What is the benefit if 1” ash layer in continuous burn?

[Sean in the woods]

I read and heard from several sources, including my wood stove manual, that I should leave at least 1” of ash on the floor of the firebox at all times.
Why?

More to the point, If I am doing continuous burns and the floor of the firebox never gets cold do I need to leave a blanket of ash? What is the actual benefit? I was thinking that not having the ash under the first layer of a new load of wood in a warm stove would be better because it would allow air circulation underneath the wood and aid the start.

What say you?

 

[Gearhead660]

The ash acts as insulation. Keeps fire/coals hot longer.

 

[Osage]

The ash acts as insulation. Keeps fire/coals hot longer.

The Native Americans used to carry a hot coal in a skin bag surrounded by ash when moving camps. The insulation of ash kept the coal going longer than when exposed to air.

 

[Sean in the woods]

The ash acts as insulation. Keeps fire/coals hot longer.

I understand that.

However, at the point when I am starting a new load on the coals of yesterday’s burn, the ash is not needed to insulate anymore is it? If so, why?

If the ash is no longer needed, does it benefit or hinder the new fire as it catches and grows?

 

[BigJ273]

Insulation

 

[Ctwoodtick]

Insulation

 

[SpaceBus]

Leave the ash, it keeps more heat in the firebox.

 

[Bad LP]

I recall some stoves that wanted a layer of sand in the bottom.

 

[SpaceBus]

I recall some stoves that wanted a layer of sand in the bottom.

I think this is how the first owner of our house killed the Defiant I that came with the house.

 

[Bad LP]

My insert burns better with a couple of fires worth of ash on the bottom. Remarkably better.

 

[brenndatomu]

You can always try it with and without ash...see what you think...

 

[SpaceBus]

Agreed, my stove also burns best with a good layer of ash.

 

[Sean in the woods]

Agreed, my stove also burns best with a good layer of ash.

You can always try it with and without ash...see what you think...

As a noob burner, everything I do lately is an experiment. I’ll try both ways & see how it goes in my stove/wood/weather conditions.

 

[agonyzhou]

It is the other way arond: For continuous burn you need some ash to preserve the coal. Otherwise if you reload late and there is no coal.
For cold start you do not need the ash.

 

[Sean in the woods]

It is the other way arond: For continuous burn you need some ash to preserve the coal. Otherwise if you reload late and there is no coal.
For cold start you do not need the ash.

I just realized that I didn’t include something in my original question.

I just ordered a tool to easily separate the hot coals from the ash. My thought is that in the morning with a warm stove and a mix of ash and hot coals, I’ll remove the ash leaving just the hot coals. My thinking is that the stove is already warm so insulation is not needed as much. Also without the ash, there will be more air flow around the coals and the bottom of the wood that I want them to light.

 

[Mutineer]

I have been using a slotted stove shovel for several years to do exactly what Sean is saying- I sift out the coals, hot or not, from the ash and keep the burn going with fresh splits on top of the pile of coals. Being on the anal side, I like to get the max out of the wood and having coals buried in the ash layer and not igniting defeats that aim. Burning straight red oak (my ideal mission) defeats this somewhat as the oak leaves negligible ash or coals, and I build up clinkers in the bottom after a couple of weeks of steady burn.

 

[agonyzhou]

I just realized that I didn’t include something in my original question.

I just ordered a tool to easily separate the hot coals from the ash. My thought is that in the morning with a warm stove and a mix of ash and hot coals, I’ll remove the ash leaving just the hot coals. My thinking is that the stove is already warm so insulation is not needed as much. Also without the ash, there will be more air flow around the coals and the bottom of the wood that I want them to light.

I don't think there will be a difference. For a warm reload you need: enough hot coal, good contact from the coal to wood, and a small gap between the wood for the initial flame to rise up quickly. How much ash underneath should not matter much.

 

[brenndatomu]

Just using a small rake will pull the coals up out of the ashes...I made one from an old garden rake...cut it down width wise, welded a piece of rebar on for a handle, BBQ paint, done...works well.

 

[Gearhead660]

Usually leave a layer of ash as I burn 24/7. On reload, push the ash back, rake out the coals, put them in front and spread out ash evenly. every few days I remove some of the ash.

 

[begreen]

I understand that.

However, at the point when I am starting a new load on the coals of yesterday’s burn, the ash is not needed to insulate anymore is it? If so, why?

If the ash is no longer needed, does it benefit or hinder the new fire as it catches and grows?

Insulating the firebox lets the fire get hotter quicker. Doing so leads to cleaner burning. The sooner the firebox gets hot enough for secondary combustion the better.

 

[SpaceBus]

Insulating the firebox lets the fire get hotter quicker. Doing so leads to cleaner burning. The sooner the firebox gets hot enough for secondary combustion the better.

Indeed, I find my stoves are much slower to get up to temperature when emptied of ash.

 

[xman23]

Defiantly does work better with a bed of ash. But when I clean the stove I clean it all out.

 

[begreen]

Defiantly does work better with a bed of ash. But when I clean the stove I clean it all out.

Depends on the stove. Some, like the Jotul F602, recommend leaving a 1" ash bed after cleaning. In lieu of that, before the first fire it is recommended to lay down a bed of clean sand.

 

[Sean in the woods]

Interesting. Thanks again all for sharing your experience. Saves me time.

BTW, this is the tool I’ll be playing with once it comes in:

 

[BigJ273]

Interesting. Thanks again all for sharing your experience. Saves me time.

BTW, this is the tool I’ll be playing with once it comes in:

Do u have a link?