Kindling Consumption and Startup Procedure

[Quirke]

I understand the rationale behind using dry wood and needing to get these catalytic stoves up to operating temperature before closing the bypass and putting the catalyst to work.

The manual's startup instructions of just using kindling before slowly adding small logs sounds like it will require a lot of kindling and time to restart a cold stove.

In my secondary burn Jotul I found that startup was fastest and easiest with the top-down method, but after some practice with controlling airflow via side door, ashtray, and damper it would start quickly with a full load of normal split pieces and a few big pieces of birch bark.

I know that the King 40 has optimized airflow for operation with the catalyst, but its large firebox seems like it would favour the top-down method, rather than constantly feeding a small kindling fire.

Is there an issue with using top-down that I'm missing? I could see big pieces holding excess moisture that slows down startup, but I'll be burning 2+ year seasoned wood with <15% moisture.

I'm trying to gauge how much kindling I should prepare. The long slow burn times should reduce the number of cold starts I'll need to do, but if a lot is needed each time I want to be prepared. I only used a few buckets worth before relying solely on birch bark so I don't even have much of a reference.

Thank you for your input.

 

[EatenByLimestone]

I consider birch bark as kindling. Kindling is the fastest way to get a stove up to temperature. So, if you stuffed the box full of dry kindling and set it on fire, it’d get hot fast. Most people figure out what works for them through experience. We all have different time lines as to what’s an acceptable amount of time to get warm. Gather as much as you can. If you find it’s too much, stuff it in voids between splits or save it for future years.

 

[Highbeam]

Your need for kindling will be determined by how often you let the stove go cold. The king is the best stove possible to make it through the winter without ever using kindling other than for your first fire of tge season. No other stove has the same burn rate control and fuel tank size.

Personally I go through lots of kindling. I’m not shy about using it to quickly go from just a few coals to an active cat temperature with minimum smoke.

I also do not play that silly game of starting a kindling fire and then loading more wood. It’s a full stove of fuel on top of a kindling pile. Bottom up fires work best for me.

I also make my kindling from my firewood anytime I need it. Just split down full size splits. I don’t save splitter trash or bark fragments.

 

[qwee]

Which is less polluting way to start a fire 1) a top-down fire or 2) a side/bottom fire? Most believe a top-down fire is less polluting. Because the flame is burning the gasses as they are being released and rising. But really the top-down flame isn't hot enough to burn most of these gasses. The most intense part of a flame is above it. The top-down has to burn downward which is the weak part the flame - so it goes slowly and takes time to get very intense.

The bottom/side fires are better. The strongest part of the flame is being utilized hitting wood above it. So overall the fire gets going faster. The key is to get the fire hot as quickly as possible. So, lots of kindling would be a good thing. Highest levels of pollutants occurs at start up. It is counterintuitive but side and bottom fires are less polluting than top-down fires because they get this chemical reaction (the fire) to its max more quickly. And max is where the least pollution occurs.

 

[Quirke]

I also do not play that silly game of starting a kindling fire and then loading more wood. It’s a full stove of fuel on top of a kindling pile. Bottom up fires work best for me.

Wonderful. That was what I was hoping would be the case.

Most of my splits are on the smaller size for quick restarting from coals and easier packing into the smaller oddly shaped Jotul firebox, so building a warm stove back up from coals should be easy without kindling.

I've got a few cords of big all-nighters that would just fit in the Jotul, but I'm not sure that they'll be especially useful in the King since it sounds like the thermostat does most of the work controlling the burn rate.

I also make my kindling from my firewood anytime I need it. Just split down full size splits. I don’t save splitter trash or bark fragments.

I haven't harvested any softwood for splitting into ideal kindling since the birch bark had been sufficient and I'm trying to build up my supply of hardwood. I know split hardwood kindling is better than nothing, but the manual spooked me into thinking I'll want a cord of ideal softwood kindling. I have a decent supply of lumber cut-offs that should be plenty for a winter.

I'm excited to see how this stove performs.

 

[Dieselhead]

I load the box to the gills on a cold start and then put a small pile of kindling in front and that lights the main event. Never build up to a larger fire from kindling. Having seasoned wood makes this method work well.

The next days load is started from the previous days coals.

 

[Quirke]

Which is less polluting way to start a fire 1) a top-down fire or 2) a side/bottom fire? Most believe a top-down fire is less polluting. Because the flame is burning the gasses as they are being released and rising. But really the top-down flame isn't hot enough to burn most of these gasses. The most intense part of a flame is above it. The top-down has to burn downward which is the weak part the flame - so it goes slowly and takes time to get very intense.

The bottom/side fires are better. The strongest part of the flame is being utilized hitting wood above it. So overall the fire gets going faster. The key is to get the fire hot as quickly as possible. So, lots of kindling would be a good thing. Highest levels of pollutants occurs at start up. It is counterintuitive but side and bottom fires are less polluting than top-down fires because they get this chemical reaction (the fire) to its max more quickly. And max is where the least pollution occurs.

I don't disagree with you, in fact I agree, but what initially drew me to the top down fire is the ease of setup and not having to worry about poor airflow that can smother the fire.

In the Jotul I could build a top down 3x as fast, light it, close the doors, open the damper fully, and go about my morning routine while it reliably started up.
In switching to a bottom up with birch bark for kindling, I was indeed able to more quickly start up the fire, but it required a few more minutes of selecting the ideal pieces of wood, positioning them, and then manually manipulating the side door and ashtray door to optimally feed air to the flames. While the side door allows for some interesting airflow manipulation, it is terrible for loading and the keyed double front doors of the stove are only good for cleaning access. I will not miss the hassle of the Jotul design.

My thinking for why the top-down would be good in a King is that it would be easy to position the flame directly below the by-pass, feeding the hot gasses up the chimney to ensure smoke doesn't enter the house, and to quickly establish a draft to feed more air. The BK design doesn't have air channels at the bottom of the firebox which optimally feed a bottom up fire the way secondary burns are designed.

But that's just my guess and I appreciate learning from others' experience to save me from guesswork and mistakes. 😀

 

[Highbeam]

I've got a few cords of big all-nighters that would just fit in the Jotul, but I'm not sure that they'll be especially useful in the King since it sounds like the thermostat does most of the work controlling the burn rate.



I haven't harvested any softwood for splitting into ideal kindling since the birch bark had been sufficient and I'm trying to build up my supply of hardwood. I know split hardwood kindling is better than nothing, but the manual spooked me into thinking I'll want a cord of ideal softwood kindling. I have a decent supply of lumber cut-offs that should be plenty for a winter.

I'm excited to see how this stove performs

BK recommends larger splits to help with a long and low burn. Too small and not even the thermostat can keep the burn rate down. You'll learn what you like from experience. I have found that the medium sized splits (or a mix) allow me to fill the princess firebox more full than just large splits. You can't lose, and dry wood is more important than perfect split size.

I split hardwood or softwood kindling. Currently it's all maple kindling. It all works great once dry but I do admit that the softwoods split easier into perfect little kindling sticks. I light the kindling with a hand held, trigger operated, propane torch. Clean and fast. Smoke rollout is not a problem for me during cold starts. It rolls out a lot during warm or hot reloads while there is still fuel burning. Just a quirk of this stove with the bypass opening being so low in relation to the loading door.

My thinking for why the top-down would be good in a King is that it would be easy to position the flame directly below the by-pass, feeding the hot gasses up the chimney to ensure smoke doesn't enter the house, and to quickly establish a draft to feed more air. The BK design doesn't have air channels at the bottom of the firebox which optimally feed a bottom up fire the way secondary burns are designed.

But that's just my guess and I appreciate learning from others' experience to save me from guesswork and mistakes. 😀

One problem you can have with a bypass opening right above the fire is that you can overtemp the flue really fast. This is also a way to maybe melt those fragile bypass gasket retainers. I am not a fan of getting that bypass opening hot. It's all cold steel, this stove design is a smoker until the cat is very active. Noncats use an insulated firebox roof and are much cleaner at startup.

I currently burn both a noncat and a cat stove and the noncat is much cleaner. I can count on visible smoke for much longer from the BK.

 

[Quirke]

BK recommends larger splits to help with a long and low burn. Too small and not even the thermostat can keep the burn rate down.

Noted.

One problem you can have with a bypass opening right above the fire is that you can overtemp the flue really fast. This is also a way to maybe melt those fragile bypass gasket retainers.

Also noted.

Great tips, thank you.

 

[Tron]

I just stuff the firebox full of splits and light a firestarter somewhere in the middle of it. Raging flames within a few minutes and the cat is at temperature shortly after that, maybe 15min after light-off.
As others have said, dry splits is what the stove is designed for and what makes that method work well.

 

[bigealta]

Which is less polluting way to start a fire 1) a top-down fire or 2) a side/bottom fire? Most believe a top-down fire is less polluting. Because the flame is burning the gasses as they are being released and rising. But really the top-down flame isn't hot enough to burn most of these gasses. The most intense part of a flame is above it. The top-down has to burn downward which is the weak part the flame - so it goes slowly and takes time to get very intense.

The bottom/side fires are better. The strongest part of the flame is being utilized hitting wood above it. So overall the fire gets going faster. The key is to get the fire hot as quickly as possible. So, lots of kindling would be a good thing. Highest levels of pollutants occurs at start up. It is counterintuitive but side and bottom fires are less polluting than top-down fires because they get this chemical reaction (the fire) to its max more quickly. And max is where the least pollution occurs.

Not true in my jotul secondary stove. Top down is Much cleaner than bottom up. Why? Because the secondaries light up within minutes.

And if you are "cheating" by using the ash pan door to get a bottom up starting faster, be prepaired to buy a new stove when you crack the cast iron.