactly what you are looking for. Ex. Fast start vs long burn time before reload. (And everything in between).
 
Here is 1 way to top down in Jotul f400. Wood is oak and random twigs/ sticks.

Start 9:33 A ...... Door closed tight at 9:35A.......Stove pipe at 400F at 9:47A and draft shut 1/2 way.
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400F on pipe at 9:47A.
 
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