Top-down Burn not the Best?

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Yes but those tubes aren't going to be activated until the fire gets going. The small top down fire probably isn't going to bring these tubes into play - the bottom fire is more likely to get these tubes up and going because it gets the fire going faster.
I get much better results on a cold start full load with top down, but I have a pretty big box. It takes a while to get to cruising, but it's making heat and warming everything up pretty quick.

Cold start smaller fire to just take the chill out or heat the stove and flue up a bottom start works better for me.
 
My stoves do not do well with top down lights. In fact one of them only starts properly when loading splits onto a kindling fire right under the baffle opening.
 
Yes but those tubes aren't going to be activated until the fire gets going. The small top down fire probably isn't going to bring these tubes into play - the bottom fire is more likely to get these tubes up and going because it gets the fire going faster.
Respectfully disagree. The tubes heat right up from whatever small stuff I use to light the fire, and are burning smoke through the whole start up process. I also get way more smoke loading on top of a bed of hot coals than I get from a cold top down start.

Listen, I start from the bottom, middle, top, left, right, or wherever the best spot is for the particular load. I try to add an easy lighting piece like tulip poplar close to the spot where I light. If I start from the top, the tubes heat up and start burning smoke. If I start from the bottom, the top pieces insulate the tubes, and it billows smoke until most of the stove is blazing. There's usually about 15 minutes difference.

I'm not going by a stove without tubes at the top, and I give no credence to a study done on stoves in 1993 before the modern regs changed the stoves. Your experience may vary, and your stove is certainly different.

My vote is strongly for top down starts being much cleaner than bottom up starts on stoves with secondary tubes.
 
I wonder if there is a difference for a cat stove compared to a secondary stove. What about hybrids?
 
Finally, maybe I have figured out the best way to start a fire in an empty firebox. By best way, I mean the way that will reduce the amount of pollution the wood burning appliance creates on start-up. I'm unsure if this product has been created yet. Let's make up a name for it ----how about a flamethrower.

What is a flamethrower? It is like fireworks. It throws out big flames for a minute or two. It requires the burner to surround the flamethrower with small kindling/paper such that a big fire will start almost immediately. I think there are already things like this. But I want it bigger then those little survival ones. And it should throw out something very flammable when it explodes that sticks to wood and burns. Gunpowder? Solid diesel/gas fuel? I don't know.

Now, this could be a fad that actually has positive benefits. In no time, boom, you have a fire going. And it would be fun setting it off, too. Ok, who wants to build the prototype?
 
My biggest problem with a top down is that I have a strong draft and have to be careful of new wood out gassing in a hot stove. With top down the secondaries could get roaring before the bottom splits are even charred. Once they catch fire it could go nuclear.

The front method for me lets everything burn a little to avoid that. Also, with lighting the front I still get a fire on top of the splits somewhat quickly. I usually with put a few pieces of kindling east west on top near the front of the baffle. The smoke escapes near the door and these give a final burn before moving up into the passage to the flue. Maybe that’s a top down fire lit from the bottom...
 
I load E/W and lit from top back. Then I put a good split in the front so it's top edge is about 1'' away from the front tube. The draft will pull the flame from the kindling to "lick" the final piece of wood and get secondary going. If I put kindling in front the pile of kindling will burn and crumble and slide down to my glass. With a "gate keeper" in there, I can hold the pile of wood in better form for much longer.
 
Here's a video of my bottom-up method. In this video it's 40 seconds from lighting to flames at the secondary tubes. I can't come anywhere close to this with a top-down method.

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I wonder if there is a difference for a cat stove compared to a secondary stove. What about hybrids?
We all do what works for us. Every one has success with different methods. I prefer top/down. I put some small stuff on top more to the front and under the cat. The cat gets to temp quick, less smoke and once the cat is at temp and fire is going well, the bypass is shut. I shoot for bringing the cat to temp as quickly as possible. It works for me.
 
Here's a video of my bottom-up method. In this video it's 40 seconds from lighting to flames at the secondary tubes. I can't come anywhere close to this with a top-down method.

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That's some good technique there. Much better than the way I do it. Appreciate the video, and I'd say best in class for keeping emissions low.

Only downside is it's labor intensive, but I also appreciate that you're making the effort. I'd wager that you also burn good dry wood. Your the kind of person we'd all welcome as a wood heating neighbor.
 
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Yes, thanks for the video. That starting method gets your fire going quickly. I'm going to need to bookmark that - I've never seen someone get a fire going that fast.
 
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That's some good technique there. Much better than the way I do it. Appreciate the video, and I'd say best in class for keeping emissions low.

Only downside is it's labor intensive, but I also appreciate that you're making the effort. I'd wager that you also burn good dry wood. Your the kind of person we'd all welcome as a wood heating neighbor.

Thank you. It does take a couple minutes to put together, but I've done it enough now that it's quite quick. We do have very dry wood, we have a lot of dry standing spruce and pine around, it's uncommon for me to find one >20% moisture content.

I really like the softwood pellets for lighting, it provides a substantial amount of heat to get things going. I actually stumbled across it by accident, I wound up with a bag that I needed to get rid of, this is what I came up with.
 
Here's a video of my bottom-up method. In this video it's 40 seconds from lighting to flames at the secondary tubes. I can't come anywhere close to this with a top-down method.

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This is a good way to get it started hot and fast. Anything with the cross cross method will pretty well. Actually, I think this a third option. It’s more a “build a small fire first” method. I’ve thought about doing that but I always end up just doing a full load. I think the most debate is around a full load with a cold stove.
 
I something very similar with my wood cookstove, but I split down my small knot free splits or construction waste down to pencil sized and build a little "log cabin" and light that up with a large butane torch. Once that has been burning for a minute or two I can throw my splits on top and have a raging fire in just a few minutes.
 
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This is a good way to get it started hot and fast. Anything with the cross cross method will pretty well. Actually, I think this a third option. It’s more a “build a small fire first” method. I’ve thought about doing that but I always end up just doing a full load. I think the most debate is around a full load with a cold stove.

I guess I've never had a reason to light with a full load, I have placed another row on top, or used bigger splits to get a fuller load. But with my schedule I come home from work, light a fire like this, and then fill the stove on the coals for an overnight burn. Trying to light a full load after work would mean far to many coals at bedtime.
 
I guess I've never had a reason to light with a full load, I have placed another row on top, or used bigger splits to get a fuller load. But with my schedule I come home from work, light a fire like this, and then fill the stove on the coals for an overnight burn. Trying to light a full load after work would mean far to many coals at bedtime.

Same here. If I light a full load after getting home from work it really screws up my routine.

I do full load cold starts all the time though with bottom start. I have no need for a warm up load for my stove. Load it full if routine permits,bottom start, and the stove takes care of the rest.
 
This is a Masonry Heater study in Austria. I wonder if it is the same for wood stoves?

Ah... (as has been said) There's the rub.

First, I am a top down burner. Almost religiously (to me, if one has problems with a top down, then my first opinion is they are probably doing it wrong... one can be blinded by religion... ;)).

But back to masonry heaters..... Masonry heaters are a different animal. Most I have used have a long burn chamber designed specifically for front to back burns. And not *just* front to back but front *bottom* to back. Even starting a fire in the front, but at the top, is not ideal.

The closest free standing stove I have used that is like a masonry heater was a Jotul 118 I used for years (purchased thirty years ago, so the old original designed one from the 1930's, so not the new "clean burning" one.... ). Definitely a front to back burner. Top down was a no go. But a similar process of loading (simply in the horizontal rather than the vertical). So on starting, large logs stuffed into the back, and progressively smaller and smaller ones placed toward the front. The high surface area of the smaller front wood starts a very hot fire, very quickly, which then easily combusts the larger logs in the back** without needing to "crack" open the door or even revisit the stove for quite a while during startup -- some of the same very desirable characteristics I appreciate about a top down burn as well,

Also to consider: First, not all parts of a stove are created equal. Slower startups allow all those different components to acclimate to rising temps gradually, reducing stress between components. Possible extending the live of the the stove. Second, my stoves are currently both convection stoves. So slower startups (in about an hour the integrated oven thermometer shows about 250°C (480°F), which means the stove and exhaust pipes are already hotter sooner) are fine for me because they will still take time to "heat" the room regardless of how fast the fire starts. So to get really, really fast startups are rather pointless for me, because of how my stoves heat the house. But once they heat, the heat really well. The entire air in the house is warm. Needing no overnight burns.

** And once things were really cooking, rake forward the coals, and I would stuff in really long splits. Would burn all day. Front to back. Turn the house into a sauna if I let it. Great stove. Miss it. I moved. To heavy to transport across the Atlantic.
 
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