Small firebox management

[Andy S.]

Those of us with small fireboxes are always going to do more work than the big boys, but I'm wondering if there is a rule of thumb for the size of the splits? It seems that the standard 3-4" split would perform differently in a larger firebox than it would in my little 1.4' firebox. Is it proportional? I plan to try it, but wonder if others have already tried re-splitting to be able to mimic big-box proportions?

 

[Therivermonster]

I would also like to learn more about this due to recently starting to burn with a Jotul F3.

 

[Huntindog1]

Use your search on this forum and look up Rake your Coals Forward technique.

 

[HotCoals]

I'm curious to know how the eco bricks work in smaller stoves. I have a feeling they would work better in a smaller stove compared to my king. Takes way to many to fill mine up even half way and a few like 20# worth look like nothing in there.

 

[Andy S.]

Use your search on this forum and look up Rake your Coals Forward technique.

Your firebox is 2.2x mine and the issue of raking the coals forward is part of why I ask the question. Coals management is a huge issue for me. Raking them forward results in barely being able to get a 4" split by the remaining opening. I end up running a few Pine splits between loads of hardwood just to be able to reload.

The theory is that running splits that are 2-3" would make it similar to running your stove. It would require twice the work on the front-end but make running the stove more efficient.

 

[Huntindog1]

Coals is an issue when pushing the stove hard. Your stove is smaller so you most likely push it hard. I had a 2.12 cuft stove previously.
Raking coals forward is a trick to get longer burn times as you have a spot in the back of the stove after raking coals forward to put wood thats not laying on hot coals. Being able to lay wood directly on the bottom of the stove means you can load more wood in the back to compensate for less wood loading in the front. During last winters very cold temps I just shoveled out coals into a coal bucket and dumped them into a coal pit out back of my house just so I could get a full load of wood in. When temps are really cold like minus temps I had to take action to keep the house heated. We really only have two option wait for coals to burn down or remove some of them. Removing coals maybe your only option especially if your dealing with a small stove.

Also Check this info out:

http://www.woodheat.org/charcoal.html

 

[prezes13]

I learned that eco bricks were great to burn coals, providing a lot of heat

 

[Huntindog1]

Too answer your question on split size, I would think larger splits would burn longer. Smaller splits might leave you less coals but less burn time.
Maybe you can experiment and see what happens , I am sure people on here would love to learn more about coal management as we all have had issues.
I think it may have to do with the insulated fire boxes as the article I gave a link too in my previous post eluded too.

I say that as in my previous stove I insulated my firebox by putting ceramic 1/4" insulation behind all my firebrick sides and bottom of the stove. I also added extra insulation on top of my baffle board. This seemed to improved the operation of the stove with quicker heating up the box and letting me turn my input primary air down to lower levels and still maintain secondary flames in the top of the stove. What I also noticed was when I opened the door for reloads alot of heat was in the firebox and would radiate out at me at what seemed much higher level. I had to turn my face with the door open and a hot bed of coals so much heat was trapped in that firebox. My newer current stove which has a much less insulated fire box has much less heat radiating out at me when I open the door and is much more comfortable to load on hot coals. Lastly I noticed much more coal build up with the more insulated fire box. From the the article I linked in my previous post it states the insulated firebox having a higher build up of heat and the hot coals storing much more heat causes the gases to more quickly out gas out of the wood and leaves much more coals.

I just found a person on another older post saying reloading when the stove is really hot leaves more coals. So this all must be related to high heat and fast out gassing of the wood. Or what it really means is a really hot stove already has alot of hot coals built up in it and your just going to add more hot coals with a new reload of wood. LoL

https://www.hearth.com/talk/threads/coaling-what-causes-it-why-is-it-bad.104356/
https://www.hearth.com/talk/threads/design-deficiency-too-many-coals.29881/
https://www.hearth.com/talk/threads/ack-my-little-stove-is-coaling-up.9883/
https://www.hearth.com/talk/threads/what-is-wrong-with-lots-of-coal.60218/

 

[RSNovi]

I have a Jotul 350. I like my splits smaller around 3 -4" mainly so I can more easily get the wood in there utilizing the most volume of the stove.

 

[Andy S.]

Thanks for the links, Dog. It looks like method of managing coals I've been using (running a few Pine splits between loads of hard wood) is the norm. I'm not seeing anything on the proportionality question and guess I'll just have to test the theory and give the family something else to tease me about. It'll be 80* and humid here today so I've got some time to design the experiment.

 

[aansorge]

...or just get a bigger stove.

 

[BruceNorEast]

Andy,

I've read your post a few times now, and I'm still not sure what your goal is.

You could reduce the frequency of your loads, for example by packing the wood tightly, reducing airflow, and using larger splits.

That will give you longer burns, reducing the "work" of reloading the stove. But that will result in a slower release of heat, and a cooler house.

Smaller splits that have good airflow will release the heat more quickly, requiring more frequent loading, resulting in a warmer house.

 

[Andy S.]

...or just get a bigger stove.

Now you're just being nasty . I would LOVE one of the big boys but was limited by my little prefab fireplace.

I've read your post a few times now, and I'm still not sure what your goal is.

Yeah... I explained myself poorly. Let me try again. Using purchased firewood as a standard, the splits are generally 3-4" and 16" long - one size fits all. Loading what you can fit into a small firebox would be the equivalent of using 6-8" splits or bigger for a large firebox. It seems to me the performance on everything from start-up time to coals management would change. Big boxes have more airflow around the length as well as between the greater number of splits.

My theory is that by reducing the split size proportionally you would mimic the conditions of the big firebox. If a big box is getting 8-10 hours between loads a small guy would be getting 4-5 hours between loads. I doubt too many of us little guys would complain about that. It is more work up front but may be less work in operation. I simply wanted to know if anyone had tried it before I put the work in. That said, I have to confess... I'd end up putting the work in anyway. I'm stubborn that way.

 

[newburner]

If a big box is getting 8-10 hours between loads a small guy would be getting 4-5 hours between loads. I doubt too many of us little guys would complain about that.

No argument here!

 

[velvetfoot]

I agree. Small splits should be better. My previous insert was a 1.7 ft3 quada 2700i. I put 5 cords through that one winter. When it's really cold, you don't have the luxury of time to burn down to ash, and if you really want heat with it, you have to empy out coals along with the ash. Maybe try to let it burn down overnight and empty in the morning.
Upon reflection, I don't think I really contributed anything to this thread.

 

[begreen]

Smaller splits, but not too small are mandatory in a smaller firebox. The big 7-9" splits I can put into the T6 would never have fit in the F3CB. I found that I got the best burns in the F3CB by putting in a couple medium sized splits (4-6") and packing the remaining space with smaller 2-3" splits. If you have a small firebox that loads N/S this is easier. One has to be careful not to pack an E/W loader like the F3CB too much or a log may roll against the glass.

 

[EatenByLimestone]

Throwing a larger round in the back, bottom will allow you a longer burn time, because it reduces the amount of surface area exposed to air to combust. It often has a higher moisture content for the same reasons.

It's a juggling act of sorts as one, big, huge split allows you to fit the most fuel into your stove, but it won't burn. Lots of smaller splits have a large surface area and burn well, but not for a long time.

All I can suggest is to have a bunch of different sizes available and let experience tell you when to break out the all nighters and when to burn the pine and poplar.

 

[etiger2007]

I had a small 1.3 cf. stove at one point, I wonder if i cut some small splits that would fit front to back if that would have helped get a longer burn since you can fit more in a stove N/S. That would mean a lot of work processing the wood. I highly doubt youll ever see long burns with a small stove like that , I never did.

 

[Andy S.]

Thanks for the feedback, everyone. I'm going to play around with it when it gets cold here and see if there is a difference.

 

[velvetfoot]

I just had a brilliant idea. Well maybe not, but still...'

With east to west loading and the concern about splits rolling out, how about using a couple of removable bars, I'm thinking the flat stock at the hardware store, to hold them back. Maybe for overnight, since you'd have to remove them to load.

There are some inserts out there with big capacity but shallow (Clydesdale?).

 

[cookin2night]

The best way I have found to burn with my little box, us stove 2200, is the upside down method. Put as big of pieces as you can on the bottom tightly. Then make a log house oN top of kindling. Then place two fire starter cubes one towards front one towards back inside the log cabin. Make a bunch of newspaper balls and stuff them wherever you can. Light it and watch it last a good 7 to 8 hours. And once the kindling becomes coals you can put big splits on top of that to really heat things up

 

[RSNovi]

Anyone tried those enviro-bricks in a small stove before?

 

[EatenByLimestone]

I tried the compressed wood bricks that tractor supply sells.

They burn if you can keep air under them.

I'd love to say they were awesome and I noticed a huge difference in heat output and burn time, but I didn't. My well seasoned oak performed the same. The bricks claimed something like 8300 btu per lb, which is more than wood, but I didn't notice the difference.

I think they have a place in the world though. I keep a few up at the cabin as it is always dry whereas cordwood may not be.

 

[HotCoals]

I tried the compressed wood bricks that tractor supply sells.

They burn if you can keep air under them.

I'd love to say they were awesome and I noticed a huge difference in heat output and burn time, but I didn't. My well seasoned oak performed the same. The bricks claimed something like 8300 btu per lb, which is more than wood, but I didn't notice the difference.

I think they have a place in the world though. I keep a few up at the cabin as it is always dry whereas cordwood may not be.

Wood is around there also..it's all wood,even pine.

 

[EatenByLimestone]

I thought it was something around 7500.