How long from first light to stable, clean burn in a cold stove?

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Slow1

Minister of Fire
Nov 26, 2008
2,677
Eastern MA
This came up in another thread and I am really curious for different stove models and types how long it takes for folks to get their stoves from cold up to 'ready to walk away.

So some qualifications to try and 'normalize' the results.

Assume that you are starting out with a cold stove - i.e. no coals and fire has been out for a while.
Assume you don't have any draft problems - i.e. let's not include heroic draft starting activities like blowtorches in the flue.
Oh - and speaking of blowtorches, this isn't a question of "how fast can you possibly do it IF you were to employ xyz unusual fire starting method or fuel" rather this is a question of "what is your reasonable normal process get you.

Definition of "done" here is that the stove is in a state that it is burning clean and you consider it good/safe enough to leave unattended for remainder of the burn - i.e. overnight or to leave the house without concern of the stove running away or fire failing to the point that it will start smoking up the neighborhood.

So - I'm sure I've forgotten something here, I hope folks will understand the spirit of the question I'm asking here and will be willing to share their experience in the spirit of exploration and learning that I'm asking. I don't intend this as any sort of competition and I realize there are many variables - there is quite some variation in my own experiences.

Now to be the first to answer :)

This year I have been running from 30-40 minutes from first lighting of the super cedar to the time I have the cat engaged and final air adjustment done on average.

With my first stove (the Encore NC) it would take me closer to 90 minutes before I could be ready to walk away from the stove.

Any other takers?
 
Good question: I'll have to monitor my next cold start - I'm guessing a little over an hour, but I'll find out. I think this is a post - looking forward to seeing what the folks have to say. Cheers!
 
About the same here - newish too!

Shari
 
On the encore cat its typically about 45 minutes to get to the point when the cat is hot enough to light off cleanly. Then close down the air and go so just under an hour.
 
It depends largely on the materials used to line the firebox. Fastest to warmup will be lightweight, highly insulative materials, like pumice or alumina-based refractory firebrick, ceramic fiber board, and a close second, Skamolex (vermiculite). Slowest will be cast iron, steel, and other heavy metals. Generally speaking, the more exposed metal in the firebox, the longer it will take to get it up to operating temperature.
 
precaud said:
It depends largely on the materials used to line the firebox. Fastest to warmup will be lightweight, highly insulative materials, like pumice or alumina-based refractory firebrick, ceramic fiber board, and a close second, Skamolex (vermiculite). Slowest will be cast iron and other heavy metals. Generally speaking, the more exposed metal in the firebox, the longer it will take to get it up to operating temperature.

And how long does it take your stove with your install? Honestly I fully understand there is some really interesting physics involved and that one could in theory design a computer model that answers the question based on whatever variable inputs and constant assumptions you wish to use, but I'm curious about real life experience here across different stoves and different installs. I suspect that there is probably even a marketing answer from manufacturers based on some lab testing - even that isn't of particular interest to me. I find it interesting to hear how long folks are finding with real wood and real installs.

Edit to update - Note also that the question here isn't "how long does it take to get up to temp" - i.e. in my stove I may have everything in what I consider stable (meaning it is burning clean and I can walk away from it safely) yet the stove exterior has not yet hit the peak or even cruising temperature. It takes time for that to happen with the stone so while I may have the air set and cat engaged 40 minutes after light off, the stove may not reach cruising temperature for another hour on the outside of the stove. That is a different question (a good one too, but different).
 
"....but don't be surprised if your answer contains a little more than you were asking for!" :lol:
 
Depends but one of the things I love about a small firebox, lighting the super cedar to clean burn about 15 - 20 minutes, stable (walk away and not worry) about 30 minutes.
 
Slow1, I'm not a round-the-clock burner so most of my fires are cold starts. Both of my stoves have highly insulative fireboxes and warm up quickly. I'd say time to stable burn is maybe 10 minutes at most. The Quad is particularly fast.

One doesn't need a computer model to get a sense of such things. A quick visual inspection of the firebox will tell you a lot without having to get into the nitty-gritty. The more metal you see, the longer it will take.
 
n3pro said:
Depends but one of the things I love about a small firebox, lighting the super cedar to clean burn about 15 - 20 minutes, stable (walk away and not worry) about 30 minutes.
Yep....all oak....I'm not fast enough to use pine
 
Using pine for my starter, I will say an average of 30 minutes. On average. Mostly.
 
precaud said:
Slow1, I'm not a round-the-clock burner so most of my fires are cold starts. Both of my stoves have highly insulative fireboxes and warm up quickly. I'd say time to stable burn is maybe 10 minutes at most. The Quad is particularly fast.

One doesn't need a computer model to get a sense of such things. A quick visual inspection of the firebox will tell you a lot without having to get into the nitty-gritty. The more metal you see, the longer it will take.

Sorry if I came across as testy there - I just could see tangents of arguments about stove materials affecting this or that and the theories behind why and all that overshadowing the actual answers in the thread.

I'm really impressed that you can light up the stove and walk away from it/got to bed 10 minutes later, that is truly impressive. My guess was that 20-30 minutes would be about the shortest times. But that is why I asked the question. I also suspect that there are some very long times out there but somehow I doubt we'll see many of those reported as it is a self-selecting group reporting here and some may not wish to go on record with significantly longer times than they see already listed.
 
Nah, I didn't take it that way, I've gone into the details of that topic in detail in enough posts in the past, no need to rehash it all here.

As others have chimed in, small fireboxes warm up more quickly too. Mine aren't very big. With a top-down startup fire, there's no reason to sit and watch it or tweak it once it's going. I'm in the process of starting one now...
 
if the stove is cold it takes about 45 minutes to burn down some small stuff to get some coals going then i can fill er up and in another 15 minutes cut it back for a long burn. so i would say one hour. pete
 
For me about 45 minutes.
 
30 to 45 minutes to 550º-600º and until Primary Air in final position. It can take a little longer if the kindling fire doesn't roar into action. However, since this stove is still new to us and we're still learning, we keep our eyes on it for another hour or so before leaving.
 
Same for me, mostly because I start the fire now with pretty big splits in the 'tunnel of love™' configuration. It takes a little while for this sized wood to fully ignite. It also depends if it is softwood or hardwood.
 
Depends on what I'm trying to do.

Cold stove to an over night/long burns take 40 mins because I have been starting a large kindling fire to spike temps quick and establish a coal bed, then load the box for a long burn.

If I'm not looking to get optimum burn time I can do a modified top down type fire and that will take 30 min or so with the assistance of 1/5 of a super cedar. But these fires will only last 3 hours or so. Limitations of a small firebox. If I'm home I don't mind it. I generally prefer to do the above mentioned method.
 
And a happy Thanksgiving to all my wood burning afficionados out there. Results from the scenic coast of Maine:

25 minutes to fire up the stone cold Classic in my workroom (which was at 58 °F when I went out this morning). The recipe:

8 newspaper "bowties"
4 pcs. kindling (1" square x 15-16"l) 2 laid diagonally, the other two diagonally placed over the first course.
2 pcs. of bark from splits placed atop the kindling.
Touch it off with by-pass and dampers fully open, door barely cracked. (Enjoy coffee and sunrise)
5 minutes later, add in a couple of larger splits and let the fire get rolling. (The door "jingles" when the fire is ready for more wood)
About 10 minutes later add more splits, close door, and twisty-knob damper. Stove top thermometer is at 250 °F .
Engage catalytic combustor, leaving lower damper open. Listen and watch stovetop thermometer to be sure it's on the rise. I usually give it about 10 minutes to get up to "cruising" speed.
Close lower damper. "Set it and forget it", baby.
 
Takes me about 30min from a cold start to be able to shut the air down and walk away. That's with two splits on either side of the bottom of the stove with a super cedar and kindling in the middle. Smaller splits on top of that.
 
About 4 1/2 hours....... :-S
Truthfully, I don't leave it long or go to bed until things are on the down swing.
One hour after start-up, I can walk away, but I don't go 1/2 hour before coming back for a peak and maybe tweaking.
Still learning. Check with me again in Feb.
 
About 1 hour for my old AShley before engaging the CAT. Then we're off and cruising about 1/2 hr later.
 
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